weston/libweston/launcher-logind.c
Christopher Obbard 9e36620be7 libweston: Decouple dbus helper to public namespace
Currently the dbus helper stuff is internal only in libweston,
let's move it to being public so that custom shells may use
the helper code.

Signed-off-by: Christopher Obbard <chris.obbard@collabora.com>
2023-07-14 10:55:24 +00:00

868 lines
20 KiB
C

/*
* Copyright © 2013 David Herrmann
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial
* portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include "config.h"
#include <errno.h>
#include <fcntl.h>
#include <signal.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <systemd/sd-login.h>
#include <unistd.h>
#include <libweston/libweston.h>
#include <libweston/dbus.h>
#include "backend.h"
#include "launcher-impl.h"
#define DRM_MAJOR 226
/* major()/minor() */
#ifdef MAJOR_IN_MKDEV
#include <sys/mkdev.h>
#endif
#ifdef MAJOR_IN_SYSMACROS
#include <sys/sysmacros.h>
#endif
struct launcher_logind {
struct weston_launcher base;
struct weston_compositor *compositor;
bool sync_drm;
char *seat;
char *sid;
unsigned int vtnr;
int vt;
int kb_mode;
DBusConnection *dbus;
struct wl_event_source *dbus_ctx;
char *spath;
DBusPendingCall *pending_active;
};
static int
launcher_logind_take_device(struct launcher_logind *wl, uint32_t major,
uint32_t minor, bool *paused_out)
{
DBusMessage *m, *reply;
bool b;
int r, fd;
dbus_bool_t paused;
m = dbus_message_new_method_call("org.freedesktop.login1",
wl->spath,
"org.freedesktop.login1.Session",
"TakeDevice");
if (!m)
return -ENOMEM;
b = dbus_message_append_args(m,
DBUS_TYPE_UINT32, &major,
DBUS_TYPE_UINT32, &minor,
DBUS_TYPE_INVALID);
if (!b) {
r = -ENOMEM;
goto err_unref;
}
reply = dbus_connection_send_with_reply_and_block(wl->dbus, m,
-1, NULL);
if (!reply) {
weston_log("logind: TakeDevice on %d:%d failed.\n", major, minor);
r = -ENODEV;
goto err_unref;
}
b = dbus_message_get_args(reply, NULL,
DBUS_TYPE_UNIX_FD, &fd,
DBUS_TYPE_BOOLEAN, &paused,
DBUS_TYPE_INVALID);
if (!b) {
weston_log("logind: error parsing reply to TakeDevice.\n");
r = -ENODEV;
goto err_reply;
}
r = fd;
if (paused_out)
*paused_out = paused;
err_reply:
dbus_message_unref(reply);
err_unref:
dbus_message_unref(m);
return r;
}
static void
launcher_logind_release_device(struct launcher_logind *wl, uint32_t major,
uint32_t minor)
{
DBusMessage *m;
bool b;
m = dbus_message_new_method_call("org.freedesktop.login1",
wl->spath,
"org.freedesktop.login1.Session",
"ReleaseDevice");
if (m) {
b = dbus_message_append_args(m,
DBUS_TYPE_UINT32, &major,
DBUS_TYPE_UINT32, &minor,
DBUS_TYPE_INVALID);
if (b)
dbus_connection_send(wl->dbus, m, NULL);
dbus_message_unref(m);
}
}
static void
launcher_logind_pause_device_complete(struct launcher_logind *wl, uint32_t major,
uint32_t minor)
{
DBusMessage *m;
bool b;
m = dbus_message_new_method_call("org.freedesktop.login1",
wl->spath,
"org.freedesktop.login1.Session",
"PauseDeviceComplete");
if (m) {
b = dbus_message_append_args(m,
DBUS_TYPE_UINT32, &major,
DBUS_TYPE_UINT32, &minor,
DBUS_TYPE_INVALID);
if (b)
dbus_connection_send(wl->dbus, m, NULL);
dbus_message_unref(m);
}
}
static int
launcher_logind_open(struct weston_launcher *launcher, const char *path, int flags)
{
struct launcher_logind *wl = wl_container_of(launcher, wl, base);
struct stat st;
int fl, r, fd;
r = stat(path, &st);
if (r < 0) {
weston_log("logind: cannot stat: %s! error=%s\n", path, strerror(errno));
return -1;
}
if (!S_ISCHR(st.st_mode)) {
weston_log("logind: %s is not a character special file!\n", path);
errno = ENODEV;
return -1;
}
fd = launcher_logind_take_device(wl, major(st.st_rdev),
minor(st.st_rdev), NULL);
if (fd < 0) {
weston_log("logind: TakeDevice on %s failed, error=%s\n",
path, strerror(-fd));
errno = -fd;
return -1;
}
/* Compared to weston_launcher_open() we cannot specify the open-mode
* directly. Instead, logind passes us an fd with sane default modes.
