Set loginuid properly when running commands on behalf of a user

This makes the audit log have the right information

4 files changed, 87 insertions, 178 deletions

diff --git a/src/daemon.c b/src/daemon.c
index 50ae3b9..7f6a088 100644
--- a/src/daemon.c
+++ b/src/daemon.c
@@ -1022,8 +1022,6 @@ daemon_create_user_authorized_cb (Daemon                *daemon,
         CreateUserData *cd = data;
         User *user;
         GError *error;
-        gchar *std_err, *std_out;
-        gint status;
         gchar *argv[8];
 
         if (getpwnam (cd->user_name) != NULL) {
@@ -1055,27 +1053,13 @@ daemon_create_user_authorized_cb (Daemon                *daemon,
                 argv[5] = NULL;
         }
 
-        std_out = NULL;
-        std_err = NULL;
         error = NULL;
-        if (!g_spawn_sync (NULL, argv, NULL, 0, NULL, NULL, &std_out, &std_err, &status, &error)) {
+        if (!spawn_with_login_uid (context, argv, &error)) {
                 throw_error (context, ERROR_FAILED, "running '%s' failed: %s", argv[0], error->message);
                 g_error_free (error);
-                g_free (std_out);
-                g_free (std_err);
                 return;
         }
 
-        if (WEXITSTATUS (status) != 0) {
-                throw_error (context, ERROR_FAILED, "useradd returned an error: %s", std_err);
-                g_free (std_out);
-                g_free (std_err);
-                return;
-        }
-
-        g_free (std_out);
-        g_free (std_err);
-
         user = daemon_local_find_user_by_name (daemon, cd->user_name);
 
         dbus_g_method_return (context, user_local_get_object_path (user));
@@ -1121,8 +1105,6 @@ daemon_delete_user_authorized_cb (Daemon                *daemon,
 {
         DeleteUserData *ud = data;
         GError *error;
-        gchar *std_err, *std_out;
-        gint status;
         gchar *filename;
         struct passwd *pwent;
         gchar *argv[4];
@@ -1148,21 +1130,10 @@ daemon_delete_user_authorized_cb (Daemon                *daemon,
                 argv[2] = NULL;
         }
 
-        std_out = NULL;
-        std_err = NULL;
         error = NULL;
-        if (!g_spawn_sync (NULL, argv, NULL, 0, NULL, NULL, &std_out, &std_err, &status, &error)) {
+        if (!spawn_with_login_uid (context, argv, &error)) {
                 throw_error (context, ERROR_FAILED, "running '%s' failed: %s", argv[0], error->message);
                 g_error_free (error);
-                g_free (std_out);
-                g_free (std_err);
-                return;
-        }
-
-        if (WEXITSTATUS (status) != 0) {
-                throw_error (context, ERROR_FAILED, "userdel returned an error: %s", std_err);
-                g_free (std_out);
-                g_free (std_err);
                 return;
         }
 
diff --git a/src/user.c b/src/user.c
index 6501922..a1dff91 100644
--- a/src/user.c
+++ b/src/user.c
@@ -769,8 +769,6 @@ user_change_real_name_authorized_cb (Daemon                *daemon,
 {
         gchar *name = data;
         GError *error;
-        gint status;
-        gchar *std_out, *std_err;
         gchar *argv[5];
 
         if (g_strcmp0 (user->real_name, name) != 0) {
@@ -784,27 +782,13 @@ user_change_real_name_authorized_cb (Daemon                *daemon,
                 argv[3] = user->user_name;
                 argv[4] = NULL;
 
-                std_out = NULL;
-                std_err = NULL;
                 error = NULL;
-                if (!g_spawn_sync (NULL, argv, NULL, 0, NULL, NULL, &std_out, &std_err, &status, &error)) {
+                if (!spawn_with_login_uid (context, argv, &error)) {
                         throw_error (context, ERROR_FAILED, "running '%s' failed: %s", argv[0], error->message);
                         g_error_free (error);
-                        g_free (std_out);
-                        g_free (std_err);
                         return;
                 }
 
-                if (WEXITSTATUS (status) != 0) {
-                        throw_error (context, ERROR_FAILED, "usermod returned an error: %s", std_err);
-                        g_free (std_out);
-                        g_free (std_err);
-                        return;
-                }
-
-                g_free (std_out);
-                g_free (std_err);
-
                 g_free (user->real_name);
                 user->real_name = g_strdup (name);
 
