/* 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); }