1 files changed, 432 insertions, 3 deletions

diff --git a/qemu/qga/commands.c b/qemu/qga/commands.c
index 783496791..b653a460b 100644
--- a/qemu/qga/commands.c
+++ b/qemu/qga/commands.c
@@ -10,10 +10,18 @@
  * See the COPYING file in the top-level directory.
  */
 
+#include "qemu/osdep.h"
 #include <glib.h>
 #include "qga/guest-agent-core.h"
 #include "qga-qmp-commands.h"
 #include "qapi/qmp/qerror.h"
+#include "qemu/base64.h"
+#include "qemu/cutils.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
@@ -51,12 +59,12 @@ static void qmp_command_info(QmpCommand *cmd, void *opaque)
     GuestAgentCommandInfo *cmd_info;
     GuestAgentCommandInfoList *cmd_info_list;
 
-    cmd_info = g_malloc0(sizeof(GuestAgentCommandInfo));
+    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_malloc0(sizeof(GuestAgentCommandInfoList));
+    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;
@@ -64,9 +72,430 @@ static void qmp_command_info(QmpCommand *cmd, void *opaque)
 
 struct GuestAgentInfo *qmp_guest_info(Error **errp)
 {
-    GuestAgentInfo *info = g_malloc0(sizeof(GuestAgentInfo));
+    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_shutdown(ch, true, NULL);
+    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);
+    uint8_t *input = NULL;
+    size_t ninput = 0;
+
+    arglist.value = (char *)path;
+    arglist.next = has_arg ? arg : NULL;
+
+    if (has_input_data) {
+        input = qbase64_decode(input_data, -1, &ninput, err);
+        if (!input) {
+            return 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 = input;
+        gei->in.size = ninput;
+#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_channel_set_close_on_unref(in_ch, true);
+        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_channel_set_close_on_unref(out_ch, true);
+        g_io_channel_set_close_on_unref(err_ch, true);
+        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;
+}
+
+/* Convert GuestFileWhence (either a raw integer or an enum value) into
+ * the guest's SEEK_ constants.  */
+int ga_parse_whence(GuestFileWhence *whence, Error **errp)
+{
+    /* Exploit the fact that we picked values to match QGA_SEEK_*. */
+    if (whence->type == QTYPE_QSTRING) {
+        whence->type = QTYPE_QINT;
+        whence->u.value = whence->u.name;
+    }
+    switch (whence->u.value) {
+    case QGA_SEEK_SET:
+        return SEEK_SET;
+    case QGA_SEEK_CUR:
+        return SEEK_CUR;
+    case QGA_SEEK_END:
+        return SEEK_END;
+    }
+    error_setg(errp, "invalid whence code %"PRId64, whence->u.value);
+    return -1;
+}