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-rw-r--r--src/qga/commands.c463
1 files changed, 463 insertions, 0 deletions
diff --git a/src/qga/commands.c b/src/qga/commands.c
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--- /dev/null
+++ b/src/qga/commands.c
@@ -0,0 +1,463 @@
+/*
+ * QEMU Guest Agent common/cross-platform command implementations
+ *
+ * Copyright IBM Corp. 2012
+ *
+ * Authors:
+ * Michael Roth <mdroth@linux.vnet.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include <glib.h>
+#include "qga/guest-agent-core.h"
+#include "qga-qmp-commands.h"
+#include "qapi/qmp/qerror.h"
+
+/* Maximum captured guest-exec out_data/err_data - 16MB */
+#define GUEST_EXEC_MAX_OUTPUT (16*1024*1024)
+/* Allocation and I/O buffer for reading guest-exec out_data/err_data - 4KB */
+#define GUEST_EXEC_IO_SIZE (4*1024)
+
+/* Note: in some situations, like with the fsfreeze, logging may be
+ * temporarilly disabled. if it is necessary that a command be able
+ * to log for accounting purposes, check ga_logging_enabled() beforehand,
+ * and use the QERR_QGA_LOGGING_DISABLED to generate an error
+ */
+void slog(const gchar *fmt, ...)
+{
+ va_list ap;
+
+ va_start(ap, fmt);
+ g_logv("syslog", G_LOG_LEVEL_INFO, fmt, ap);
+ va_end(ap);
+}
+
+int64_t qmp_guest_sync_delimited(int64_t id, Error **errp)
+{
+ ga_set_response_delimited(ga_state);
+ return id;
+}
+
+int64_t qmp_guest_sync(int64_t id, Error **errp)
+{
+ return id;
+}
+
+void qmp_guest_ping(Error **errp)
+{
+ slog("guest-ping called");
+}
+
+static void qmp_command_info(QmpCommand *cmd, void *opaque)
+{
+ GuestAgentInfo *info = opaque;
+ GuestAgentCommandInfo *cmd_info;
+ GuestAgentCommandInfoList *cmd_info_list;
+
+ cmd_info = g_new0(GuestAgentCommandInfo, 1);
+ cmd_info->name = g_strdup(qmp_command_name(cmd));
+ cmd_info->enabled = qmp_command_is_enabled(cmd);
+ cmd_info->success_response = qmp_has_success_response(cmd);
+
+ cmd_info_list = g_new0(GuestAgentCommandInfoList, 1);
+ cmd_info_list->value = cmd_info;
+ cmd_info_list->next = info->supported_commands;
+ info->supported_commands = cmd_info_list;
+}
+
+struct GuestAgentInfo *qmp_guest_info(Error **errp)
+{
+ GuestAgentInfo *info = g_new0(GuestAgentInfo, 1);
+
+ info->version = g_strdup(QEMU_VERSION);
+ qmp_for_each_command(qmp_command_info, info);
+ return info;
+}
+
+struct GuestExecIOData {
+ guchar *data;
+ gsize size;
+ gsize length;
+ gint closed;
+ bool truncated;
+ const char *name;
+};
+typedef struct GuestExecIOData GuestExecIOData;
+
+struct GuestExecInfo {
+ GPid pid;
+ int64_t pid_numeric;
+ gint status;
+ bool has_output;
+ gint finished;
+ GuestExecIOData in;
+ GuestExecIOData out;
+ GuestExecIOData err;
+ QTAILQ_ENTRY(GuestExecInfo) next;
+};
+typedef struct GuestExecInfo GuestExecInfo;
+
+static struct {
+ QTAILQ_HEAD(, GuestExecInfo) processes;
+} guest_exec_state = {
+ .processes = QTAILQ_HEAD_INITIALIZER(guest_exec_state.processes),
+};
+
+static int64_t gpid_to_int64(GPid pid)
+{
+#ifdef G_OS_WIN32
+ return GetProcessId(pid);
+#else
+ return (int64_t)pid;
+#endif
+}
+
+static GuestExecInfo *guest_exec_info_add(GPid pid)