* For DRM and evdev this means O_RDWR | O_CLOEXEC. If we want
* something else, we need to change it afterwards. We currently
* only support setting O_NONBLOCK. Changing access-modes is not
* possible so accept whatever logind passes us. */
fl = fcntl(fd, F_GETFL);
if (fl < 0) {
r = -errno;
weston_log("logind: cannot get file flags: %s\n", strerror(errno));
goto err_close;
}
if (flags & O_NONBLOCK)
fl |= O_NONBLOCK;
r = fcntl(fd, F_SETFL, fl);
if (r < 0) {
r = -errno;
weston_log("logind: cannot set O_NONBLOCK: %s\n", strerror(errno));
goto err_close;
}
return fd;
err_close:
close(fd);
launcher_logind_release_device(wl, major(st.st_rdev),
minor(st.st_rdev));
errno = -r;
return -1;
}
static void
launcher_logind_close(struct weston_launcher *launcher, int fd)
{
struct launcher_logind *wl = wl_container_of(launcher, wl, base);
struct stat st;
int r;
r = fstat(fd, &st);
close(fd);
if (r < 0) {
weston_log("logind: cannot fstat fd: %s\n", strerror(errno));
return;
}
if (!S_ISCHR(st.st_mode)) {
weston_log("logind: invalid device passed\n");
return;
}
launcher_logind_release_device(wl, major(st.st_rdev),
minor(st.st_rdev));
}
static int
launcher_logind_activate_vt(struct weston_launcher *launcher, int vt)
{
struct launcher_logind *wl = wl_container_of(launcher, wl, base);
DBusMessage *m;
bool b;
int r;
m = dbus_message_new_method_call("org.freedesktop.login1",
"/org/freedesktop/login1/seat/self",
"org.freedesktop.login1.Seat",
"SwitchTo");
if (!m)
return -ENOMEM;
b = dbus_message_append_args(m,
DBUS_TYPE_UINT32, &vt,
DBUS_TYPE_INVALID);
if (!b) {
r = -ENOMEM;
goto err_unref;
}
dbus_connection_send(wl->dbus, m, NULL);
r = 0;
err_unref:
dbus_message_unref(m);
return r;
}
static void
launcher_logind_set_active(struct launcher_logind *wl, bool active)
{
if (wl->compositor->session_active == active)
return;
wl->compositor->session_active = active;
wl_signal_emit(&wl->compositor->session_signal,
wl->compositor);
}
static void
parse_active(struct launcher_logind *wl, DBusMessage *m, DBusMessageIter *iter)
{
DBusMessageIter sub;
dbus_bool_t b;
if (dbus_message_iter_get_arg_type(iter) != DBUS_TYPE_VARIANT)
return;
dbus_message_iter_recurse(iter, &sub);
if (dbus_message_iter_get_arg_type(&sub) != DBUS_TYPE_BOOLEAN)
return;
dbus_message_iter_get_basic(&sub, &b);
/* If the backend requested DRM master-device synchronization, we only
* wake-up the compositor once the master-device is up and running. For
* other backends, we immediately forward the Active-change event. */
if (!wl->sync_drm || !b)
launcher_logind_set_active(wl, b);
}
static void
get_active_cb(DBusPendingCall *pending, void *data)
{
struct launcher_logind *wl = data;
DBusMessageIter iter;
DBusMessage *m;
int type;
dbus_pending_call_unref(wl->pending_active);
wl->pending_active = NULL;
m = dbus_pending_call_steal_reply(pending);
if (!m)
return;
type = dbus_message_get_type(m);
if (type == DBUS_MESSAGE_TYPE_METHOD_RETURN &&
dbus_message_iter_init(m, &iter))
parse_active(wl, m, &iter);
dbus_message_unref(m);
}
static void
launcher_logind_get_active(struct launcher_logind *wl)
{
DBusPendingCall *pending;
DBusMessage *m;
bool b;
const char *iface, *name;
