Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging
[qemu/ar7.git] / qga / commands.c
blob58568d845230f9cf7ec69d1f3e76fa39eb712e32
1 /*
2 * QEMU Guest Agent common/cross-platform command implementations
4 * Copyright IBM Corp. 2012
6 * Authors:
7 * Michael Roth <mdroth@linux.vnet.ibm.com>
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.
13 #include <glib.h>
14 #include "qga/guest-agent-core.h"
15 #include "qga-qmp-commands.h"
16 #include "qapi/qmp/qerror.h"
17 #include "qemu/base64.h"
19 /* Maximum captured guest-exec out_data/err_data - 16MB */
20 #define GUEST_EXEC_MAX_OUTPUT (16*1024*1024)
21 /* Allocation and I/O buffer for reading guest-exec out_data/err_data - 4KB */
22 #define GUEST_EXEC_IO_SIZE (4*1024)
24 /* Note: in some situations, like with the fsfreeze, logging may be
25 * temporarilly disabled. if it is necessary that a command be able
26 * to log for accounting purposes, check ga_logging_enabled() beforehand,
27 * and use the QERR_QGA_LOGGING_DISABLED to generate an error
29 void slog(const gchar *fmt, ...)
31 va_list ap;
33 va_start(ap, fmt);
34 g_logv("syslog", G_LOG_LEVEL_INFO, fmt, ap);
35 va_end(ap);
38 int64_t qmp_guest_sync_delimited(int64_t id, Error **errp)
40 ga_set_response_delimited(ga_state);
41 return id;
44 int64_t qmp_guest_sync(int64_t id, Error **errp)
46 return id;
49 void qmp_guest_ping(Error **errp)
51 slog("guest-ping called");
54 static void qmp_command_info(QmpCommand *cmd, void *opaque)
56 GuestAgentInfo *info = opaque;
57 GuestAgentCommandInfo *cmd_info;
58 GuestAgentCommandInfoList *cmd_info_list;
60 cmd_info = g_new0(GuestAgentCommandInfo, 1);
61 cmd_info->name = g_strdup(qmp_command_name(cmd));
62 cmd_info->enabled = qmp_command_is_enabled(cmd);
63 cmd_info->success_response = qmp_has_success_response(cmd);
65 cmd_info_list = g_new0(GuestAgentCommandInfoList, 1);
66 cmd_info_list->value = cmd_info;
67 cmd_info_list->next = info->supported_commands;
68 info->supported_commands = cmd_info_list;
71 struct GuestAgentInfo *qmp_guest_info(Error **errp)
73 GuestAgentInfo *info = g_new0(GuestAgentInfo, 1);
75 info->version = g_strdup(QEMU_VERSION);
76 qmp_for_each_command(qmp_command_info, info);
77 return info;
80 struct GuestExecIOData {
81 guchar *data;
82 gsize size;
83 gsize length;
84 gint closed;
85 bool truncated;
86 const char *name;
88 typedef struct GuestExecIOData GuestExecIOData;
90 struct GuestExecInfo {
91 GPid pid;
92 int64_t pid_numeric;
93 gint status;
94 bool has_output;
95 gint finished;
96 GuestExecIOData in;
97 GuestExecIOData out;
98 GuestExecIOData err;
99 QTAILQ_ENTRY(GuestExecInfo) next;
101 typedef struct GuestExecInfo GuestExecInfo;
103 static struct {
104 QTAILQ_HEAD(, GuestExecInfo) processes;
105 } guest_exec_state = {
106 .processes = QTAILQ_HEAD_INITIALIZER(guest_exec_state.processes),
109 static int64_t gpid_to_int64(GPid pid)
111 #ifdef G_OS_WIN32
112 return GetProcessId(pid);
113 #else
114 return (int64_t)pid;
115 #endif
118 static GuestExecInfo *guest_exec_info_add(GPid pid)
120 GuestExecInfo *gei;
122 gei = g_new0(GuestExecInfo, 1);
123 gei->pid = pid;
