/* GDBus - GLib D-Bus Library
*
* Copyright (C) 2008-2010 Red Hat, Inc.
*
* SPDX-License-Identifier: LGPL-2.1-or-later
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General
* Public License along with this library; if not, see .
*
* Author: David Zeuthen
*/
#include "config.h"
#include
#include
#include
#include
#include "gioerror.h"
#include "gdbusutils.h"
#include "gdbusaddress.h"
#include "gdbuserror.h"
#include "gioenumtypes.h"
#include "glib-private.h"
#include "gnetworkaddress.h"
#include "gsocketclient.h"
#include "giostream.h"
#include "gasyncresult.h"
#include "gtask.h"
#include "glib-private.h"
#include "gdbusprivate.h"
#include "gstdio.h"
#ifdef HAVE_UNISTD_H
#include
#endif
#include
#include
#include
#ifdef G_OS_WIN32
#include
#endif
#include "glibintl.h"
/**
* SECTION:gdbusaddress
* @title: D-Bus Addresses
* @short_description: D-Bus connection endpoints
* @include: gio/gio.h
*
* Routines for working with D-Bus addresses. A D-Bus address is a string
* like `unix:tmpdir=/tmp/my-app-name`. The exact format of addresses
* is explained in detail in the
* [D-Bus specification](http://dbus.freedesktop.org/doc/dbus-specification.html#addresses).
*
* TCP D-Bus connections are supported, but accessing them via a proxy is
* currently not supported.
*
* Since GLib 2.72, `unix:` addresses are supported on Windows with `AF_UNIX`
* support (Windows 10).
*/
static gchar *get_session_address_platform_specific (GError **error);
static gchar *get_session_address_dbus_launch (GError **error);
/* ---------------------------------------------------------------------------------------------------- */
/**
* g_dbus_is_address:
* @string: A string.
*
* Checks if @string is a
* [D-Bus address](https://dbus.freedesktop.org/doc/dbus-specification.html#addresses).
*
* This doesn't check if @string is actually supported by #GDBusServer
* or #GDBusConnection - use g_dbus_is_supported_address() to do more
* checks.
*
* Returns: %TRUE if @string is a valid D-Bus address, %FALSE otherwise.
*
* Since: 2.26
*/
gboolean
g_dbus_is_address (const gchar *string)
{
guint n;
gchar **a;
gboolean ret;
ret = FALSE;
g_return_val_if_fail (string != NULL, FALSE);
a = g_strsplit (string, ";", 0);
if (a[0] == NULL)
goto out;
for (n = 0; a[n] != NULL; n++)
{
if (!_g_dbus_address_parse_entry (a[n],
NULL,
NULL,
NULL))
goto out;
}
ret = TRUE;
out:
g_strfreev (a);
return ret;
}
static gboolean
is_valid_unix (const gchar *address_entry,
GHashTable *key_value_pairs,
GError **error)
{
gboolean ret;
GList *keys;
GList *l;
const gchar *path;
const gchar *dir;
const gchar *tmpdir;
const gchar *abstract;
ret = FALSE;
keys = NULL;
path = NULL;
dir = NULL;
tmpdir = NULL;
abstract = NULL;
keys = g_hash_table_get_keys (key_value_pairs);
for (l = keys; l != NULL; l = l->next)
{
const gchar *key = l->data;
if (g_strcmp0 (key, "path") == 0)
path = g_hash_table_lookup (key_value_pairs, key);
else if (g_strcmp0 (key, "dir") == 0)
dir = g_hash_table_lookup (key_value_pairs, key);
else if (g_strcmp0 (key, "tmpdir") == 0)
tmpdir = g_hash_table_lookup (key_value_pairs, key);
else if (g_strcmp0 (key, "abstract") == 0)
abstract = g_hash_table_lookup (key_value_pairs, key);
else if (g_strcmp0 (key, "guid") != 0)
{
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_ARGUMENT,
_("Unsupported key “%s” in address entry “%s”"),
key,
address_entry);
goto out;
}
}
/* Exactly one key must be set */
if ((path != NULL) + (dir != NULL) + (tmpdir != NULL) + (abstract != NULL) > 1)
{
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_ARGUMENT,
_("Meaningless key/value pair combination in address entry “%s”"),
address_entry);
goto out;
}
else if (path == NULL && dir == NULL && tmpdir == NULL && abstract == NULL)
{
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_ARGUMENT,
_("Address “%s” is invalid (need exactly one of path, dir, tmpdir, or abstract keys)"),
address_entry);
goto out;
}
ret = TRUE;
out:
g_list_free (keys);