@@ -865,8 +849,6 @@ user_change_user_name_authorized_cb (Daemon                *daemon,
         gchar *name = data;
         gchar *old_name;
         GError *error;
-        gint status;
-        gchar *std_out, *std_err;
         gchar *argv[5];
 
         if (g_strcmp0 (user->user_name, name) != 0) {
@@ -881,27 +863,13 @@ user_change_user_name_authorized_cb (Daemon                *daemon,
                 argv[3] = user->user_name;
                 argv[4] = NULL;
 
-                std_out = NULL;
-                std_err = NULL;
                 error = NULL;
-                if (!g_spawn_sync (NULL, argv, NULL, 0, NULL, NULL, &std_out, &std_err, &status, &error)) {
+                if (!spawn_with_login_uid (context, argv, &error)) {
                         throw_error (context, ERROR_FAILED, "running '%s' failed: %s", argv[0], error->message);
                         g_error_free (error);
-                        g_free (std_out);
-                        g_free (std_err);
                         return;
                 }
 
-                if (WEXITSTATUS (status) != 0) {
-                        throw_error (context, ERROR_FAILED, "usermod returned an error: %s", std_err);
-                        g_free (std_out);
-                        g_free (std_err);
-                        return;
-                }
-
-                g_free (std_out);
-                g_free (std_err);
-
                 g_free (user->user_name);
                 user->user_name = g_strdup (name);
 
@@ -1154,8 +1122,6 @@ user_change_home_dir_authorized_cb (Daemon                *daemon,
 {
         gchar *home_dir = data;
         GError *error;
-        gint status;
-        gchar *std_out, *std_err;
         gchar *argv[6];
 
         if (g_strcmp0 (user->home_dir, home_dir) != 0) {
@@ -1170,27 +1136,13 @@ user_change_home_dir_authorized_cb (Daemon                *daemon,
                 argv[4] = user->user_name;
                 argv[5] = NULL;
 
-                std_out = NULL;
-                std_err = NULL;
                 error = NULL;
-                if (!g_spawn_sync (NULL, argv, NULL, 0, NULL, NULL, &std_out, &std_err, &status, &error)) {
+                if (!spawn_with_login_uid (context, argv, &error)) {
                         throw_error (context, ERROR_FAILED, "running '%s' failed: %s", argv[0], error->message);
                         g_error_free (error);
-                        g_free (std_out);
-                        g_free (std_err);
                         return;
                 }
 
-                if (WEXITSTATUS (status) != 0) {
-                        throw_error (context, ERROR_FAILED, "usermod returned an error: %s", std_err);
-                        g_free (std_out);
-                        g_free (std_err);
-                        return;
-                }
-
-                g_free (std_out);
-                g_free (std_err);
-
                 g_free (user->home_dir);
                 user->home_dir = g_strdup (home_dir);
 
@@ -1247,8 +1199,6 @@ user_change_shell_authorized_cb (Daemon                *daemon,
 {
         gchar *shell = data;
         GError *error;
-        gint status;
-        gchar *std_out, *std_err;
         gchar *argv[5];
 
         if (g_strcmp0 (user->shell, shell) != 0) {
@@ -1262,27 +1212,13 @@ user_change_shell_authorized_cb (Daemon                *daemon,
                 argv[3] = user->user_name;
                 argv[4] = NULL;
 
-                std_out = NULL;
-                std_err = NULL;
                 error = NULL;
-                if (!g_spawn_sync (NULL, argv, NULL, 0, NULL, NULL, &std_out, &std_err, &status, &error)) {
+                if (!spawn_with_login_uid (context, argv, &error)) {
                         throw_error (context, ERROR_FAILED, "running '%s' failed: %s", argv[0], error->message);
                         g_error_free (error);
-                        g_free (std_out);
-                        g_free (std_err);
-                        return;
-                }
-
-                if (WEXITSTATUS (status) != 0) {
-                        throw_error (context, ERROR_FAILED, "usermod returned an error: %s", std_err);
-                        g_free (std_out);
-                        g_free (std_err);
                         return;
                 }
 
-                g_free (std_out);
-                g_free (std_err);
-
                 g_free (user->shell);
                 user->shell = g_strdup (shell);
 
@@ -1532,8 +1468,6 @@ user_change_locked_authorized_cb (Daemon                *daemon,
 {
         gboolean locked = GPOINTER_TO_INT (data);
         GError *error;
-        gint status;
-        gchar *std_out, *std_err;
         gchar *argv[4];
 
         if (user->locked != locked) {
@@ -1545,27 +1479,13 @@ user_change_locked_authorized_cb (Daemon                *daemon,
                 argv[2] = user->user_name;
                 argv[3] = NULL;
 