m = dbus_message_new_method_call("org.freedesktop.login1",
wl->spath,
"org.freedesktop.DBus.Properties",
"Get");
if (!m)
return;
iface = "org.freedesktop.login1.Session";
name = "Active";
b = dbus_message_append_args(m,
DBUS_TYPE_STRING, &iface,
DBUS_TYPE_STRING, &name,
DBUS_TYPE_INVALID);
if (!b)
goto err_unref;
b = dbus_connection_send_with_reply(wl->dbus, m, &pending, -1);
if (!b)
goto err_unref;
b = dbus_pending_call_set_notify(pending, get_active_cb, wl, NULL);
if (!b) {
dbus_pending_call_cancel(pending);
dbus_pending_call_unref(pending);
goto err_unref;
}
if (wl->pending_active) {
dbus_pending_call_cancel(wl->pending_active);
dbus_pending_call_unref(wl->pending_active);
}
wl->pending_active = pending;
return;
err_unref:
dbus_message_unref(m);
}
static void
disconnected_dbus(struct launcher_logind *wl)
{
weston_log("logind: dbus connection lost, exiting..\n");
exit(-1);
}
static void
session_removed(struct launcher_logind *wl, DBusMessage *m)
{
const char *name, *obj;
bool r;
r = dbus_message_get_args(m, NULL,
DBUS_TYPE_STRING, &name,
DBUS_TYPE_OBJECT_PATH, &obj,
DBUS_TYPE_INVALID);
if (!r) {
weston_log("logind: cannot parse SessionRemoved dbus signal\n");
return;
}
if (!strcmp(name, wl->sid)) {
weston_log("logind: our session got closed, exiting..\n");
exit(-1);
}
}
static void
property_changed(struct launcher_logind *wl, DBusMessage *m)
{
DBusMessageIter iter, sub, entry;
const char *interface, *name;
if (!dbus_message_iter_init(m, &iter) ||
dbus_message_iter_get_arg_type(&iter) != DBUS_TYPE_STRING)
goto error;
dbus_message_iter_get_basic(&iter, &interface);
if (!dbus_message_iter_next(&iter) ||
dbus_message_iter_get_arg_type(&iter) != DBUS_TYPE_ARRAY)
goto error;
dbus_message_iter_recurse(&iter, &sub);
while (dbus_message_iter_get_arg_type(&sub) == DBUS_TYPE_DICT_ENTRY) {
dbus_message_iter_recurse(&sub, &entry);
if (dbus_message_iter_get_arg_type(&entry) != DBUS_TYPE_STRING)
goto error;
dbus_message_iter_get_basic(&entry, &name);
if (!dbus_message_iter_next(&entry))
goto error;
if (!strcmp(name, "Active")) {
parse_active(wl, m, &entry);
return;
}
dbus_message_iter_next(&sub);
}
if (!dbus_message_iter_next(&iter) ||
dbus_message_iter_get_arg_type(&iter) != DBUS_TYPE_ARRAY)
goto error;
dbus_message_iter_recurse(&iter, &sub);
while (dbus_message_iter_get_arg_type(&sub) == DBUS_TYPE_STRING) {
dbus_message_iter_get_basic(&sub, &name);
if (!strcmp(name, "Active")) {
launcher_logind_get_active(wl);
return;
}
dbus_message_iter_next(&sub);
}
return;
error:
weston_log("logind: cannot parse PropertiesChanged dbus signal\n");
}
static void
device_paused(struct launcher_logind *wl, DBusMessage *m)
{
bool r;
const char *type;
uint32_t major, minor;
r = dbus_message_get_args(m, NULL,
DBUS_TYPE_UINT32, &major,
DBUS_TYPE_UINT32, &minor,
DBUS_TYPE_STRING, &type,
DBUS_TYPE_INVALID);
if (!r) {
weston_log("logind: cannot parse PauseDevice dbus signal\n");
return;
}
/* "pause" means synchronous pausing. Acknowledge it unconditionally
* as we support asynchronous device shutdowns, anyway.
* "force" means asynchronous pausing.
* "gone" means the device is gone. We handle it the same as "force" as
* a following udev event will be caught, too.