return ret;
}
static gboolean
is_valid_nonce_tcp (const gchar *address_entry,
GHashTable *key_value_pairs,
GError **error)
{
gboolean ret;
GList *keys;
GList *l;
const gchar *host;
const gchar *port;
const gchar *family;
const gchar *nonce_file;
gint port_num;
gchar *endp;
ret = FALSE;
keys = NULL;
host = NULL;
port = NULL;
family = NULL;
nonce_file = NULL;
keys = g_hash_table_get_keys (key_value_pairs);
for (l = keys; l != NULL; l = l->next)
{
const gchar *key = l->data;
if (g_strcmp0 (key, "host") == 0)
host = g_hash_table_lookup (key_value_pairs, key);
else if (g_strcmp0 (key, "port") == 0)
port = g_hash_table_lookup (key_value_pairs, key);
else if (g_strcmp0 (key, "family") == 0)
family = g_hash_table_lookup (key_value_pairs, key);
else if (g_strcmp0 (key, "noncefile") == 0)
nonce_file = g_hash_table_lookup (key_value_pairs, key);
else if (g_strcmp0 (key, "guid") != 0)
{
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_ARGUMENT,
_("Unsupported key “%s” in address entry “%s”"),
key,
address_entry);
goto out;
}
}
if (port != NULL)
{
port_num = strtol (port, &endp, 10);
if ((*port == '\0' || *endp != '\0') || port_num < 0 || port_num >= 65536)
{
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_ARGUMENT,
_("Error in address “%s” — the “%s” attribute is malformed"),
address_entry, "port");
goto out;
}
}
if (family != NULL && !(g_strcmp0 (family, "ipv4") == 0 || g_strcmp0 (family, "ipv6") == 0))
{
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_ARGUMENT,
_("Error in address “%s” — the “%s” attribute is malformed"),
address_entry, "family");
goto out;
}
if (host != NULL)
{
/* TODO: validate host */
}
if (nonce_file != NULL && *nonce_file == '\0')
{
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_ARGUMENT,
_("Error in address “%s” — the “%s” attribute is malformed"),
address_entry, "noncefile");
goto out;
}
ret = TRUE;
out:
g_list_free (keys);
return ret;
}
static gboolean
is_valid_tcp (const gchar *address_entry,
GHashTable *key_value_pairs,
GError **error)
{
gboolean ret;
GList *keys;
GList *l;
const gchar *host;
const gchar *port;
const gchar *family;
gint port_num;
gchar *endp;
ret = FALSE;
keys = NULL;
host = NULL;
port = NULL;
family = NULL;
keys = g_hash_table_get_keys (key_value_pairs);
for (l = keys; l != NULL; l = l->next)
{
const gchar *key = l->data;
if (g_strcmp0 (key, "host") == 0)
host = g_hash_table_lookup (key_value_pairs, key);
else if (g_strcmp0 (key, "port") == 0)
port = g_hash_table_lookup (key_value_pairs, key);
else if (g_strcmp0 (key, "family") == 0)
family = g_hash_table_lookup (key_value_pairs, key);
else if (g_strcmp0 (key, "guid") != 0)
{
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_ARGUMENT,
_("Unsupported key “%s” in address entry “%s”"),
key,
address_entry);
goto out;
}
}
if (port != NULL)
{
port_num = strtol (port, &endp, 10);
if ((*port == '\0' || *endp != '\0') || port_num < 0 || port_num >= 65536)
{
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_ARGUMENT,
_("Error in address “%s” — the “%s” attribute is malformed"),
address_entry, "port");
goto out;
}
}
if (family != NULL && !(g_strcmp0 (family, "ipv4") == 0 || g_strcmp0 (family, "ipv6") == 0))
{
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_ARGUMENT,
_("Error in address “%s” — the “%s” attribute is malformed"),
address_entry, "family");
goto out;
}
if (host != NULL)
{
/* TODO: validate host */
}
ret= TRUE;
out:
g_list_free (keys);
return ret;
}
/**
* g_dbus_is_supported_address:
* @string: A string.
* @error: Return location for error or %NULL.
*
* Like g_dbus_is_address() but also checks if the library supports the
* transports in @string and that key/value pairs for each transport
* are valid. See the specification of the
* [D-Bus address format](https://dbus.freedesktop.org/doc/dbus-specification.html#addresses).
*
* Returns: %TRUE if @string is a valid D-Bus address that is
* supported by this library, %FALSE if @error is set.
