gnome-shell/src/main.c
Florian Müllner 1aff64a38b main: Stop owning the public org.freedesktop.Notifications name
For sandboxed apps, permission to talk to org.freedesktop.Notifications
looks innocent enough. However as all exported services share the same
connection to the session bus, that permission actually grants an app
access to *any* shell D-Bus API.

While we want apps to use the notification portal, it is still common
for apps to use libnotify, raw D-Bus calls or even notify-send.

We don't want to give those apps a way to circumvent most of the sandbox
restrictions, so stop owning the org.freedesktop.Notifications name.

In a next step we will implement a separate notification-daemon that
exposes the API on the well-known address and proxies any requests to
the real implementation in gnome-shell.

https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/547
2020-03-12 16:09:27 +00:00

559 lines
16 KiB
C

/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
#include "config.h"
#ifdef HAVE_MALLINFO
#include <malloc.h>
#endif
#include <stdlib.h>
#include <string.h>
#include <cogl-pango/cogl-pango.h>
#include <clutter/clutter.h>
#include <clutter/x11/clutter-x11.h>
#include <gtk/gtk.h>
#include <glib/gi18n-lib.h>
#include <girepository.h>
#include <meta/main.h>
#include <meta/meta-plugin.h>
#include <meta/prefs.h>
#include <atk-bridge.h>
#include "shell-global.h"
#include "shell-global-private.h"
#include "shell-perf-log.h"
#include "st.h"
extern GType gnome_shell_plugin_get_type (void);
#define SHELL_DBUS_SERVICE "org.gnome.Shell"
#define MAGNIFIER_DBUS_SERVICE "org.gnome.Magnifier"
#define WM_NAME "GNOME Shell"
#define GNOME_WM_KEYBINDINGS "Mutter,GNOME Shell"
static gboolean is_gdm_mode = FALSE;
static char *session_mode = NULL;
static int caught_signal = 0;
#define DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER 1
#define DBUS_REQUEST_NAME_REPLY_ALREADY_OWNER 4
enum {
SHELL_DEBUG_BACKTRACE_WARNINGS = 1,
SHELL_DEBUG_BACKTRACE_SEGFAULTS = 2,
};
static int _shell_debug;
static gboolean _tracked_signals[NSIG] = { 0 };
static void
shell_dbus_acquire_name (GDBusProxy *bus,
guint32 request_name_flags,
guint32 *request_name_result,
const gchar *name,
gboolean fatal)
{
GError *error = NULL;
GVariant *request_name_variant;
if (!(request_name_variant = g_dbus_proxy_call_sync (bus,
"RequestName",
g_variant_new ("(su)", name, request_name_flags),
0, /* call flags */
-1, /* timeout */
NULL, /* cancellable */
&error)))
{
g_printerr ("failed to acquire %s: %s\n", name, error->message);
g_clear_error (&error);
if (!fatal)
return;
exit (1);
}
g_variant_get (request_name_variant, "(u)", request_name_result);
g_variant_unref (request_name_variant);
}
static void
shell_dbus_acquire_names (GDBusProxy *bus,
guint32 request_name_flags,
const gchar *name,
gboolean fatal, ...) G_GNUC_NULL_TERMINATED;
static void
shell_dbus_acquire_names (GDBusProxy *bus,
guint32 request_name_flags,
const gchar *name,
gboolean fatal, ...)
{
va_list al;
guint32 request_name_result;
va_start (al, fatal);
for (;;)
{
shell_dbus_acquire_name (bus,
request_name_flags,
&request_name_result,
name, fatal);
name = va_arg (al, gchar *);
if (!name)
break;
fatal = va_arg (al, gboolean);
}
va_end (al);
}
static void
shell_dbus_init (gboolean replace)
{
GDBusConnection *session;
GDBusProxy *bus;
GError *error = NULL;
guint32 request_name_flags;
guint32 request_name_result;
session = g_bus_get_sync (G_BUS_TYPE_SESSION, NULL, &error);
if (error) {
g_printerr ("Failed to connect to session bus: %s", error->message);
exit (1);
}
bus = g_dbus_proxy_new_sync (session,
G_DBUS_PROXY_FLAGS_NONE,
NULL, /* interface info */
"org.freedesktop.DBus",
"/org/freedesktop/DBus",
"org.freedesktop.DBus",
NULL, /* cancellable */
&error);
if (!bus)
{
g_printerr ("Failed to get a session bus proxy: %s", error->message);
exit (1);
}
request_name_flags = G_BUS_NAME_OWNER_FLAGS_ALLOW_REPLACEMENT;
if (replace)
request_name_flags |= G_BUS_NAME_OWNER_FLAGS_REPLACE;
shell_dbus_acquire_name (bus,
request_name_flags,
&request_name_result,
SHELL_DBUS_SERVICE, TRUE);
if (!(request_name_result == DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER
|| request_name_result == DBUS_REQUEST_NAME_REPLY_ALREADY_OWNER))
{
g_printerr (SHELL_DBUS_SERVICE " already exists on bus and --replace not specified\n");
exit (1);
}
/*
* We always specify REPLACE_EXISTING to ensure we kill off
* the existing service if it was running.