+{
+ GuestExecInfo *gei;
+
+ gei = g_new0(GuestExecInfo, 1);
+ gei->pid = pid;
+ gei->pid_numeric = gpid_to_int64(pid);
+ QTAILQ_INSERT_TAIL(&guest_exec_state.processes, gei, next);
+
+ return gei;
+}
+
+static GuestExecInfo *guest_exec_info_find(int64_t pid_numeric)
+{
+ GuestExecInfo *gei;
+
+ QTAILQ_FOREACH(gei, &guest_exec_state.processes, next) {
+ if (gei->pid_numeric == pid_numeric) {
+ return gei;
+ }
+ }
+
+ return NULL;
+}
+
+GuestExecStatus *qmp_guest_exec_status(int64_t pid, Error **err)
+{
+ GuestExecInfo *gei;
+ GuestExecStatus *ges;
+
+ slog("guest-exec-status called, pid: %u", (uint32_t)pid);
+
+ gei = guest_exec_info_find(pid);
+ if (gei == NULL) {
+ error_setg(err, QERR_INVALID_PARAMETER, "pid");
+ return NULL;
+ }
+
+ ges = g_new0(GuestExecStatus, 1);
+
+ bool finished = g_atomic_int_get(&gei->finished);
+
+ /* need to wait till output channels are closed
+ * to be sure we captured all output at this point */
+ if (gei->has_output) {
+ finished = finished && g_atomic_int_get(&gei->out.closed);
+ finished = finished && g_atomic_int_get(&gei->err.closed);
+ }
+
+ ges->exited = finished;
+ if (finished) {
+ /* Glib has no portable way to parse exit status.
+ * On UNIX, we can get either exit code from normal termination
+ * or signal number.
+ * On Windows, it is either the same exit code or the exception
+ * value for an unhandled exception that caused the process
+ * to terminate.
+ * See MSDN for GetExitCodeProcess() and ntstatus.h for possible
+ * well-known codes, e.g. C0000005 ACCESS_DENIED - analog of SIGSEGV
+ * References:
+ * https://msdn.microsoft.com/en-us/library/windows/desktop/ms683189(v=vs.85).aspx
+ * https://msdn.microsoft.com/en-us/library/aa260331(v=vs.60).aspx
+ */
+#ifdef G_OS_WIN32
+ /* Additionally WIN32 does not provide any additional information
+ * on whetherthe child exited or terminated via signal.
+ * We use this simple range check to distingish application exit code
+ * (usually value less then 256) and unhandled exception code with
+ * ntstatus (always value greater then 0xC0000005). */
+ if ((uint32_t)gei->status < 0xC0000000U) {
+ ges->has_exitcode = true;
+ ges->exitcode = gei->status;
+ } else {
+ ges->has_signal = true;
+ ges->signal = gei->status;
+ }
+#else
+ if (WIFEXITED(gei->status)) {
+ ges->has_exitcode = true;
+ ges->exitcode = WEXITSTATUS(gei->status);
+ } else if (WIFSIGNALED(gei->status)) {
+ ges->has_signal = true;
+ ges->signal = WTERMSIG(gei->status);
+ }
+#endif
+ if (gei->out.length > 0) {
+ ges->has_out_data = true;
+ ges->out_data = g_base64_encode(gei->out.data, gei->out.length);
+ g_free(gei->out.data);
+ ges->has_out_truncated = gei->out.truncated;
+ }
+
+ if (gei->err.length > 0) {
+ ges->has_err_data = true;
+ ges->err_data = g_base64_encode(gei->err.data, gei->err.length);
+ g_free(gei->err.data);
+ ges->has_err_truncated = gei->err.truncated;
+ }
+
+ QTAILQ_REMOVE(&guest_exec_state.processes, gei, next);
+ g_free(gei);
+ }
+
+ return ges;
+}
+
+/* Get environment variables or arguments array for execve(). */
+static char **guest_exec_get_args(const strList *entry, bool log)