*
* Since: 2.26
*/
gboolean
g_dbus_is_supported_address (const gchar *string,
GError **error)
{
guint n;
gchar **a;
gboolean ret;
ret = FALSE;
g_return_val_if_fail (string != NULL, FALSE);
g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
a = g_strsplit (string, ";", 0);
for (n = 0; a[n] != NULL; n++)
{
gchar *transport_name;
GHashTable *key_value_pairs;
gboolean supported;
if (!_g_dbus_address_parse_entry (a[n],
&transport_name,
&key_value_pairs,
error))
goto out;
supported = FALSE;
if (g_strcmp0 (transport_name, "unix") == 0)
supported = is_valid_unix (a[n], key_value_pairs, error);
else if (g_strcmp0 (transport_name, "tcp") == 0)
supported = is_valid_tcp (a[n], key_value_pairs, error);
else if (g_strcmp0 (transport_name, "nonce-tcp") == 0)
supported = is_valid_nonce_tcp (a[n], key_value_pairs, error);
else if (g_strcmp0 (a[n], "autolaunch:") == 0)
supported = TRUE;
else
g_set_error (error, G_IO_ERROR, G_IO_ERROR_INVALID_ARGUMENT,
_("Unknown or unsupported transport “%s” for address “%s”"),
transport_name, a[n]);
g_free (transport_name);
g_hash_table_unref (key_value_pairs);
if (!supported)
goto out;
}
ret = TRUE;
out:
g_strfreev (a);
g_assert (ret || (!ret && (error == NULL || *error != NULL)));
return ret;
}
gboolean
_g_dbus_address_parse_entry (const gchar *address_entry,
gchar **out_transport_name,
GHashTable **out_key_value_pairs,
GError **error)
{
gboolean ret;
GHashTable *key_value_pairs;
gchar *transport_name;
gchar **kv_pairs;
const gchar *s;
guint n;
ret = FALSE;
kv_pairs = NULL;
transport_name = NULL;
key_value_pairs = NULL;
s = strchr (address_entry, ':');
if (s == NULL)
{
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_ARGUMENT,
_("Address element “%s” does not contain a colon (:)"),
address_entry);
goto out;
}
else if (s == address_entry)
{
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_ARGUMENT,
_("Transport name in address element “%s” must not be empty"),
address_entry);
goto out;
}
transport_name = g_strndup (address_entry, s - address_entry);
key_value_pairs = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, g_free);
kv_pairs = g_strsplit (s + 1, ",", 0);
for (n = 0; kv_pairs[n] != NULL; n++)
{
const gchar *kv_pair = kv_pairs[n];
gchar *key;
gchar *value;
s = strchr (kv_pair, '=');
if (s == NULL)
{
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_ARGUMENT,
_("Key/Value pair %d, “%s”, in address element “%s” does not contain an equal sign"),
n,
kv_pair,
address_entry);
goto out;
}
else if (s == kv_pair)
{
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_ARGUMENT,
_("Key/Value pair %d, “%s”, in address element “%s” must not have an empty key"),
n,
kv_pair,
address_entry);
goto out;
}
key = g_uri_unescape_segment (kv_pair, s, NULL);
value = g_uri_unescape_segment (s + 1, kv_pair + strlen (kv_pair), NULL);
if (key == NULL || value == NULL)
{
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_ARGUMENT,
_("Error unescaping key or value in Key/Value pair %d, “%s”, in address element “%s”"),
n,
kv_pair,
address_entry);
g_free (key);
g_free (value);
goto out;
}
g_hash_table_insert (key_value_pairs, key, value);
}
ret = TRUE;
out:
if (ret)
{
if (out_transport_name != NULL)
*out_transport_name = g_steal_pointer (&transport_name);
if (out_key_value_pairs != NULL)
*out_key_value_pairs = g_steal_pointer (&key_value_pairs);
}
g_clear_pointer (&key_value_pairs, g_hash_table_unref);
g_free (transport_name);
g_strfreev (kv_pairs);
return ret;
}
/* ---------------------------------------------------------------------------------------------------- */
static GIOStream *
g_dbus_address_try_connect_one (const gchar *address_entry,
gchar **out_guid,
GCancellable *cancellable,
GError **error);
/* TODO: Declare an extension point called GDBusTransport (or similar)
* and move code below to extensions implementing said extension
* point. That way we can implement a D-Bus transport over X11 without
* making libgio link to libX11...