-                std_out = NULL;
-                std_err = NULL;
                 error = NULL;
-                if (!g_spawn_sync (NULL, argv, NULL, 0, NULL, NULL, &std_out, &std_err, &status, &error)) {
+                if (!spawn_with_login_uid (context, argv, &error)) {
                         throw_error (context, ERROR_FAILED, "running '%s' failed: %s", argv[0], error->message);
                         g_error_free (error);
-                        g_free (std_out);
-                        g_free (std_err);
-                        return;
-                }
-
-                if (WEXITSTATUS (status) != 0) {
-                        throw_error (context, ERROR_FAILED, "usermod returned an error: %s", std_err);
-                        g_free (std_out);
-                        g_free (std_err);
                         return;
                 }
 
-                g_free (std_out);
-                g_free (std_err);
-
                 user->locked = locked;
 
                 g_signal_emit (user, signals[CHANGED], 0);
@@ -1602,8 +1522,6 @@ user_change_account_type_authorized_cb (Daemon                *daemon,
 {
         gint account_type = GPOINTER_TO_INT (data);
         GError *error;
-        gint status;
-        gchar *std_out, *std_err;
         gid_t groups[20];
         gint n_groups;
         GString *str;
@@ -1664,27 +1582,13 @@ user_change_account_type_authorized_cb (Daemon                *daemon,
 
                 g_string_free (str, FALSE);
 
-                std_out = NULL;
-                std_err = NULL;
                 error = NULL;
-                if (!g_spawn_sync (NULL, argv, NULL, 0, NULL, NULL, &std_out, &std_err, &status, &error)) {
+                if (!spawn_with_login_uid (context, argv, &error)) {
                         throw_error (context, ERROR_FAILED, "running '%s' failed: %s", argv[0], error->message);
                         g_error_free (error);
-                        g_free (std_out);
-                        g_free (std_err);
                         return;
                 }
 
-                if (WEXITSTATUS (status) != 0) {
-                        throw_error (context, ERROR_FAILED, "usermod returned an error: %s", std_err);
-                        g_free (std_out);
-                        g_free (std_err);
-                        return;
-                }
-
-                g_free (std_out);
-                g_free (std_err);
-
                 user->account_type = account_type;
 
                 g_signal_emit (user, signals[CHANGED], 0);
@@ -1726,8 +1630,6 @@ user_change_password_mode_authorized_cb (Daemon                *daemon,
 {
         gint mode = GPOINTER_TO_INT (data);
         GError *error;
-        gint status;
-        gchar *std_out, *std_err;
         gchar *argv[4];
 
         if (user->password_mode != mode) {
@@ -1745,27 +1647,13 @@ user_change_password_mode_authorized_cb (Daemon                *daemon,
                         argv[2] = user->user_name;
                         argv[3] = NULL;
 
-                        std_out = NULL;
-                        std_err = NULL;
                         error = NULL;
-                        if (!g_spawn_sync (NULL, argv, NULL, 0, NULL, NULL, &std_out, &std_err, &status, &error)) {
+                        if (!spawn_with_login_uid (context, argv, &error)) {
                                 throw_error (context, ERROR_FAILED, "running '%s' failed: %s", argv[0], error->message);
                                 g_error_free (error);
-                                g_free (std_out);
-                                g_free (std_err);
                                 return;
                         }
 
-                        if (WEXITSTATUS (status) != 0) {
-                                throw_error (context, ERROR_FAILED, "passwd returned an error: %s", std_err);
-                                g_free (std_out);
-                                g_free (std_err);
-                                return;
-                        }
-
-                        g_free (std_out);
-                        g_free (std_err);
-
                         g_free (user->password_hint);
                         user->password_hint = NULL;
 
@@ -1785,20 +1673,10 @@ user_change_password_mode_authorized_cb (Daemon                *daemon,
                         argv[2] = user->user_name;
                         argv[3] = NULL;
 
-                        std_out = NULL;
-                        std_err = NULL;
                         error = NULL;
-                        if (!g_spawn_sync (NULL, argv, NULL, 0, NULL, NULL, &std_out, &std_err, &status, &error)) {
+                        if (!spawn_with_login_uid (context, argv, &error)) {
                                 throw_error (context, ERROR_FAILED, "running '%s' failed: %s", argv[0], error->message);
                                 g_error_free (error);
-                                g_free (std_out);
-                                g_free (std_err);
-                                return;
-                        }
-                        if (WEXITSTATUS (status) != 0) {
-                                throw_error (context, ERROR_FAILED, "usermod returned an error: %s", std_err);
-                                g_free (std_out);
-                                g_free (std_err);
                                 return;
                         }
 
