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#include "VirtualTouchpadService.h"
#include <inttypes.h>
#include <binder/IPCThreadState.h>
#include <binder/PermissionCache.h>
#include <binder/Status.h>
#include <cutils/log.h>
#include <linux/input.h>
#include <private/android_filesystem_config.h>
#include <utils/Errors.h>
namespace android {
namespace dvr {
namespace {
const String16 kDumpPermission("android.permission.DUMP");
const String16 kTouchPermission("android.permission.RESTRICTED_VR_ACCESS");
} // anonymous namespace
VirtualTouchpadService::~VirtualTouchpadService() {
if (client_pid_) {
client_pid_ = 0;
touchpad_->Detach();
}
}
binder::Status VirtualTouchpadService::attach() {
pid_t pid;
if (!CheckTouchPermission(&pid)) {
return binder::Status::fromStatusT(PERMISSION_DENIED);
}
if (client_pid_ == pid) {
// The same client has called attach() twice with no intervening detach().
// This indicates a problem with the client, so return an error.
// However, since the client is already attached, any touchpad actions
// it takes will still work.
ALOGE("pid=%ld attached twice", static_cast<long>(pid));
return binder::Status::fromStatusT(ALREADY_EXISTS);
}
if (client_pid_ != 0) {
// Attach while another client is attached. This can happen if the client
// dies without cleaning up after itself, so move ownership to the current
// caller. If two actual clients have connected, the problem will be
// reported when the previous client performs any touchpad action.
ALOGE("pid=%ld replaces %ld", static_cast<long>(pid),
static_cast<long>(client_pid_));
client_pid_ = pid;
return binder::Status::ok();
}
client_pid_ = pid;
if (const status_t error = touchpad_->Attach()) {
return binder::Status::fromStatusT(error);
}
return binder::Status::ok();
}
binder::Status VirtualTouchpadService::detach() {
if (!CheckPermissions()) {
return binder::Status::fromStatusT(PERMISSION_DENIED);
}
client_pid_ = 0;
if (const status_t error = touchpad_->Detach()) {
return binder::Status::fromStatusT(error);
}
return binder::Status::ok();
}
binder::Status VirtualTouchpadService::touch(int touchpad, float x, float y,
float pressure) {
if (!CheckPermissions()) {
return binder::Status::fromStatusT(PERMISSION_DENIED);
}
if (const status_t error = touchpad_->Touch(touchpad, x, y, pressure)) {
return binder::Status::fromStatusT(error);
}
return binder::Status::ok();
}
binder::Status VirtualTouchpadService::buttonState(int touchpad, int buttons) {
if (!CheckPermissions()) {
return binder::Status::fromStatusT(PERMISSION_DENIED);
}
if (const status_t error = touchpad_->ButtonState(touchpad, buttons)) {
return binder::Status::fromStatusT(error);
}
return binder::Status::ok();
}
binder::Status VirtualTouchpadService::scroll(int touchpad, float x, float y) {
if (!CheckPermissions()) {
return binder::Status::fromStatusT(PERMISSION_DENIED);
}
if (const status_t error = touchpad_->Scroll(touchpad, x, y)) {
return binder::Status::fromStatusT(error);
}
return binder::Status::ok();
}
status_t VirtualTouchpadService::dump(
int fd, const Vector<String16>& args[[gnu::unused]]) {
String8 result;
const android::IPCThreadState* ipc = android::IPCThreadState::self();
const pid_t pid = ipc->getCallingPid();
const uid_t uid = ipc->getCallingUid();
if ((uid != AID_SHELL) &&
!PermissionCache::checkPermission(kDumpPermission, pid, uid)) {
result.appendFormat("Permission denial: can't dump " LOG_TAG
" from pid=%ld, uid=%ld\n",
static_cast<long>(pid), static_cast<long>(uid));
} else {
result.appendFormat("[service]\nclient_pid = %ld\n\n",
static_cast<long>(client_pid_));
touchpad_->dumpInternal(result);
}
write(fd, result.c_str(), result.size());
return OK;
}
bool VirtualTouchpadService::CheckPermissions() {
pid_t pid;
if (!CheckTouchPermission(&pid)) {
return false;
}
if (client_pid_ != pid) {
ALOGE("pid=%ld is not owner", static_cast<long>(pid));
return false;
}
return true;
}
bool VirtualTouchpadService::CheckTouchPermission(pid_t* out_pid) {
const android::IPCThreadState* ipc = android::IPCThreadState::self();
*out_pid = ipc->getCallingPid();
const uid_t uid = ipc->getCallingUid();
const bool permission = PermissionCache::checkPermission(kTouchPermission, *out_pid, uid);
if (!permission) {
ALOGE("permission denied to pid=%ld uid=%ld", static_cast<long>(*out_pid),
static_cast<long>(uid));
}
return permission;
}
} // namespace dvr
} // namespace android
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