*/
static GIOStream *
g_dbus_address_connect (const gchar *address_entry,
const gchar *transport_name,
GHashTable *key_value_pairs,
GCancellable *cancellable,
GError **error)
{
GIOStream *ret;
GSocketConnectable *connectable;
const gchar *nonce_file;
connectable = NULL;
ret = NULL;
nonce_file = NULL;
if (g_strcmp0 (transport_name, "unix") == 0)
{
const gchar *path;
const gchar *abstract;
path = g_hash_table_lookup (key_value_pairs, "path");
abstract = g_hash_table_lookup (key_value_pairs, "abstract");
if ((path == NULL && abstract == NULL) || (path != NULL && abstract != NULL))
{
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_ARGUMENT,
_("Error in address “%s” — the unix transport requires exactly one of the "
"keys “path” or “abstract” to be set"),
address_entry);
}
else if (path != NULL)
{
connectable = G_SOCKET_CONNECTABLE (g_unix_socket_address_new (path));
}
else if (abstract != NULL)
{
connectable = G_SOCKET_CONNECTABLE (g_unix_socket_address_new_with_type (abstract,
-1,
G_UNIX_SOCKET_ADDRESS_ABSTRACT));
}
else
{
g_assert_not_reached ();
}
}
else if (g_strcmp0 (transport_name, "tcp") == 0 || g_strcmp0 (transport_name, "nonce-tcp") == 0)
{
const gchar *s;
const gchar *host;
glong port;
gchar *endp;
gboolean is_nonce;
is_nonce = (g_strcmp0 (transport_name, "nonce-tcp") == 0);
host = g_hash_table_lookup (key_value_pairs, "host");
if (host == NULL)
{
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_ARGUMENT,
_("Error in address “%s” — the host attribute is missing or malformed"),
address_entry);
goto out;
}
s = g_hash_table_lookup (key_value_pairs, "port");
if (s == NULL)
s = "0";
port = strtol (s, &endp, 10);
if ((*s == '\0' || *endp != '\0') || port < 0 || port >= 65536)
{
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_ARGUMENT,
_("Error in address “%s” — the port attribute is missing or malformed"),
address_entry);
goto out;
}
if (is_nonce)
{
nonce_file = g_hash_table_lookup (key_value_pairs, "noncefile");
if (nonce_file == NULL)
{
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_ARGUMENT,
_("Error in address “%s” — the noncefile attribute is missing or malformed"),
address_entry);
goto out;
}
}
/* TODO: deal with family key/value-pair */
connectable = g_network_address_new (host, port);
}
else if (g_strcmp0 (address_entry, "autolaunch:") == 0)
{
gchar *autolaunch_address;
autolaunch_address = get_session_address_dbus_launch (error);
if (autolaunch_address != NULL)
{
ret = g_dbus_address_try_connect_one (autolaunch_address, NULL, cancellable, error);
g_free (autolaunch_address);
goto out;
}
else
{
g_prefix_error (error, _("Error auto-launching: "));
}
}
else
{
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_ARGUMENT,
_("Unknown or unsupported transport “%s” for address “%s”"),
transport_name,
address_entry);
}
if (connectable != NULL)
{
GSocketClient *client;
GSocketConnection *connection;
g_assert (ret == NULL);
client = g_socket_client_new ();
/* Disable proxy support to prevent a deadlock on startup, since loading a
* proxy resolver causes the GIO modules to be loaded, and there will
* almost certainly be one of them which then tries to use GDBus.
* See: https://bugzilla.gnome.org/show_bug.cgi?id=792499 */
g_socket_client_set_enable_proxy (client, FALSE);
connection = g_socket_client_connect (client,
connectable,
cancellable,
error);
g_object_unref (connectable);
g_object_unref (client);
if (connection == NULL)
goto out;
ret = G_IO_STREAM (connection);
if (nonce_file != NULL)
{
gchar nonce_contents[16 + 1];
size_t num_bytes_read;
FILE *f;
int errsv;
/* be careful to read only 16 bytes - we also check that the file is only 16 bytes long */
f = fopen (nonce_file, "rb");
errsv = errno;
if (f == NULL)
{
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_ARGUMENT,
_("Error opening nonce file “%s”: %s"),
nonce_file,
g_strerror (errsv));
g_object_unref (ret);
ret = NULL;
goto out;
}
num_bytes_read = fread (nonce_contents,
sizeof (gchar),
16 + 1,
f);
errsv = errno;
if (num_bytes_read != 16)
{
if (num_bytes_read == 0)
{
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_ARGUMENT,
_("Error reading from nonce file “%s”: %s"),
nonce_file,
g_strerror (errsv));
}
else
{
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_INVALID_ARGUMENT,
_("Error reading from nonce file “%s”, expected 16 bytes, got %d"),
nonce_file,
(gint) num_bytes_read);
}
g_object_unref (ret);
ret = NULL;
fclose (f);
goto out;
}
fclose (f);
if (!g_output_stream_write_all (g_io_stream_get_output_stream (ret),
nonce_contents,
16,
NULL,
cancellable,
error))
{
g_prefix_error (error, _("Error writing contents of nonce file “%s” to stream:"), nonce_file);
g_object_unref (ret);
ret = NULL;
goto out;
}
}
}
out:
return ret;
}
static GIOStream *
g_dbus_address_try_connect_one (const gchar *address_entry,
gchar **out_guid,
GCancellable *cancellable,
GError **error)
{
GIOStream *ret;
GHashTable *key_value_pairs;
gchar *transport_name;
const gchar *guid;
ret = NULL;
transport_name = NULL;
key_value_pairs = NULL;
if (!_g_dbus_address_parse_entry (address_entry,
&transport_name,
&key_value_pairs,
error))
goto out;
ret = g_dbus_address_connect (address_entry,
transport_name,
key_value_pairs,
cancellable,
error);
if (ret == NULL)
goto out;
guid = g_hash_table_lookup (key_value_pairs, "guid");
if (guid != NULL && out_guid != NULL)
*out_guid = g_strdup (guid);
out:
g_free (transport_name);
if (key_value_pairs != NULL)
g_hash_table_unref (key_value_pairs);
return ret;
}
/* ---------------------------------------------------------------------------------------------------- */
typedef struct {
gchar *address;
gchar *guid;
} GetStreamData;
static void
get_stream_data_free (GetStreamData *data)
{
g_free (data->address);
g_free (data->guid);
g_free (data);
}
static void
get_stream_thread_func (GTask *task,
gpointer source_object,
gpointer task_data,
GCancellable *cancellable)
{
GetStreamData *data = task_data;
GIOStream *stream;
GError *error = NULL;
stream = g_dbus_address_get_stream_sync (data->address,
&data->guid,
cancellable,
&error);
if (stream)
g_task_return_pointer (task, stream, g_object_unref);
else
g_task_return_error (task, error);
}
/**
* g_dbus_address_get_stream:
* @address: A valid D-Bus address.
