arc/container/bundle/rvc/95-arcinput.rules

# Copyright (c) 2023 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

KERNEL!="event*", GOTO="arcinput_end"

# Work-around for CTS compliance of R Container (not needed for P or ARCVM)

ACTION=="remove", RUN+="/bin/rm /dev/arc_input/%k", GOTO="arcinput_end"
ACTION!="add", GOTO="arcinput_end"

# Skip devices that are not part of CTS tests (b/277541769 and b/279539420)
# Sony virtual devices added by CTS did not have a space before the opening
# paren.
# This used to be a and'd set of ATTRS{name}!= checks, but in some racey cases
# during boot they would all evaluate to false, presumably because ATTRS{name}
# was unknown, which meant the test hack was activated. Hence this was changed
# to or'd == checks. See b/319553374#comment42
ATTRS{name}=="com.google.android.init.test", GOTO="arcinput_run"
ATTRS{name}=="*(Test)*", GOTO="arcinput_run"
ATTRS{name}=="*(USB Test)*", GOTO="arcinput_run"
ATTRS{name}=="*(Bluetooth Test)*", GOTO="arcinput_run"

# No matches? Do not run the input hack.
GOTO="arcinput_end"

LABEL="arcinput_run"

# Prevent Chrome from seeing the device and forwarding it to ARC via Wayland.
# That would cause ARC to see duplicated and (in the case of uhid tests) altered
# events.
RUN+="/bin/rm /dev/input/%k"

# Create in the /dev/arc_input directory the file typically in /dev/input. It
# will have the ARC "input" group and more importantly, the file will exist with
# 660 permissions *upon creation*. Otherwise, system_server will try to open the
# device after creation but before it has access.
RUN+="/bin/mkdir -p /dev/arc_input"
# [numeric 'input' gid] + [Android ugid offset] = 1004 + 655360 = 656364
RUN+="/bin/chown root:656364 /dev/arc_input"

# 02000 bit is for setgid. It makes new files inherit the gid of the directory.
# setuid has no effect for mknod, but it is OK if it is owned by root rather
# than android-root.
# If android-root must be the owner, this can be resolved by creating the file
# outside of the final directory first, but in the same devtmpfs filesystem,
# then chown'ing it and finally moving it into place.
RUN+="/bin/chmod 2755 /dev/arc_input"
RUN+="/bin/mknod -m 660 /dev/arc_input/%k c %M %m"

LABEL="arcinput_end"