+{
+ const strList *it;
+ int count = 1, i = 0; /* reserve for NULL terminator */
+ char **args;
+ char *str; /* for logging array of arguments */
+ size_t str_size = 1;
+
+ for (it = entry; it != NULL; it = it->next) {
+ count++;
+ str_size += 1 + strlen(it->value);
+ }
+
+ str = g_malloc(str_size);
+ *str = 0;
+ args = g_malloc(count * sizeof(char *));
+ for (it = entry; it != NULL; it = it->next) {
+ args[i++] = it->value;
+ pstrcat(str, str_size, it->value);
+ if (it->next) {
+ pstrcat(str, str_size, " ");
+ }
+ }
+ args[i] = NULL;
+
+ if (log) {
+ slog("guest-exec called: \"%s\"", str);
+ }
+ g_free(str);
+
+ return args;
+}
+
+static void guest_exec_child_watch(GPid pid, gint status, gpointer data)
+{
+ GuestExecInfo *gei = (GuestExecInfo *)data;
+
+ g_debug("guest_exec_child_watch called, pid: %d, status: %u",
+ (int32_t)gpid_to_int64(pid), (uint32_t)status);
+
+ gei->status = status;
+ gei->finished = true;
+
+ g_spawn_close_pid(pid);
+}
+
+/** Reset ignored signals back to default. */
+static void guest_exec_task_setup(gpointer data)
+{
+#if !defined(G_OS_WIN32)
+ struct sigaction sigact;
+
+ memset(&sigact, 0, sizeof(struct sigaction));
+ sigact.sa_handler = SIG_DFL;
+
+ if (sigaction(SIGPIPE, &sigact, NULL) != 0) {
+ slog("sigaction() failed to reset child process's SIGPIPE: %s",
+ strerror(errno));
+ }
+#endif
+}
+
+static gboolean guest_exec_input_watch(GIOChannel *ch,
+ GIOCondition cond, gpointer p_)
+{
+ GuestExecIOData *p = (GuestExecIOData *)p_;
+ gsize bytes_written = 0;
+ GIOStatus status;
+ GError *gerr = NULL;
+
+ /* nothing left to write */
+ if (p->size == p->length) {
+ goto done;
+ }
+
+ status = g_io_channel_write_chars(ch, (gchar *)p->data + p->length,
+ p->size - p->length, &bytes_written, &gerr);
+
+ /* can be not 0 even if not G_IO_STATUS_NORMAL */
+ if (bytes_written != 0) {
+ p->length += bytes_written;
+ }
+
+ /* continue write, our callback will be called again */
+ if (status == G_IO_STATUS_NORMAL || status == G_IO_STATUS_AGAIN) {
+ return true;
+ }
+
+ if (gerr) {
+ g_warning("qga: i/o error writing to input_data channel: %s",
+ gerr->message);
+ g_error_free(gerr);
+ }
+
+done:
+ g_io_channel_shutdown(ch, true, NULL);
+ g_io_channel_unref(ch);
+ g_atomic_int_set(&p->closed, 1);
+ g_free(p->data);
+
+ return false;
+}
+
+static gboolean guest_exec_output_watch(GIOChannel *ch,
+ GIOCondition cond, gpointer p_)
+{
+ GuestExecIOData *p = (GuestExecIOData *)p_;
+ gsize bytes_read;
+ GIOStatus gstatus;
+
+ if (cond == G_IO_HUP || cond == G_IO_ERR) {
+ goto close;
+ }
+
+ if (p->size == p->length) {
+ gpointer t = NULL;
+ if (!p->truncated && p->size < GUEST_EXEC_MAX_OUTPUT) {
+ t = g_try_realloc(p->data, p->size + GUEST_EXEC_IO_SIZE);
+ }
+ if (t == NULL) {
+ /* ignore truncated output */
+ gchar buf[GUEST_EXEC_IO_SIZE];
+
+ p->truncated = true;
+ gstatus = g_io_channel_read_chars(ch, buf, sizeof(buf),
+ &bytes_read, NULL);
+ if (gstatus == G_IO_STATUS_EOF || gstatus == G_IO_STATUS_ERROR) {
+ goto close;
+ }
+
+ return true;
+ }
+ p->size += GUEST_EXEC_IO_SIZE;
+ p->data = t;
+ }
+
+ /* Calling read API once.