* @cancellable: (nullable): A #GCancellable or %NULL.
* @callback: A #GAsyncReadyCallback to call when the request is satisfied.
* @user_data: Data to pass to @callback.
*
* Asynchronously connects to an endpoint specified by @address and
* sets up the connection so it is in a state to run the client-side
* of the D-Bus authentication conversation. @address must be in the
* [D-Bus address format](https://dbus.freedesktop.org/doc/dbus-specification.html#addresses).
*
* When the operation is finished, @callback will be invoked. You can
* then call g_dbus_address_get_stream_finish() to get the result of
* the operation.
*
* This is an asynchronous failable function. See
* g_dbus_address_get_stream_sync() for the synchronous version.
*
* Since: 2.26
*/
void
g_dbus_address_get_stream (const gchar *address,
GCancellable *cancellable,
GAsyncReadyCallback callback,
gpointer user_data)
{
GTask *task;
GetStreamData *data;
g_return_if_fail (address != NULL);
data = g_new0 (GetStreamData, 1);
data->address = g_strdup (address);
task = g_task_new (NULL, cancellable, callback, user_data);
g_task_set_source_tag (task, g_dbus_address_get_stream);
g_task_set_task_data (task, data, (GDestroyNotify) get_stream_data_free);
g_task_run_in_thread (task, get_stream_thread_func);
g_object_unref (task);
}
/**
* g_dbus_address_get_stream_finish:
* @res: A #GAsyncResult obtained from the GAsyncReadyCallback passed to g_dbus_address_get_stream().
* @out_guid: (optional) (out) (nullable): %NULL or return location to store the GUID extracted from @address, if any.
* @error: Return location for error or %NULL.
*
* Finishes an operation started with g_dbus_address_get_stream().
*
* A server is not required to set a GUID, so @out_guid may be set to %NULL
* even on success.
*
* Returns: (transfer full): A #GIOStream or %NULL if @error is set.
*
* Since: 2.26
*/
GIOStream *
g_dbus_address_get_stream_finish (GAsyncResult *res,
gchar **out_guid,
GError **error)
{
GTask *task;
GetStreamData *data;
GIOStream *ret;
g_return_val_if_fail (g_task_is_valid (res, NULL), NULL);
g_return_val_if_fail (error == NULL || *error == NULL, NULL);
task = G_TASK (res);
ret = g_task_propagate_pointer (task, error);
if (ret != NULL && out_guid != NULL)
{
data = g_task_get_task_data (task);
*out_guid = data->guid;
data->guid = NULL;
}
return ret;
}
/**
* g_dbus_address_get_stream_sync:
* @address: A valid D-Bus address.
* @out_guid: (optional) (out) (nullable): %NULL or return location to store the GUID extracted from @address, if any.
* @cancellable: (nullable): A #GCancellable or %NULL.
* @error: Return location for error or %NULL.
*
* Synchronously connects to an endpoint specified by @address and
* sets up the connection so it is in a state to run the client-side
* of the D-Bus authentication conversation. @address must be in the
* [D-Bus address format](https://dbus.freedesktop.org/doc/dbus-specification.html#addresses).
*
* A server is not required to set a GUID, so @out_guid may be set to %NULL
* even on success.
*
* This is a synchronous failable function. See
* g_dbus_address_get_stream() for the asynchronous version.
*
* Returns: (transfer full): A #GIOStream or %NULL if @error is set.