*/
request_name_flags |= G_BUS_NAME_OWNER_FLAGS_REPLACE;
shell_dbus_acquire_names (bus,
request_name_flags,
/* Also grab org.gnome.Panel to replace any existing panel process */
"org.gnome.Panel", TRUE,
/* ...and the org.gnome.Magnifier service. */
MAGNIFIER_DBUS_SERVICE, FALSE,
NULL);
g_object_unref (bus);
g_object_unref (session);
}
static void
shell_introspection_init (void)
{
g_irepository_prepend_search_path (MUTTER_TYPELIB_DIR);
g_irepository_prepend_search_path (GNOME_SHELL_PKGLIBDIR);
/* We need to explicitly add the directories where the private libraries are
* installed to the GIR's library path, so that they can be found at runtime
* when linking using DT_RUNPATH (instead of DT_RPATH), which is the default
* for some linkers (e.g. gold) and in some distros (e.g. Debian).
*/
g_irepository_prepend_library_path (MUTTER_TYPELIB_DIR);
g_irepository_prepend_library_path (GNOME_SHELL_PKGLIBDIR);
}
static void
shell_fonts_init (void)
{
CoglPangoFontMap *fontmap;
/* Disable text mipmapping; it causes problems on pre-GEM Intel
* drivers and we should just be rendering text at the right
* size rather than scaling it. If we do effects where we dynamically
* zoom labels, then we might want to reconsider.
*/
fontmap = COGL_PANGO_FONT_MAP (clutter_get_font_map ());
cogl_pango_font_map_set_use_mipmapping (fontmap, FALSE);
}
static void
shell_profiler_init (void)
{
ShellGlobal *global;
GjsProfiler *profiler;
GjsContext *context;
const char *enabled;
const char *fd_str;
int fd = -1;
/* Sysprof uses the "GJS_TRACE_FD=N" environment variable to connect GJS
* profiler data to the combined Sysprof capture. Since we are in control of
* the GjsContext, we need to proxy this FD across to the GJS profiler.
*/
fd_str = g_getenv ("GJS_TRACE_FD");
enabled = g_getenv ("GJS_ENABLE_PROFILER");
if (fd_str == NULL || enabled == NULL)
return;
global = shell_global_get ();
g_return_if_fail (global);
context = _shell_global_get_gjs_context (global);
g_return_if_fail (context);
profiler = gjs_context_get_profiler (context);
g_return_if_fail (profiler);
if (fd_str)
{
fd = atoi (fd_str);
if (fd > 2)
{
gjs_profiler_set_fd (profiler, fd);
gjs_profiler_start (profiler);
}
}
}
static void
shell_profiler_shutdown (void)
{
ShellGlobal *global;
GjsProfiler *profiler;
GjsContext *context;
global = shell_global_get ();
context = _shell_global_get_gjs_context (global);
profiler = gjs_context_get_profiler (context);
if (profiler)
gjs_profiler_stop (profiler);
}
static void
malloc_statistics_callback (ShellPerfLog *perf_log,
gpointer data)
{
#ifdef HAVE_MALLINFO
struct mallinfo info = mallinfo ();
shell_perf_log_update_statistic_i (perf_log,
"malloc.arenaSize",
info.arena);
shell_perf_log_update_statistic_i (perf_log,
"malloc.mmapSize",
info.hblkhd);
shell_perf_log_update_statistic_i (perf_log,
"malloc.usedSize",
info.uordblks);
#endif
}
static void
shell_perf_log_init (void)
{
ShellPerfLog *perf_log = shell_perf_log_get_default ();
/* For probably historical reasons, mallinfo() defines the returned values,
* even those in bytes as int, not size_t. We're determined not to use
* more than 2G of malloc'ed memory, so are OK with that.