124 gei->pid_numeric = gpid_to_int64(pid);
125 QTAILQ_INSERT_TAIL(&guest_exec_state.processes, gei, next);
127 return gei;
130 static GuestExecInfo *guest_exec_info_find(int64_t pid_numeric)
132 GuestExecInfo *gei;
134 QTAILQ_FOREACH(gei, &guest_exec_state.processes, next) {
135 if (gei->pid_numeric == pid_numeric) {
136 return gei;
140 return NULL;
143 GuestExecStatus *qmp_guest_exec_status(int64_t pid, Error **err)
145 GuestExecInfo *gei;
146 GuestExecStatus *ges;
148 slog("guest-exec-status called, pid: %u", (uint32_t)pid);
150 gei = guest_exec_info_find(pid);
151 if (gei == NULL) {
152 error_setg(err, QERR_INVALID_PARAMETER, "pid");
153 return NULL;
156 ges = g_new0(GuestExecStatus, 1);
158 bool finished = g_atomic_int_get(&gei->finished);
160 /* need to wait till output channels are closed
161 * to be sure we captured all output at this point */
162 if (gei->has_output) {
163 finished = finished && g_atomic_int_get(&gei->out.closed);
164 finished = finished && g_atomic_int_get(&gei->err.closed);
167 ges->exited = finished;
168 if (finished) {
169 /* Glib has no portable way to parse exit status.
170 * On UNIX, we can get either exit code from normal termination
171 * or signal number.
172 * On Windows, it is either the same exit code or the exception
173 * value for an unhandled exception that caused the process
174 * to terminate.
175 * See MSDN for GetExitCodeProcess() and ntstatus.h for possible
176 * well-known codes, e.g. C0000005 ACCESS_DENIED - analog of SIGSEGV
177 * References:
178 * https://msdn.microsoft.com/en-us/library/windows/desktop/ms683189(v=vs.85).aspx
179 * https://msdn.microsoft.com/en-us/library/aa260331(v=vs.60).aspx
181 #ifdef G_OS_WIN32
182 /* Additionally WIN32 does not provide any additional information
183 * on whetherthe child exited or terminated via signal.
184 * We use this simple range check to distingish application exit code
185 * (usually value less then 256) and unhandled exception code with
186 * ntstatus (always value greater then 0xC0000005). */
187 if ((uint32_t)gei->status < 0xC0000000U) {
188 ges->has_exitcode = true;
189 ges->exitcode = gei->status;
190 } else {
191 ges->has_signal = true;
192 ges->signal = gei->status;
194 #else
195 if (WIFEXITED(gei->status)) {
196 ges->has_exitcode = true;
197 ges->exitcode = WEXITSTATUS(gei->status);
198 } else if (WIFSIGNALED(gei->status)) {
199 ges->has_signal = true;
200 ges->signal = WTERMSIG(gei->status);
202 #endif
203 if (gei->out.length > 0) {
204 ges->has_out_data = true;
205 ges->out_data = g_base64_encode(gei->out.data, gei->out.length);
206 g_free(gei->out.data);
207 ges->has_out_truncated = gei->out.truncated;
210 if (gei->err.length > 0) {
211 ges->has_err_data = true;
212 ges->err_data = g_base64_encode(gei->err.data, gei->err.length);
213 g_free(gei->err.data);
214 ges->has_err_truncated = gei->err.truncated;
217 QTAILQ_REMOVE(&guest_exec_state.processes, gei, next);
218 g_free(gei);
221 return ges;
224 /* Get environment variables or arguments array for execve(). */
225 static char **guest_exec_get_args(const strList *entry, bool log)
227 const strList *it;
