Add: MethodResolver, PatternScanner, SignatureLoader & Cache

build.gradle.kts

@@ -12,12 +12,12 @@ repositories {
 
 dependencies {
     implementation(kotlin("stdlib"))
-    testImplementation(kotlin("test"))
-
     implementation("org.ow2.asm:asm:9.2")
     implementation("org.ow2.asm:asm-util:9.2")
     implementation("org.ow2.asm:asm-tree:9.2")
     implementation("org.ow2.asm:asm-commons:9.2")
+    implementation("com.google.code.gson:gson:2.9.0")
+    testImplementation(kotlin("test"))
 }
 
 tasks.test {

settings.gradle.kts

@@ -1,2 +1,2 @@
-rootProject.name = "patcher"
+rootProject.name = "ReVanced Patcher"
 

src/main/kotlin/net/revanced/patcher/MethodResolver.kt

@@ -0,0 +1,38 @@
+package net.revanced.patcher
+
+import net.revanced.patcher.signature.model.Signature
+import org.objectweb.asm.tree.InsnList
+import org.objectweb.asm.tree.MethodNode
+
+internal class MethodResolver(private val targetMethods: List<MethodNode>, private val signatures: List<Signature>)  {
+    fun resolve(): MutableMap<String, MethodNode> {
+        val methods = mutableMapOf<String, MethodNode>()
+
+        for (signature in signatures) {
+            val method = targetMethods.firstOrNull { method ->
+                method.access == signature.accessors &&
+                        signature.parameters.all { parameter ->
+                            method.parameters.any { methodParameter ->
+                                true //TODO check for parameter element type
+                            }
+                        } && method.instructions.scanFor(signature.opcodes)
+            } ?: continue
+            methods[signature.name] = method
+        }
+
+        return methods
+    }
+}
+
+//TODO: implement returning the index of the needle in the hay
+private fun InsnList.scanFor(pattern: Array<Int>): Boolean {
+    for (i in 0 until this.size()) {
+        var occurrence = 0
+        while (i + occurrence < this.size()) {
+            if (this.get(i + occurrence).opcode != pattern.get(occurrence)) break
+            if (++occurrence >= pattern.size) return true
+        }
+    }
+
+    return false
+}

src/main/kotlin/net/revanced/patcher/Patcher.kt

@@ -1,48 +1,55 @@
 package net.revanced.patcher
 
+import net.revanced.patcher.cache.Cache
 import net.revanced.patcher.patch.Patch
-import net.revanced.patcher.signature.Signature
-import net.revanced.patcher.store.ASMStore
-import net.revanced.patcher.store.PatchStore
-import net.revanced.patcher.util.Jar2ASM
-import java.io.InputStream
-import java.lang.IllegalStateException
+import net.revanced.patcher.signature.model.Signature
+import org.objectweb.asm.ClassReader
+import org.objectweb.asm.tree.ClassNode
+import org.objectweb.asm.tree.MethodNode
+import java.io.File
+import java.util.jar.JarFile
 
-/**
- * The patcher. (docs WIP)
- *
- * @param input the input stream to read from, must be a JAR file (for now)
- */
-class Patcher(
-    input: InputStream,
-    private val signatures: Array<Signature>,
-    patches: Array<Patch>,
+class Patcher private constructor(
+    file: File,
+    signatures: List<Signature>
 ) {
-    private val patchStore = PatchStore()
-    private val asmStore = ASMStore()
-
-    private val scanned = false
+    val cache = Cache()
+    private val patches: MutableList<Patch> = mutableListOf()
 
     init {
-        patchStore.addPatches(*patches)
-        loadJar(input)
+        // collecting all methods here
+        val targetMethods: MutableList<MethodNode> = mutableListOf()
+
+        val jarFile = JarFile(file)
+            jarFile.stream().forEach { jarEntry ->
+            jarFile.getInputStream(jarEntry).use { jis ->
+                if (jarEntry.name.endsWith(".class")) {
+                    val classNode = ClassNode()
+                    ClassReader(jis.readAllBytes()).accept(classNode, ClassReader.EXPAND_FRAMES)
+                    targetMethods.addAll(classNode.methods)
+                }
+            }
+        }
+
+        // reducing to required methods via signatures
+        cache.Methods = MethodResolver(targetMethods, signatures).resolve()
+
     }
 