*/
shell_perf_log_define_statistic (perf_log,
"malloc.arenaSize",
"Amount of memory allocated by malloc() with brk(), in bytes",
"i");
shell_perf_log_define_statistic (perf_log,
"malloc.mmapSize",
"Amount of memory allocated by malloc() with mmap(), in bytes",
"i");
shell_perf_log_define_statistic (perf_log,
"malloc.usedSize",
"Amount of malloc'ed memory currently in use",
"i");
shell_perf_log_add_statistics_callback (perf_log,
malloc_statistics_callback,
NULL, NULL);
}
static void
shell_a11y_init (void)
{
cally_accessibility_init ();
if (clutter_get_accessibility_enabled () == FALSE)
{
g_warning ("Accessibility: clutter has no accessibility enabled"
" skipping the atk-bridge load");
}
else
{
atk_bridge_adaptor_init (NULL, NULL);
}
}
static void
shell_init_debug (const char *debug_env)
{
static const GDebugKey keys[] = {
{ "backtrace-warnings", SHELL_DEBUG_BACKTRACE_WARNINGS },
{ "backtrace-segfaults", SHELL_DEBUG_BACKTRACE_SEGFAULTS },
};
_shell_debug = g_parse_debug_string (debug_env, keys,
G_N_ELEMENTS (keys));
}
static void
default_log_handler (const char *log_domain,
GLogLevelFlags log_level,
const char *message,
gpointer data)
{
if (!log_domain || !g_str_has_prefix (log_domain, "tp-glib"))
g_log_default_handler (log_domain, log_level, message, data);
/* Filter out Gjs logs, those already have the stack */
if (log_domain && strcmp (log_domain, "Gjs") == 0)
return;
if ((_shell_debug & SHELL_DEBUG_BACKTRACE_WARNINGS) &&
((log_level & G_LOG_LEVEL_CRITICAL) ||
(log_level & G_LOG_LEVEL_WARNING)))
gjs_dumpstack ();
}
static void
shut_up (const char *domain,
GLogLevelFlags level,
const char *message,
gpointer user_data)
{
}
static void
dump_gjs_stack_alarm_sigaction (int signo)
{
g_log_set_default_handler (g_log_default_handler, NULL);
g_warning ("Failed to dump Javascript stack, got stuck");
g_log_set_default_handler (default_log_handler, NULL);
raise (caught_signal);
}
static void
dump_gjs_stack_on_signal_handler (int signo)
{
struct sigaction sa = { .sa_handler = dump_gjs_stack_alarm_sigaction };
gsize i;
/* Ignore all the signals starting this point, a part the one we'll raise
* (which is implicitly ignored here through SA_RESETHAND), this is needed
* not to get this handler being called by other signals that we were
* tracking and that might be emitted by code called starting from now.
*/
for (i = 0; i < G_N_ELEMENTS (_tracked_signals); ++i)
{
if (_tracked_signals[i] && i != signo)
signal (i, SIG_IGN);
}
/* Waiting at least 5 seconds for the dumpstack, if it fails, we raise the error */
caught_signal = signo;
sigemptyset (&sa.sa_mask);
sigaction (SIGALRM, &sa, NULL);
alarm (5);
gjs_dumpstack ();
alarm (0);
raise (signo);
}
static void
dump_gjs_stack_on_signal (int signo)
{
struct sigaction sa = {
.sa_flags = SA_RESETHAND | SA_NODEFER,
.sa_handler = dump_gjs_stack_on_signal_handler,
};
sigemptyset (&sa.sa_mask);
sigaction (signo, &sa, NULL);
_tracked_signals[signo] = TRUE;
}
static gboolean
list_modes (const char *option_name,
const char *value,
gpointer data,
GError **error)
{
ShellGlobal *global;
GjsContext *context;
const char *script;
int status;
/* Many of our imports require global to be set, so rather than
* tayloring our imports carefully here to avoid that dependency,
* we just set it.