228 int count = 1, i = 0; /* reserve for NULL terminator */
229 char **args;
230 char *str; /* for logging array of arguments */
231 size_t str_size = 1;
233 for (it = entry; it != NULL; it = it->next) {
234 count++;
235 str_size += 1 + strlen(it->value);
238 str = g_malloc(str_size);
239 *str = 0;
240 args = g_malloc(count * sizeof(char *));
241 for (it = entry; it != NULL; it = it->next) {
242 args[i++] = it->value;
243 pstrcat(str, str_size, it->value);
244 if (it->next) {
245 pstrcat(str, str_size, " ");
248 args[i] = NULL;
250 if (log) {
251 slog("guest-exec called: \"%s\"", str);
253 g_free(str);
255 return args;
258 static void guest_exec_child_watch(GPid pid, gint status, gpointer data)
260 GuestExecInfo *gei = (GuestExecInfo *)data;
262 g_debug("guest_exec_child_watch called, pid: %d, status: %u",
263 (int32_t)gpid_to_int64(pid), (uint32_t)status);
265 gei->status = status;
266 gei->finished = true;
268 g_spawn_close_pid(pid);
271 /** Reset ignored signals back to default. */
272 static void guest_exec_task_setup(gpointer data)
274 #if !defined(G_OS_WIN32)
275 struct sigaction sigact;
277 memset(&sigact, 0, sizeof(struct sigaction));
278 sigact.sa_handler = SIG_DFL;
280 if (sigaction(SIGPIPE, &sigact, NULL) != 0) {
281 slog("sigaction() failed to reset child process's SIGPIPE: %s",
282 strerror(errno));
284 #endif
287 static gboolean guest_exec_input_watch(GIOChannel *ch,
288 GIOCondition cond, gpointer p_)
290 GuestExecIOData *p = (GuestExecIOData *)p_;
291 gsize bytes_written = 0;
292 GIOStatus status;
293 GError *gerr = NULL;
295 /* nothing left to write */
296 if (p->size == p->length) {
297 goto done;
300 status = g_io_channel_write_chars(ch, (gchar *)p->data + p->length,
301 p->size - p->length, &bytes_written, &gerr);
303 /* can be not 0 even if not G_IO_STATUS_NORMAL */
304 if (bytes_written != 0) {
305 p->length += bytes_written;
308 /* continue write, our callback will be called again */
309 if (status == G_IO_STATUS_NORMAL || status == G_IO_STATUS_AGAIN) {
310 return true;
313 if (gerr) {
314 g_warning("qga: i/o error writing to input_data channel: %s",
315 gerr->message);
316 g_error_free(gerr);
319 done:
320 g_io_channel_shutdown(ch, true, NULL);
321 g_io_channel_unref(ch);
322 g_atomic_int_set(&p->closed, 1);
323 g_free(p->data);
325 return false;
328 static gboolean guest_exec_output_watch(GIOChannel *ch,
329 GIOCondition cond, gpointer p_)
331 GuestExecIOData *p = (GuestExecIOData *)p_;
332 gsize bytes_read;
333 GIOStatus gstatus;
335 if (cond == G_IO_HUP || cond == G_IO_ERR) {
336 goto close;
339 if (p->size == p->length) {
340 gpointer t = NULL;
341 if (!p->truncated && p->size < GUEST_EXEC_MAX_OUTPUT) {
342 t = g_try_realloc(p->data, p->size + GUEST_EXEC_IO_SIZE);
344 if (t == NULL) {
345 /* ignore truncated output */
346 gchar buf[GUEST_EXEC_IO_SIZE];
348 p->truncated = true;
349 gstatus = g_io_channel_read_chars(ch, buf, sizeof(buf),
350 &bytes_read, NULL);
351 if (gstatus == G_IO_STATUS_EOF || gstatus == G_IO_STATUS_ERROR) {
352 goto close;
355 return true;
357 p->size += GUEST_EXEC_IO_SIZE;
358 p->data = t;
361 /* Calling read API once.