*
* Since: 2.26
*/
GIOStream *
g_dbus_address_get_stream_sync (const gchar *address,
gchar **out_guid,
GCancellable *cancellable,
GError **error)
{
GIOStream *ret;
gchar **addr_array;
guint n;
GError *last_error;
g_return_val_if_fail (address != NULL, NULL);
g_return_val_if_fail (error == NULL || *error == NULL, NULL);
ret = NULL;
last_error = NULL;
addr_array = g_strsplit (address, ";", 0);
if (addr_array[0] == NULL)
{
last_error = g_error_new_literal (G_IO_ERROR,
G_IO_ERROR_INVALID_ARGUMENT,
_("The given address is empty"));
goto out;
}
for (n = 0; addr_array[n] != NULL; n++)
{
const gchar *addr = addr_array[n];
GError *this_error;
this_error = NULL;
ret = g_dbus_address_try_connect_one (addr,
out_guid,
cancellable,
&this_error);
if (ret != NULL)
{
goto out;
}
else
{
g_assert (this_error != NULL);
if (last_error != NULL)
g_error_free (last_error);
last_error = this_error;
}
}
out:
if (ret != NULL)
{
if (last_error != NULL)
g_error_free (last_error);
}
else
{
g_assert (last_error != NULL);
g_propagate_error (error, last_error);
}
g_strfreev (addr_array);
return ret;
}
/* ---------------------------------------------------------------------------------------------------- */
/*
* Return the address of XDG_RUNTIME_DIR/bus if it exists, belongs to
* us, and is a socket, and we are on Unix.
*/
static gchar *
get_session_address_xdg (void)
{
#ifdef G_OS_UNIX
gchar *ret = NULL;
gchar *bus;
gchar *tmp;
GStatBuf buf;
bus = g_build_filename (g_get_user_runtime_dir (), "bus", NULL);
/* if ENOENT, EPERM, etc., quietly don't use it */
if (g_stat (bus, &buf) < 0)
goto out;
/* if it isn't ours, we have incorrectly inherited someone else's
* XDG_RUNTIME_DIR; silently don't use it
*/
if (buf.st_uid != geteuid ())
goto out;
/* if it isn't a socket, silently don't use it */
if ((buf.st_mode & S_IFMT) != S_IFSOCK)
goto out;
tmp = g_dbus_address_escape_value (bus);
ret = g_strconcat ("unix:path=", tmp, NULL);
g_free (tmp);
out:
g_free (bus);
return ret;
#else
return NULL;
#endif
}
/* ---------------------------------------------------------------------------------------------------- */
#ifdef G_OS_UNIX
static gchar *
get_session_address_dbus_launch (GError **error)
{
gchar *ret;
gchar *machine_id;
gchar *command_line;
gchar *launch_stdout;
gchar *launch_stderr;
gint wait_status;
gchar *old_dbus_verbose;
gboolean restore_dbus_verbose;
ret = NULL;
machine_id = NULL;
command_line = NULL;
launch_stdout = NULL;
launch_stderr = NULL;
restore_dbus_verbose = FALSE;
old_dbus_verbose = NULL;
/* Don't run binaries as root if we're setuid. */
if (GLIB_PRIVATE_CALL (g_check_setuid) ())
{
g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,
_("Cannot spawn a message bus when AT_SECURE is set"));
goto out;
}
machine_id = _g_dbus_get_machine_id (error);
if (machine_id == NULL)
{
g_prefix_error (error, _("Cannot spawn a message bus without a machine-id: "));
goto out;
}
if (g_getenv ("DISPLAY") == NULL)
{
g_set_error (error, G_IO_ERROR, G_IO_ERROR_FAILED,
_("Cannot autolaunch D-Bus without X11 $DISPLAY"));
goto out;
}
/* We're using private libdbus facilities here. When everything
* (X11, Mac OS X, Windows) is spec'ed out correctly (not even the
* X11 property is correctly documented right now) we should
* consider using the spec instead of dbus-launch.
*
* --autolaunch=MACHINEID
* This option implies that dbus-launch should scan for a previ‐
* ously-started session and reuse the values found there. If no
* session is found, it will start a new session. The --exit-with-
* session option is implied if --autolaunch is given. This option
* is for the exclusive use of libdbus, you do not want to use it
* manually. It may change in the future.
*/
/* TODO: maybe provide a variable for where to look for the dbus-launch binary? */
command_line = g_strdup_printf ("dbus-launch --autolaunch=%s --binary-syntax --close-stderr", machine_id);
if (G_UNLIKELY (_g_dbus_debug_address ()))
{
_g_dbus_debug_print_lock ();
g_print ("GDBus-debug:Address: Running '%s' to get bus address (possibly autolaunching)\n", command_line);
old_dbus_verbose = g_strdup (g_getenv ("DBUS_VERBOSE"));
restore_dbus_verbose = TRUE;
g_setenv ("DBUS_VERBOSE", "1", TRUE);
_g_dbus_debug_print_unlock ();
}
if (!g_spawn_command_line_sync (command_line,
&launch_stdout,
&launch_stderr,
&wait_status,
error))
{
goto out;
}
if (!g_spawn_check_wait_status (wait_status, error))
{
g_prefix_error (error, _("Error spawning command line “%s”: "), command_line);
goto out;
}
/* From the dbus-launch(1) man page:
*
* --binary-syntax Write to stdout a nul-terminated bus address,
* then the bus PID as a binary integer of size sizeof(pid_t),
* then the bus X window ID as a binary integer of size
* sizeof(long). Integers are in the machine's byte order, not
* network byte order or any other canonical byte order.