@@ -1870,8 +1748,6 @@ user_change_password_authorized_cb (Daemon                *daemon,
 {
         gchar **strings = data;
         GError *error;
-        gint status;
-        gchar *std_out, *std_err;
         gchar *argv[5];
 
         sys_log (context,
@@ -1886,27 +1762,13 @@ user_change_password_authorized_cb (Daemon                *daemon,
         argv[3] = user->user_name;
         argv[4] = NULL;
 
-        std_out = NULL;
-        std_err = NULL;
         error = NULL;
-        if (!g_spawn_sync (NULL, argv, NULL, 0, NULL, NULL, &std_out, &std_err, &status, &error)) {
+        if (!spawn_with_login_uid (context, argv, &error)) {
                 throw_error (context, ERROR_FAILED, "running '%s' failed: %s", argv[0], error->message);
                 g_error_free (error);
-                g_free (std_out);
-                g_free (std_err);
                 return;
         }
 
-        if (WEXITSTATUS (status) != 0) {
-                throw_error (context, ERROR_FAILED, "usermod returned an error: %s", std_err);
-                g_free (std_out);
-                g_free (std_err);
-                return;
-        }
-
-        g_free (std_out);
-        g_free (std_err);
-
         if (user->password_mode != PASSWORD_MODE_REGULAR) {
                 user->password_mode = PASSWORD_MODE_REGULAR;
                 g_object_notify (G_OBJECT (user), "password-mode");
diff --git a/src/util.c b/src/util.c
index e12c687..2cd2af8 100644
--- a/src/util.c
+++ b/src/util.c
@@ -21,7 +21,14 @@
 
 #include "config.h"
 
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <wait.h>
+
 #include <syslog.h>
+
 #include <dbus/dbus-glib.h>
 #include <dbus/dbus-glib-lowlevel.h>
 
@@ -142,3 +149,68 @@ sys_log (DBusGMethodInvocation *context,
 
         g_free (real_format);
 }
+
+static gint
+get_caller_uid (DBusGMethodInvocation *context)
+{
+        PolkitSubject *subject;
+        gchar *cmdline;
+        gint pid;
+        gint uid;
+
+        subject = polkit_system_bus_name_new (dbus_g_method_get_sender (context));
+        cmdline = _polkit_subject_get_cmdline (subject, &pid, &uid);
+
+        g_object_unref (subject);
+        g_free (cmdline);
+
+        return uid;
+}
+
+static void
+setup_loginuid (gpointer data)
+{
+        const char *id = data;
+        int fd;
+
+        fd = open ("/proc/self/loginuid", O_WRONLY);
+        write (fd, id, strlen (id));
+        close (fd);
+}
+
+gboolean
+spawn_with_login_uid (DBusGMethodInvocation  *context,
+                      gchar                  *argv[],
+                      GError                **error)
+{
+        GError *local_error;
+        gchar loginuid[20];
+        gchar *std_err;
+        gint status;
+
+        g_snprintf (loginuid, 20, "%d", get_caller_uid (context));
+
+        local_error = NULL;
+        std_err = NULL;
+
+        if (!g_spawn_sync (NULL, argv, NULL, 0, setup_loginuid, loginuid, NULL, &std_err, &status, &local_error)) {
+                g_propagate_error (error, local_error);
+                g_free (std_err);
+                return FALSE;
+        }
+
+        if (WEXITSTATUS (status) != 0) {
+                g_set_error (error,
+                             G_SPAWN_ERROR,
+                             G_SPAWN_ERROR_FAILED,
+                             "%s returned an error (%d): %s",
+                             argv[0], WEXITSTATUS(status), std_err);
+                g_free (std_err);
+                return FALSE;
+        }
+
+        g_free (std_err);
+
+        return TRUE;
+}
+
diff --git a/src/util.h b/src/util.h
index ff5e0df..3f51af1 100644
--- a/src/util.h
+++ b/src/util.h
@@ -31,6 +31,10 @@ void sys_log (DBusGMethodInvocation *context,
               const gchar           *format,
                                      ...);
 
+gboolean spawn_with_login_uid (DBusGMethodInvocation  *context,
+                               gchar                  *argv[],
+                               GError                **error);
+
 G_END_DECLS
 
 #endif /* __UTIL_H__ */