362 * On next available data our callback will be called again */
363 gstatus = g_io_channel_read_chars(ch, (gchar *)p->data + p->length,
364 p->size - p->length, &bytes_read, NULL);
365 if (gstatus == G_IO_STATUS_EOF || gstatus == G_IO_STATUS_ERROR) {
366 goto close;
369 p->length += bytes_read;
371 return true;
373 close:
374 g_io_channel_unref(ch);
375 g_atomic_int_set(&p->closed, 1);
376 return false;
379 GuestExec *qmp_guest_exec(const char *path,
380 bool has_arg, strList *arg,
381 bool has_env, strList *env,
382 bool has_input_data, const char *input_data,
383 bool has_capture_output, bool capture_output,
384 Error **err)
386 GPid pid;
387 GuestExec *ge = NULL;
388 GuestExecInfo *gei;
389 char **argv, **envp;
390 strList arglist;
391 gboolean ret;
392 GError *gerr = NULL;
393 gint in_fd, out_fd, err_fd;
394 GIOChannel *in_ch, *out_ch, *err_ch;
395 GSpawnFlags flags;
396 bool has_output = (has_capture_output && capture_output);
397 uint8_t *input = NULL;
398 size_t ninput = 0;
400 arglist.value = (char *)path;
401 arglist.next = has_arg ? arg : NULL;
403 if (has_input_data) {
404 input = qbase64_decode(input_data, -1, &ninput, err);
405 if (!input) {
406 return NULL;
410 argv = guest_exec_get_args(&arglist, true);
411 envp = has_env ? guest_exec_get_args(env, false) : NULL;
413 flags = G_SPAWN_SEARCH_PATH | G_SPAWN_DO_NOT_REAP_CHILD;
414 #if GLIB_CHECK_VERSION(2, 33, 2)
415 flags |= G_SPAWN_SEARCH_PATH_FROM_ENVP;
416 #endif
417 if (!has_output) {
418 flags |= G_SPAWN_STDOUT_TO_DEV_NULL | G_SPAWN_STDERR_TO_DEV_NULL;
421 ret = g_spawn_async_with_pipes(NULL, argv, envp, flags,
422 guest_exec_task_setup, NULL, &pid, has_input_data ? &in_fd : NULL,
423 has_output ? &out_fd : NULL, has_output ? &err_fd : NULL, &gerr);
424 if (!ret) {
425 error_setg(err, QERR_QGA_COMMAND_FAILED, gerr->message);
426 g_error_free(gerr);
427 goto done;
430 ge = g_new0(GuestExec, 1);
431 ge->pid = gpid_to_int64(pid);
433 gei = guest_exec_info_add(pid);
434 gei->has_output = has_output;
435 g_child_watch_add(pid, guest_exec_child_watch, gei);
437 if (has_input_data) {
438 gei->in.data = input;
439 gei->in.size = ninput;
440 #ifdef G_OS_WIN32
441 in_ch = g_io_channel_win32_new_fd(in_fd);
442 #else
443 in_ch = g_io_channel_unix_new(in_fd);
444 #endif
445 g_io_channel_set_encoding(in_ch, NULL, NULL);
446 g_io_channel_set_buffered(in_ch, false);
447 g_io_channel_set_flags(in_ch, G_IO_FLAG_NONBLOCK, NULL);
448 g_io_add_watch(in_ch, G_IO_OUT, guest_exec_input_watch, &gei->in);
451 if (has_output) {
452 #ifdef G_OS_WIN32
453 out_ch = g_io_channel_win32_new_fd(out_fd);
454 err_ch = g_io_channel_win32_new_fd(err_fd);
455 #else
456 out_ch = g_io_channel_unix_new(out_fd);
457 err_ch = g_io_channel_unix_new(err_fd);
458 #endif
459 g_io_channel_set_encoding(out_ch, NULL, NULL);
460 g_io_channel_set_encoding(err_ch, NULL, NULL);
461 g_io_channel_set_buffered(out_ch, false);
462 g_io_channel_set_buffered(err_ch, false);
463 g_io_add_watch(out_ch, G_IO_IN | G_IO_HUP,
464 guest_exec_output_watch, &gei->out);
465 g_io_add_watch(err_ch, G_IO_IN | G_IO_HUP,
466 guest_exec_output_watch, &gei->err);
469 done:
470 g_free(argv);
471 g_free(envp);
473 return ge;