*/
ret = g_strdup (launch_stdout);
out:
if (G_UNLIKELY (_g_dbus_debug_address ()))
{
gchar *s;
_g_dbus_debug_print_lock ();
g_print ("GDBus-debug:Address: dbus-launch output:");
if (launch_stdout != NULL)
{
s = _g_dbus_hexdump (launch_stdout, strlen (launch_stdout) + 1 + sizeof (pid_t) + sizeof (long), 2);
g_print ("\n%s", s);
g_free (s);
}
else
{
g_print (" (none)\n");
}
g_print ("GDBus-debug:Address: dbus-launch stderr output:");
if (launch_stderr != NULL)
g_print ("\n%s", launch_stderr);
else
g_print (" (none)\n");
_g_dbus_debug_print_unlock ();
}
g_free (machine_id);
g_free (command_line);
g_free (launch_stdout);
g_free (launch_stderr);
if (G_UNLIKELY (restore_dbus_verbose))
{
if (old_dbus_verbose != NULL)
g_setenv ("DBUS_VERBOSE", old_dbus_verbose, TRUE);
else
g_unsetenv ("DBUS_VERBOSE");
}
g_free (old_dbus_verbose);
return ret;
}
/* end of G_OS_UNIX case */
#elif defined(G_OS_WIN32)
static gchar *
get_session_address_dbus_launch (GError **error)
{
return _g_dbus_win32_get_session_address_dbus_launch (error);
}
#else /* neither G_OS_UNIX nor G_OS_WIN32 */
static gchar *
get_session_address_dbus_launch (GError **error)
{
g_set_error (error,
G_IO_ERROR,
G_IO_ERROR_FAILED,
_("Cannot determine session bus address (not implemented for this OS)"));
return NULL;
}
#endif /* neither G_OS_UNIX nor G_OS_WIN32 */
/* ---------------------------------------------------------------------------------------------------- */
static gchar *
get_session_address_platform_specific (GError **error)
{
gchar *ret;
/* Use XDG_RUNTIME_DIR/bus if it exists and is suitable. This is appropriate
* for systems using the "a session is a user-session" model described in
* ,
* and implemented in dbus >= 1.9.14 and sd-bus.
*
* On systems following the more traditional "a session is a login-session"
* model, this will fail and we'll fall through to X11 autolaunching
* (dbus-launch) below.
*/
ret = get_session_address_xdg ();
if (ret != NULL)
return ret;
/* TODO (#694472): try launchd on OS X, like
* _dbus_lookup_session_address_launchd() does, since
* 'dbus-launch --autolaunch' probably won't work there
*/
/* As a last resort, try the "autolaunch:" transport. On Unix this means
* X11 autolaunching; on Windows this means a different autolaunching
* mechanism based on shared memory.
*/
return get_session_address_dbus_launch (error);
}
/* ---------------------------------------------------------------------------------------------------- */
/**
* g_dbus_address_get_for_bus_sync:
* @bus_type: a #GBusType
* @cancellable: (nullable): a #GCancellable or %NULL
* @error: return location for error or %NULL
*
* Synchronously looks up the D-Bus address for the well-known message
* bus instance specified by @bus_type. This may involve using various
* platform specific mechanisms.
*
* The returned address will be in the
* [D-Bus address format](https://dbus.freedesktop.org/doc/dbus-specification.html#addresses).