-    fun scan() {
-        val methods = PatternScanner(signatures).resolve()
+    companion object {
+        fun loadFromFile(file: String, signatures: List<Signature>): Patcher = Patcher(File(file), signatures)
     }
 
-    fun patch(): String? {
-        if (!scanned) throw IllegalStateException("Pattern scanner not yet ran")
-        for ((_, patch) in patchStore.patches) {
+    fun addPatches(vararg patches: Patch) {
+        this.patches.addAll(patches)
+    }
+
+    fun executePatches(): String? {
+        for (patch in patches) {
             val result = patch.execute()
             if (result.isSuccess()) continue
             return result.error()!!.errorMessage()
         }
         return null
     }
-
-    private fun loadJar(input: InputStream) {
-        asmStore.classes.putAll(Jar2ASM.jar2asm(input))
-    }
 }

src/main/kotlin/net/revanced/patcher/PatternScanner.kt

@@ -1,9 +0,0 @@
-package net.revanced.patcher
-
-import net.revanced.patcher.signature.Signature
-
-class PatternScanner(signatures: Array<Signature>) {
-    fun resolve() {
-        TODO("Not yet implemented")
-    }
-}

src/main/kotlin/net/revanced/patcher/cache/Cache.kt

@@ -0,0 +1,7 @@
+package net.revanced.patcher.cache
+
+import org.objectweb.asm.tree.MethodNode
+
+data class Cache(
+    var Methods: Map<String, MethodNode> = mutableMapOf()
+)

src/main/kotlin/net/revanced/patcher/patch/Patch.kt

@@ -1,6 +1,6 @@
 package net.revanced.patcher.patch
 
-class Patch(val name: String, val fn: () -> PatchResult) {
+class Patch(val patchName: String, val fn: () -> PatchResult) {
     fun execute(): PatchResult {
         return fn()
     }

src/main/kotlin/net/revanced/patcher/signature/Signature.kt

@@ -1,48 +0,0 @@
-package net.revanced.patcher.signature
-
-import org.objectweb.asm.Type
-
-/**
- * An ASM signature list for the Patcher.
- *
- * @param name The name of the method.
- * Do not use the actual method name, instead try to guess what the method name originally was.
- * If you are unable to guess a method name, doing something like "patch-name-1" is fine too.
- * For example: "override-codec-1".
- * This method name will be used to find the corresponding patch.
- * @param returns The return type/signature of the method.
- * @param accessors The accessors of the method.
- * @param parameters The parameter types/signatures of the method.
- * @param opcodes The opcode pattern of the method, used to find the method by signature scanning.
- */
-data class Signature(
-    val name: String,
-    val returns: Type,
-    val accessors: Array<Int>,
-    val parameters: Array<Type>,
-    val opcodes: Array<Int>
-) {
-    override fun equals(other: Any?): Boolean {
-        if (this === other) return true
-        if (javaClass != other?.javaClass) return false
-
-        other as Signature
-
-        if (name != other.name) return false
-        if (returns != other.returns) return false
-        if (!accessors.contentEquals(other.accessors)) return false
-        if (!parameters.contentEquals(other.parameters)) return false
-        if (!opcodes.contentEquals(other.opcodes)) return false
-
-        return true
-    }
-
-    override fun hashCode(): Int {
-        var result = name.hashCode()
-        result = 31 * result + returns.hashCode()
-        result = 31 * result + accessors.contentHashCode()
-        result = 31 * result + parameters.contentHashCode()
-        result = 31 * result + opcodes.contentHashCode()
-        return result
-    }
-}

src/main/kotlin/net/revanced/patcher/signature/SignatureLoader.kt

@@ -0,0 +1,12 @@
+package net.revanced.patcher.signature
+
+import com.google.gson.Gson
+import net.revanced.patcher.signature.model.Signature
+
+object SignatureLoader {
+    private val gson = Gson()
+
+    fun LoadFromJson(json: String): Array<Signature> {
+        return gson.fromJson(json, Array<Signature>::class.java)
+    }
+}