*
* If it's our main DRM device, tell the compositor to go asleep. */
if (!strcmp(type, "pause"))
launcher_logind_pause_device_complete(wl, major, minor);
if (wl->sync_drm && wl->compositor->backend->device_changed)
wl->compositor->backend->device_changed(wl->compositor->backend,
makedev(major,minor),
false);
}
static void
device_resumed(struct launcher_logind *wl, DBusMessage *m)
{
bool r;
uint32_t major, minor;
r = dbus_message_get_args(m, NULL,
DBUS_TYPE_UINT32, &major,
DBUS_TYPE_UINT32, &minor,
DBUS_TYPE_INVALID);
if (!r) {
weston_log("logind: cannot parse ResumeDevice dbus signal\n");
return;
}
/* DeviceResumed messages provide us a new file-descriptor for
* resumed devices. For DRM devices it's the same as before, for evdev
* devices it's a new open-file. As we reopen evdev devices, anyway,
* there is no need for us to handle this event for evdev. For DRM, we
* notify the compositor to wake up. */
if (wl->sync_drm && wl->compositor->backend->device_changed)
wl->compositor->backend->device_changed(wl->compositor->backend,
makedev(major,minor),
true);
}
static DBusHandlerResult
filter_dbus(DBusConnection *c, DBusMessage *m, void *data)
{
struct launcher_logind *wl = data;
if (dbus_message_is_signal(m, DBUS_INTERFACE_LOCAL, "Disconnected")) {
disconnected_dbus(wl);
} else if (dbus_message_is_signal(m, "org.freedesktop.login1.Manager",
"SessionRemoved")) {
session_removed(wl, m);
} else if (dbus_message_is_signal(m, "org.freedesktop.DBus.Properties",
"PropertiesChanged")) {
property_changed(wl, m);
} else if (dbus_message_is_signal(m, "org.freedesktop.login1.Session",
"PauseDevice")) {
device_paused(wl, m);
} else if (dbus_message_is_signal(m, "org.freedesktop.login1.Session",
"ResumeDevice")) {
device_resumed(wl, m);
}
return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
}
static int
launcher_logind_setup_dbus(struct launcher_logind *wl)
{
bool b;
int r;
r = asprintf(&wl->spath, "/org/freedesktop/login1/session/%s",
wl->sid);
if (r < 0)
return -ENOMEM;
b = dbus_connection_add_filter(wl->dbus, filter_dbus, wl, NULL);
if (!b) {
weston_log("logind: cannot add dbus filter\n");
r = -ENOMEM;
goto err_spath;
}
r = weston_dbus_add_match_signal(wl->dbus,
"org.freedesktop.login1",
"org.freedesktop.login1.Manager",
"SessionRemoved",
"/org/freedesktop/login1");
if (r < 0) {
weston_log("logind: cannot add dbus match\n");
goto err_spath;
}
r = weston_dbus_add_match_signal(wl->dbus,
"org.freedesktop.login1",
"org.freedesktop.login1.Session",
"PauseDevice",
wl->spath);
if (r < 0) {
weston_log("logind: cannot add dbus match\n");
goto err_spath;
}
r = weston_dbus_add_match_signal(wl->dbus,
"org.freedesktop.login1",
"org.freedesktop.login1.Session",
"ResumeDevice",
wl->spath);
if (r < 0) {
weston_log("logind: cannot add dbus match\n");
goto err_spath;
}
r = weston_dbus_add_match_signal(wl->dbus,
"org.freedesktop.login1",
"org.freedesktop.DBus.Properties",
"PropertiesChanged",
wl->spath);
if (r < 0) {
weston_log("logind: cannot add dbus match\n");
goto err_spath;
}
return 0;
err_spath:
/* don't remove any dbus-match as the connection is closed, anyway */
free(wl->spath);
return r;
}
static void
launcher_logind_destroy_dbus(struct launcher_logind *wl)
{
/* don't remove any dbus-match as the connection is closed, anyway */
free(wl->spath);
}
static int
launcher_logind_take_control(struct launcher_logind *wl)
{
DBusError err;
DBusMessage *m, *reply;
dbus_bool_t force;
bool b;
int r;
dbus_error_init(&err);
m = dbus_message_new_method_call("org.freedesktop.login1",
wl->spath,
"org.freedesktop.login1.Session",
"TakeControl");
if (!m)
return -ENOMEM;
force = false;
b = dbus_message_append_args(m,
DBUS_TYPE_BOOLEAN, &force,
DBUS_TYPE_INVALID);
if (!b) {
r = -ENOMEM;
goto err_unref;
}
reply = dbus_connection_send_with_reply_and_block(wl->dbus,
m, -1, &err);
if (!reply) {
if (dbus_error_has_name(&err, DBUS_ERROR_UNKNOWN_METHOD))
weston_log("logind: old systemd version detected\n");
else
weston_log("logind: cannot take control over session %s\n", wl->sid);
