SandboxControllerInjector.kt
/*
* Copyright 2023 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package androidx.privacysandbox.sdkruntime.client.loader.impl
import android.os.IBinder
import androidx.privacysandbox.sdkruntime.core.SandboxedSdkCompat
import androidx.privacysandbox.sdkruntime.core.SandboxedSdkInfo
import androidx.privacysandbox.sdkruntime.core.controller.SdkSandboxControllerCompat
import java.lang.reflect.Constructor
import java.lang.reflect.InvocationHandler
import java.lang.reflect.Method
import java.lang.reflect.Proxy
/**
* Injects local implementation of [SdkSandboxControllerCompat.SandboxControllerImpl]
* to [SdkSandboxControllerCompat] loaded by SDK Classloader.
* Using [Proxy] to allow interaction between classes loaded by different classloaders.
*/
internal object SandboxControllerInjector {
/**
* Injects local implementation to SDK instance of [SdkSandboxControllerCompat].
* 1) Retrieve [SdkSandboxControllerCompat] loaded by [sdkClassLoader]
* 2) Create proxy that implements class from (1) and delegate to [controller]
* 3) Call (via reflection) [SdkSandboxControllerCompat.injectLocalImpl] with proxy from (2)
*/
fun inject(
sdkClassLoader: ClassLoader,
controller: SdkSandboxControllerCompat.SandboxControllerImpl
) {
val controllerClass = Class.forName(
SdkSandboxControllerCompat::class.java.name,
false,
sdkClassLoader
)
val controllerImplClass = Class.forName(
SdkSandboxControllerCompat.SandboxControllerImpl::class.java.name,
false,
sdkClassLoader
)
val injectMethod = controllerClass.getMethod("injectLocalImpl", controllerImplClass)
val sdkCompatBuilder = CompatSdkBuilder.createFor(sdkClassLoader)
val proxy = Proxy.newProxyInstance(
sdkClassLoader,
arrayOf(controllerImplClass),
Handler(
controller,
sdkCompatBuilder
)
)
injectMethod.invoke(null, proxy)
}
private class Handler(
private val controller: SdkSandboxControllerCompat.SandboxControllerImpl,
private val compatSdkBuilder: CompatSdkBuilder
) : InvocationHandler {
override fun invoke(proxy: Any, method: Method, args: Array<out Any?>?): Any {
return when (method.name) {
"getSandboxedSdks" -> getSandboxedSdks()
else -> {
throw UnsupportedOperationException(
"Unexpected method call object:$proxy, method: $method, args: $args"
)
}
}
}
private fun getSandboxedSdks(): List<Any> {
return controller
.getSandboxedSdks()
.map { compatSdkBuilder.createFrom(it) }
}
}
private class CompatSdkBuilder(
private val sandboxedSdkInfoConstructor: Constructor<out Any>,
private val sandboxedSdkCompatConstructor: Constructor<out Any>,
) {
/**
* Creates instance of [SandboxedSdkCompat] class loaded by SDK Classloader.
*
* @param source instance of SandboxedSdkCompat loaded by app classloader.
* @return instance of SandboxedSdkCompat loaded by SDK classloader.
*/
fun createFrom(source: SandboxedSdkCompat): Any {
val sdkInfo = createSdkInfoFrom(source.getSdkInfo())
return sandboxedSdkCompatConstructor.newInstance(source.getInterface(), sdkInfo)
}
fun createSdkInfoFrom(source: SandboxedSdkInfo?): Any? {
if (source == null) {
return null
}
return sandboxedSdkInfoConstructor.newInstance(source.name, source.version)
}
companion object {
fun createFor(classLoader: ClassLoader): CompatSdkBuilder {
val sandboxedSdkCompatClass = Class.forName(
SandboxedSdkCompat::class.java.name,
/* initialize = */ false,
classLoader
)
val sandboxedSdkInfoClass = Class.forName(
SandboxedSdkInfo::class.java.name,
/* initialize = */ false,
classLoader
)
val sandboxedSdkCompatConstructor =
sandboxedSdkCompatClass.getConstructor(
/* parameter1 */ IBinder::class.java,
/* parameter2 */ sandboxedSdkInfoClass
)
val sandboxedSdkInfoConstructor =
sandboxedSdkInfoClass.getConstructor(
/* parameter1 */ String::class.java,
/* parameter2 */ Long::class.java
)
return CompatSdkBuilder(
sandboxedSdkInfoConstructor = sandboxedSdkInfoConstructor,
sandboxedSdkCompatConstructor = sandboxedSdkCompatConstructor
)
}
}
}
}