+ * On next available data our callback will be called again */
+ gstatus = g_io_channel_read_chars(ch, (gchar *)p->data + p->length,
+ p->size - p->length, &bytes_read, NULL);
+ if (gstatus == G_IO_STATUS_EOF || gstatus == G_IO_STATUS_ERROR) {
+ goto close;
+ }
+
+ p->length += bytes_read;
+
+ return true;
+
+close:
+ g_io_channel_unref(ch);
+ g_atomic_int_set(&p->closed, 1);
+ return false;
+}
+
+GuestExec *qmp_guest_exec(const char *path,
+ bool has_arg, strList *arg,
+ bool has_env, strList *env,
+ bool has_input_data, const char *input_data,
+ bool has_capture_output, bool capture_output,
+ Error **err)
+{
+ GPid pid;
+ GuestExec *ge = NULL;
+ GuestExecInfo *gei;
+ char **argv, **envp;
+ strList arglist;
+ gboolean ret;
+ GError *gerr = NULL;
+ gint in_fd, out_fd, err_fd;
+ GIOChannel *in_ch, *out_ch, *err_ch;
+ GSpawnFlags flags;
+ bool has_output = (has_capture_output && capture_output);
+
+ arglist.value = (char *)path;
+ arglist.next = has_arg ? arg : NULL;
+
+ argv = guest_exec_get_args(&arglist, true);
+ envp = has_env ? guest_exec_get_args(env, false) : NULL;
+
+ flags = G_SPAWN_SEARCH_PATH | G_SPAWN_DO_NOT_REAP_CHILD;
+#if GLIB_CHECK_VERSION(2, 33, 2)
+ flags |= G_SPAWN_SEARCH_PATH_FROM_ENVP;
+#endif
+ if (!has_output) {
+ flags |= G_SPAWN_STDOUT_TO_DEV_NULL | G_SPAWN_STDERR_TO_DEV_NULL;
+ }
+
+ ret = g_spawn_async_with_pipes(NULL, argv, envp, flags,
+ guest_exec_task_setup, NULL, &pid, has_input_data ? &in_fd : NULL,
+ has_output ? &out_fd : NULL, has_output ? &err_fd : NULL, &gerr);
+ if (!ret) {
+ error_setg(err, QERR_QGA_COMMAND_FAILED, gerr->message);
+ g_error_free(gerr);
+ goto done;
+ }
+
+ ge = g_new0(GuestExec, 1);
+ ge->pid = gpid_to_int64(pid);
+
+ gei = guest_exec_info_add(pid);
+ gei->has_output = has_output;
+ g_child_watch_add(pid, guest_exec_child_watch, gei);
+
+ if (has_input_data) {
+ gei->in.data = g_base64_decode(input_data, &gei->in.size);
+#ifdef G_OS_WIN32
+ in_ch = g_io_channel_win32_new_fd(in_fd);
+#else
+ in_ch = g_io_channel_unix_new(in_fd);
+#endif
+ g_io_channel_set_encoding(in_ch, NULL, NULL);
+ g_io_channel_set_buffered(in_ch, false);
+ g_io_channel_set_flags(in_ch, G_IO_FLAG_NONBLOCK, NULL);
+ g_io_add_watch(in_ch, G_IO_OUT, guest_exec_input_watch, &gei->in);
+ }
+
+ if (has_output) {
+#ifdef G_OS_WIN32
+ out_ch = g_io_channel_win32_new_fd(out_fd);
+ err_ch = g_io_channel_win32_new_fd(err_fd);
+#else
+ out_ch = g_io_channel_unix_new(out_fd);
+ err_ch = g_io_channel_unix_new(err_fd);
+#endif
+ g_io_channel_set_encoding(out_ch, NULL, NULL);
+ g_io_channel_set_encoding(err_ch, NULL, NULL);
+ g_io_channel_set_buffered(out_ch, false);
+ g_io_channel_set_buffered(err_ch, false);
+ g_io_add_watch(out_ch, G_IO_IN | G_IO_HUP,
+ guest_exec_output_watch, &gei->out);
+ g_io_add_watch(err_ch, G_IO_IN | G_IO_HUP,
+ guest_exec_output_watch, &gei->err);
+ }
+
+done:
+ g_free(argv);
+ g_free(envp);
+
+ return ge;
+}
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