* ShellGlobal has some GTK+ dependencies, so initialize GTK+; we
* don't really care if it fails though (e.g. when running from a tty),
* so we mute all warnings */
g_log_set_default_handler (shut_up, NULL);
gtk_init_check (NULL, NULL);
_shell_global_init (NULL);
global = shell_global_get ();
context = _shell_global_get_gjs_context (global);
shell_introspection_init ();
script = "imports.ui.environment.init();"
"imports.ui.sessionMode.listModes();";
if (!gjs_context_eval (context, script, -1, "<main>", &status, NULL))
g_message ("Retrieving list of available modes failed.");
g_object_unref (context);
exit (status);
}
static gboolean
print_version (const gchar *option_name,
const gchar *value,
gpointer data,
GError **error)
{
g_print ("GNOME Shell %s\n", VERSION);
exit (0);
}
GOptionEntry gnome_shell_options[] = {
{
"version", 0, G_OPTION_FLAG_NO_ARG, G_OPTION_ARG_CALLBACK,
print_version,
N_("Print version"),
NULL
},
{
"gdm-mode", 0, G_OPTION_FLAG_HIDDEN, G_OPTION_ARG_NONE,
&is_gdm_mode,
N_("Mode used by GDM for login screen"),
NULL
},
{
"mode", 0, 0, G_OPTION_ARG_STRING,
&session_mode,
N_("Use a specific mode, e.g. “gdm” for login screen"),
"MODE"
},
{
"list-modes", 0, G_OPTION_FLAG_NO_ARG, G_OPTION_ARG_CALLBACK,
list_modes,
N_("List possible modes"),
NULL
},
{ NULL }
};
int
main (int argc, char **argv)
{
GOptionContext *ctx;
GError *error = NULL;
int ecode;
bindtextdomain (GETTEXT_PACKAGE, LOCALEDIR);
bind_textdomain_codeset (GETTEXT_PACKAGE, "UTF-8");
textdomain (GETTEXT_PACKAGE);
session_mode = (char *) g_getenv ("GNOME_SHELL_SESSION_MODE");
ctx = meta_get_option_context ();
g_option_context_add_main_entries (ctx, gnome_shell_options, GETTEXT_PACKAGE);
g_option_context_add_group (ctx, g_irepository_get_option_group ());
if (!g_option_context_parse (ctx, &argc, &argv, &error))
{
g_printerr ("%s: %s\n", argv[0], error->message);
exit (1);
}
g_option_context_free (ctx);
meta_plugin_manager_set_plugin_type (gnome_shell_plugin_get_type ());
meta_set_wm_name (WM_NAME);
meta_set_gnome_wm_keybindings (GNOME_WM_KEYBINDINGS);
/* Prevent meta_init() from causing gtk to load the atk-bridge*/
g_setenv ("NO_AT_BRIDGE", "1", TRUE);
meta_init ();
g_unsetenv ("NO_AT_BRIDGE");
/* FIXME: Add gjs API to set this stuff and don't depend on the
* environment. These propagate to child processes.
*/
g_setenv ("GJS_DEBUG_OUTPUT", "stderr", TRUE);
g_setenv ("GJS_DEBUG_TOPICS", "JS ERROR;JS LOG", TRUE);
shell_init_debug (g_getenv ("SHELL_DEBUG"));
shell_dbus_init (meta_get_replace_current_wm ());
shell_a11y_init ();
shell_perf_log_init ();
shell_introspection_init ();
shell_fonts_init ();
g_log_set_default_handler (default_log_handler, NULL);
/* Initialize the global object */
if (session_mode == NULL)
session_mode = is_gdm_mode ? (char *)"gdm" : (char *)"user";
_shell_global_init ("session-mode", session_mode, NULL);
dump_gjs_stack_on_signal (SIGABRT);
dump_gjs_stack_on_signal (SIGFPE);
dump_gjs_stack_on_signal (SIGIOT);
dump_gjs_stack_on_signal (SIGTRAP);
if ((_shell_debug & SHELL_DEBUG_BACKTRACE_SEGFAULTS))
{
dump_gjs_stack_on_signal (SIGBUS);
dump_gjs_stack_on_signal (SIGSEGV);
}
shell_profiler_init ();
ecode = meta_run ();
shell_profiler_shutdown ();
g_debug ("Doing final cleanup");
_shell_global_destroy_gjs_context (shell_global_get ());
g_object_unref (shell_global_get ());
return ecode;
}