*
* Returns: (transfer full): a valid D-Bus address string for @bus_type or
* %NULL if @error is set
*
* Since: 2.26
*/
gchar *
g_dbus_address_get_for_bus_sync (GBusType bus_type,
GCancellable *cancellable,
GError **error)
{
gboolean has_elevated_privileges = GLIB_PRIVATE_CALL (g_check_setuid) ();
gchar *ret, *s = NULL;
const gchar *starter_bus;
GError *local_error;
g_return_val_if_fail (error == NULL || *error == NULL, NULL);
ret = NULL;
local_error = NULL;
if (G_UNLIKELY (_g_dbus_debug_address ()))
{
guint n;
_g_dbus_debug_print_lock ();
s = _g_dbus_enum_to_string (G_TYPE_BUS_TYPE, bus_type);
g_print ("GDBus-debug:Address: In g_dbus_address_get_for_bus_sync() for bus type '%s'\n",
s);
g_free (s);
for (n = 0; n < 3; n++)
{
const gchar *k;
const gchar *v;
switch (n)
{
case 0: k = "DBUS_SESSION_BUS_ADDRESS"; break;
case 1: k = "DBUS_SYSTEM_BUS_ADDRESS"; break;
case 2: k = "DBUS_STARTER_BUS_TYPE"; break;
default: g_assert_not_reached ();
}
v = g_getenv (k);
g_print ("GDBus-debug:Address: env var %s", k);
if (v != NULL)
g_print ("='%s'\n", v);
else
g_print (" is not set\n");
}
_g_dbus_debug_print_unlock ();
}
/* Don’t load the addresses from the environment if running as setuid, as they
* come from an unprivileged caller. */
switch (bus_type)
{
case G_BUS_TYPE_SYSTEM:
if (has_elevated_privileges)
ret = NULL;
else
ret = g_strdup (g_getenv ("DBUS_SYSTEM_BUS_ADDRESS"));
if (ret == NULL)
{
/* While the D-Bus specification says this must be `/var/run/dbus/system_bus_socket`,
* a footnote allows it to use localstatedir:
* https://dbus.freedesktop.org/doc/dbus-specification.html#ftn.id-1.13.6.4.3.3
* or, on systems where /run is the same as /var/run, runstatedir:
* https://gitlab.freedesktop.org/dbus/dbus/-/merge_requests/209 */
ret = g_strdup ("unix:path=" GLIB_RUNSTATEDIR "/dbus/system_bus_socket");
}
break;
case G_BUS_TYPE_SESSION:
if (has_elevated_privileges)
ret = NULL;
else
ret = g_strdup (g_getenv ("DBUS_SESSION_BUS_ADDRESS"));
if (ret == NULL)
{
ret = get_session_address_platform_specific (&local_error);
}
break;
case G_BUS_TYPE_STARTER:
starter_bus = g_getenv ("DBUS_STARTER_BUS_TYPE");
if (g_strcmp0 (starter_bus, "session") == 0)
{
ret = g_dbus_address_get_for_bus_sync (G_BUS_TYPE_SESSION, cancellable, &local_error);
goto out;
}
else if (g_strcmp0 (starter_bus, "system") == 0)
{
ret = g_dbus_address_get_for_bus_sync (G_BUS_TYPE_SYSTEM, cancellable, &local_error);
goto out;
}
else
{
if (starter_bus != NULL)
{
g_set_error (&local_error,
G_IO_ERROR,
G_IO_ERROR_FAILED,
_("Cannot determine bus address from DBUS_STARTER_BUS_TYPE environment variable"
" — unknown value “%s”"),
starter_bus);
}
else
{
g_set_error_literal (&local_error,
G_IO_ERROR,
G_IO_ERROR_FAILED,
_("Cannot determine bus address because the DBUS_STARTER_BUS_TYPE environment "
"variable is not set"));
}
}
break;
default:
g_set_error (&local_error,
G_IO_ERROR,
G_IO_ERROR_FAILED,
_("Unknown bus type %d"),
bus_type);
break;
}
out:
if (G_UNLIKELY (_g_dbus_debug_address ()))
{
_g_dbus_debug_print_lock ();
s = _g_dbus_enum_to_string (G_TYPE_BUS_TYPE, bus_type);
if (ret != NULL)
{
g_print ("GDBus-debug:Address: Returning address '%s' for bus type '%s'\n",
ret, s);
}
else
{
g_print ("GDBus-debug:Address: Cannot look-up address bus type '%s': %s\n",
s, local_error ? local_error->message : "");
}
g_free (s);
_g_dbus_debug_print_unlock ();
}
if (local_error != NULL)
g_propagate_error (error, local_error);
return ret;
}
/**
* g_dbus_address_escape_value:
* @string: an unescaped string to be included in a D-Bus address
* as the value in a key-value pair
*
* Escape @string so it can appear in a D-Bus address as the value
* part of a key-value pair.
*
* For instance, if @string is `/run/bus-for-:0`,
* this function would return `/run/bus-for-%3A0`,
* which could be used in a D-Bus address like
* `unix:nonce-tcp:host=127.0.0.1,port=42,noncefile=/run/bus-for-%3A0`.
*
* Returns: (transfer full): a copy of @string with all
* non-optionally-escaped bytes escaped
*
* Since: 2.36
*/
gchar *
g_dbus_address_escape_value (const gchar *string)
{
GString *s;
gsize i;
g_return_val_if_fail (string != NULL, NULL);
/* There will often not be anything needing escaping at all. */
s = g_string_sized_new (strlen (string));
/* D-Bus address escaping is mostly the same as URI escaping... */
g_string_append_uri_escaped (s, string, "\\/", FALSE);
/* ... but '~' is an unreserved character in URIs, but a
* non-optionally-escaped character in D-Bus addresses. */
for (i = 0; i < s->len; i++)
{
if (G_UNLIKELY (s->str[i] == '~'))
{
s->str[i] = '%';
g_string_insert (s, i + 1, "7E");
i += 2;
}
}
return g_string_free (s, FALSE);
}