feat(scripting): permissions

- Java Interfaces binding

common/src/main/kotlin/me/rhunk/snapenhance/common/scripting/JSModule.kt

@@ -4,11 +4,13 @@ import android.os.Handler
 import android.widget.Toast
 import me.rhunk.snapenhance.common.scripting.bindings.AbstractBinding
 import me.rhunk.snapenhance.common.scripting.bindings.BindingsContext
+import me.rhunk.snapenhance.common.scripting.impl.JavaInterfaces
 import me.rhunk.snapenhance.common.scripting.ktx.contextScope
 import me.rhunk.snapenhance.common.scripting.ktx.putFunction
 import me.rhunk.snapenhance.common.scripting.ktx.scriptable
 import me.rhunk.snapenhance.common.scripting.ktx.scriptableObject
 import me.rhunk.snapenhance.common.scripting.type.ModuleInfo
+import me.rhunk.snapenhance.common.scripting.type.Permissions
 import org.mozilla.javascript.Function
 import org.mozilla.javascript.NativeJavaObject
 import org.mozilla.javascript.ScriptableObject
@@ -49,6 +51,10 @@ class JSModule(
                 })
             })
 
+            registerBindings(
+                JavaInterfaces(),
+            )
+
             moduleObject.putFunction("setField") { args ->
                 val obj = args?.get(0) as? NativeJavaObject ?: return@putFunction Undefined.instance
                 val name = args[1].toString()
@@ -74,8 +80,12 @@ class JSModule(
 
             moduleObject.putFunction("findClass") {
                 val className = it?.get(0).toString()
+                val useModClassLoader = it?.getOrNull(1) as? Boolean ?: false
+                if (useModClassLoader) moduleInfo.ensurePermissionGranted(Permissions.UNSAFE_CLASSLOADER)
+
                 runCatching {
-                    classLoader.loadClass(className)
+                    if (useModClassLoader) this::class.java.classLoader?.loadClass(className)
+                    else classLoader.loadClass(className)
                 }.onFailure { throwable ->
                     scriptRuntime.logger.error("Failed to load class $className", throwable)
                 }.getOrNull()
@@ -83,7 +93,12 @@ class JSModule(
 
             moduleObject.putFunction("type") { args ->
                 val className = args?.get(0).toString()
-                val clazz = runCatching { classLoader.loadClass(className) }.getOrNull() ?: return@putFunction Undefined.instance
+                val useModClassLoader = args?.getOrNull(1) as? Boolean ?: false
+                if (useModClassLoader) moduleInfo.ensurePermissionGranted(Permissions.UNSAFE_CLASSLOADER)
+
+                val clazz = runCatching {
+                    if (useModClassLoader) this::class.java.classLoader?.loadClass(className) else classLoader.loadClass(className)
+                }.getOrNull() ?: return@putFunction Undefined.instance
 
                 scriptableObject("JavaClassWrapper") {
                     putFunction("newInstance") newInstance@{ args ->
@@ -116,7 +131,7 @@ class JSModule(
             }
 
             moduleObject.putFunction("logError") { args ->
-                scriptRuntime.logger.error(argsToString(arrayOf(args?.get(0))), args?.get(1) as? Throwable ?: Throwable())
+                scriptRuntime.logger.error(argsToString(arrayOf(args?.get(0))), args?.getOrNull(1) as? Throwable ?: Throwable())
                 Undefined.instance
             }
 
@@ -179,8 +194,8 @@ class JSModule(
         contextScope {
             name.split(".").also { split ->
                 val function = split.dropLast(1).fold(moduleObject) { obj, key ->
-                    obj.get(key, obj) as? ScriptableObject ?: return@contextScope
-                }.get(split.last(), moduleObject) as? Function ?: return@contextScope
+                    obj.get(key, obj) as? ScriptableObject ?: return@contextScope Unit
+                }.get(split.last(), moduleObject) as? Function ?: return@contextScope Unit
 
                 runCatching {
                     function.call(this, moduleObject, moduleObject, args)

common/src/main/kotlin/me/rhunk/snapenhance/common/scripting/impl/JavaInterfaces.kt

@@ -0,0 +1,45 @@
+package me.rhunk.snapenhance.common.scripting.impl
+
+import me.rhunk.snapenhance.common.scripting.bindings.AbstractBinding
+import me.rhunk.snapenhance.common.scripting.bindings.BindingSide
+import me.rhunk.snapenhance.common.scripting.ktx.contextScope
+import me.rhunk.snapenhance.common.scripting.ktx.putFunction
+import me.rhunk.snapenhance.common.scripting.ktx.scriptableObject
+import java.lang.reflect.Proxy
+
+class JavaInterfaces : AbstractBinding("java-interfaces", BindingSide.COMMON) {
+    override fun getObject() = scriptableObject {
+        putFunction("runnable") {
+            val function = it?.get(0) as? org.mozilla.javascript.Function ?: return@putFunction null
+            Runnable {
+                contextScope {
+                    function.call(
+                        this,
+                        this@scriptableObject,
+                        this@scriptableObject,
+                        emptyArray()
+                    )
+                }
+            }
+        }
+
+        putFunction("newProxy") { arguments ->
+            val javaInterface = arguments?.get(0) as? Class<*> ?: return@putFunction null
+            val function = arguments[1] as? org.mozilla.javascript.Function ?: return@putFunction null
+
+            Proxy.newProxyInstance(
+                javaInterface.classLoader,
+                arrayOf(javaInterface)
+            ) { instance, method, args ->
+                contextScope {
+                    function.call(
+                        this,
+                        this@scriptableObject,
+                        this@scriptableObject,
+                        arrayOf(instance, method.name, (args ?: emptyArray<Any>()).toList())
+                    )
+                }
+            }
+        }
+    }
+}

common/src/main/kotlin/me/rhunk/snapenhance/common/scripting/ktx/RhinoKtx.kt

@@ -4,12 +4,17 @@ import org.mozilla.javascript.Context
 import org.mozilla.javascript.Function
 import org.mozilla.javascript.Scriptable
 import org.mozilla.javascript.ScriptableObject
+import org.mozilla.javascript.Wrapper
 
-fun contextScope(f: Context.() -> Unit) {
+fun contextScope(f: Context.() -> Any?): Any? {
     val context = Context.enter()
     context.optimizationLevel = -1
     try {
-        context.f()
+        return context.f().let {
+            if (it is Wrapper) {
+                it.unwrap()
+            } else it
+        }
     } finally {
         Context.exit()
     }

common/src/main/kotlin/me/rhunk/snapenhance/common/scripting/type/ModuleInfo.kt

@@ -9,4 +9,20 @@ data class ModuleInfo(
     val minSnapchatVersion: Long? = null,
     val minSEVersion: Long? = null,
     val grantedPermissions: List<String>,
-)
+) {
+    override fun equals(other: Any?): Boolean {
+        if (other !is ModuleInfo) return false
+        if (other === this) return true
+        return name == other.name &&
+                version == other.version &&
+                displayName == other.displayName &&
+                description == other.description &&
+                author == other.author
+    }
+
+    fun ensurePermissionGranted(permission: Permissions) {
+        if (!grantedPermissions.contains(permission.key)) {
+            throw AssertionError("Permission $permission is not granted")
+        }
+    }
+}

common/src/main/kotlin/me/rhunk/snapenhance/common/scripting/type/Permissions.kt

@@ -0,0 +1,7 @@
+package me.rhunk.snapenhance.common.scripting.type
+
+enum class Permissions(
+    val key: String,
+) {
+    UNSAFE_CLASSLOADER("unsafe-classloader"),
+}