dbus_error_free(&err);
r = -EIO;
goto err_unref;
}
dbus_message_unref(reply);
dbus_message_unref(m);
return 0;
err_unref:
dbus_message_unref(m);
return r;
}
static void
launcher_logind_release_control(struct launcher_logind *wl)
{
DBusMessage *m;
m = dbus_message_new_method_call("org.freedesktop.login1",
wl->spath,
"org.freedesktop.login1.Session",
"ReleaseControl");
if (m) {
dbus_connection_send(wl->dbus, m, NULL);
dbus_message_unref(m);
}
}
static int
launcher_logind_activate(struct launcher_logind *wl)
{
DBusMessage *m;
m = dbus_message_new_method_call("org.freedesktop.login1",
wl->spath,
"org.freedesktop.login1.Session",
"Activate");
if (!m)
return -ENOMEM;
dbus_connection_send(wl->dbus, m, NULL);
return 0;
}
static int
launcher_logind_get_session(char **session)
{
int r;
r = sd_pid_get_session(getpid(), session);
if (r < 0) {
if (r != -ENODATA) {
weston_log("logind: not running in a systemd session: %d\n", r);
return r;
}
} else {
return r;
}
/* When not inside a systemd session look if there is a suitable one */
r = sd_uid_get_display(getuid(), session);
if (r < 0)
weston_log("logind: cannot find systemd session for uid: %d %d\n", getuid(), r);
return r;
}
static int
launcher_logind_connect(struct weston_launcher **out, struct weston_compositor *compositor,
const char *seat_id, bool sync_drm)
{
struct launcher_logind *wl;
struct wl_event_loop *loop;
char *t;
int r;
wl = zalloc(sizeof(*wl));
if (wl == NULL) {
r = -ENOMEM;
goto err_out;
}
wl->base.iface = &launcher_logind_iface;
wl->compositor = compositor;
wl->sync_drm = sync_drm;
wl->seat = strdup(seat_id);
if (!wl->seat) {
r = -ENOMEM;
goto err_wl;
}
r = launcher_logind_get_session(&wl->sid);
if (r < 0)
goto err_seat;
t = NULL;
r = sd_session_get_seat(wl->sid, &t);
if (r < 0) {
weston_log("logind: failed to get session seat\n");
free(t);
goto err_session;
} else if (strcmp(seat_id, t)) {
weston_log("logind: weston's seat '%s' differs from session-seat '%s'\n",
seat_id, t);
r = -EINVAL;
free(t);
goto err_session;
}
r = sd_seat_can_tty(t);
free(t);
if (r > 0) {
r = sd_session_get_vt(wl->sid, &wl->vtnr);
if (r < 0) {
weston_log("logind: session not running on a VT\n");
goto err_session;
}
} else if (r < 0) {
weston_log("logind: could not determine if seat %s has ttys or not", t);
r = -EINVAL;
goto err_session;
}
loop = wl_display_get_event_loop(compositor->wl_display);
r = weston_dbus_open(loop, DBUS_BUS_SYSTEM, &wl->dbus, &wl->dbus_ctx);
if (r < 0) {
weston_log("logind: cannot connect to system dbus\n");
goto err_session;
}
r = launcher_logind_setup_dbus(wl);
if (r < 0)
goto err_dbus;
r = launcher_logind_take_control(wl);
if (r < 0)
goto err_dbus_cleanup;
r = launcher_logind_activate(wl);
if (r < 0)
goto err_dbus_cleanup;
weston_log("logind: session control granted\n");
* (struct launcher_logind **) out = wl;
return 0;
err_dbus_cleanup:
launcher_logind_destroy_dbus(wl);
err_dbus:
weston_dbus_close(wl->dbus, wl->dbus_ctx);
err_session:
free(wl->sid);
err_seat:
free(wl->seat);
err_wl:
free(wl);
err_out:
weston_log("logind: cannot setup systemd-logind helper error: (%s), using legacy fallback\n",
strerror(-r));
errno = -r;
return -1;
}
static void
launcher_logind_destroy(struct weston_launcher *launcher)
{
struct launcher_logind *wl = wl_container_of(launcher, wl, base);
if (wl->pending_active) {
dbus_pending_call_cancel(wl->pending_active);
dbus_pending_call_unref(wl->pending_active);
}
launcher_logind_release_control(wl);
launcher_logind_destroy_dbus(wl);
weston_dbus_close(wl->dbus, wl->dbus_ctx);
free(wl->sid);
free(wl->seat);
free(wl);
}
static int
launcher_logind_get_vt(struct weston_launcher *launcher)
{
struct launcher_logind *wl = wl_container_of(launcher, wl, base);
return wl->vtnr;
}
const struct launcher_interface launcher_logind_iface = {
.name = "logind",
.connect = launcher_logind_connect,
.destroy = launcher_logind_destroy,
.open = launcher_logind_open,
.close = launcher_logind_close,
.activate_vt = launcher_logind_activate_vt,
.get_vt = launcher_logind_get_vt,
};