src/main/kotlin/net/revanced/patcher/signature/model/Signature.kt

@@ -0,0 +1,25 @@
+package net.revanced.patcher.signature.model
+
+import org.objectweb.asm.Type
+import org.objectweb.asm.tree.ParameterNode
+
+/**
+ * An ASM signature list for the Patcher.
+ *
+ * @param name The name of the method.
+ * Do not use the actual method name, instead try to guess what the method name originally was.
+ * If you are unable to guess a method name, doing something like "patch-name-1" is fine too.
+ * For example: "override-codec-1".
+ * This method name will be used to find the corresponding patch.
+ * @param returns The return type/signature of the method.
+ * @param accessors The accessors of the method.
+ * @param parameters The parameter types/signatures of the method.
+ * @param opcodes The opcode pattern of the method, used to find the method by signature scanning.
+ */
+data class Signature(
+    val name: String,
+    val returns: Type,
+    @Suppress("ArrayInDataClass") val accessors: Int,
+    @Suppress("ArrayInDataClass") val parameters: Array<ParameterNode>,
+    @Suppress("ArrayInDataClass") val opcodes: Array<Int>
+)

src/main/kotlin/net/revanced/patcher/store/ASMStore.kt

@@ -1,9 +0,0 @@
-package net.revanced.patcher.store
-
-import org.objectweb.asm.tree.ClassNode
-import org.objectweb.asm.tree.MethodNode
-
-class ASMStore {
-    val classes: MutableMap<String, ClassNode> = mutableMapOf()
-    val methods: MutableMap<String, MethodNode> = mutableMapOf()
-}

src/main/kotlin/net/revanced/patcher/store/PatchStore.kt

@@ -1,13 +0,0 @@
-package net.revanced.patcher.store
-
-import net.revanced.patcher.patch.Patch
-
-class PatchStore {
-    val patches: MutableMap<String, Patch> = mutableMapOf()
-
-    fun addPatches(vararg patches: Patch) {
-        for (patch in patches) {
-            this.patches[patch.name] = patch
-        }
-    }
-}

src/main/kotlin/net/revanced/patcher/util/Jar2ASM.kt

@@ -1,18 +0,0 @@
-package net.revanced.patcher.util
-
-import org.objectweb.asm.tree.ClassNode
-import java.io.InputStream
-import java.util.jar.JarInputStream
-
-object Jar2ASM {
-    fun jar2asm(input: InputStream): Map<String, ClassNode> {
-        return buildMap {
-            val jar = JarInputStream(input)
-            var e = jar.nextJarEntry
-            while (e != null) {
-                TODO("Read jar file ...")
-                e = jar.nextJarEntry
-            }
-        }
-    }
-}

src/main/kotlin/net/revanced/patcher/util/PatternScanner.kt

@@ -0,0 +1,11 @@
+package net.revanced.patcher.util
+
+import org.objectweb.asm.tree.ClassNode
+
+class PatternScanner (private val classes: Array<ClassNode>) {
+    companion object {
+        fun scan(){
+
+        }
+    }
+}

src/test/kotlin/net/revanced/patcher/PatcherTest.kt

@@ -2,14 +2,29 @@ package net.revanced.patcher
 
 import net.revanced.patcher.patch.Patch
 import net.revanced.patcher.patch.PatchResultError
+import net.revanced.patcher.patch.PatchResultSuccess
+import net.revanced.patcher.signature.SignatureLoader
 import org.junit.jupiter.api.Test
 
 internal class PatcherTest {
     @Test
     fun template() {
-        val adRemoverPatch = Patch {
+        val patcher = Patcher.loadFromFile(
+            "some.apk",
+            SignatureLoader.LoadFromJson("signatures.json").toMutableList()
+        )
 
-            PatchResultError("")
-        }
+        val patches = mutableListOf(
+            Patch ("RemoveVideoAds") {
+                val videoAdShowMethodInstr = patcher.cache.Methods["SomeMethod"]?.instructions
+                PatchResultSuccess()
+            },
+            Patch ("TweakLayout")  {
+                val layoutMethod = patcher.cache.Methods["SomeMethod2"]
+                PatchResultError("Failed")
+            }
+        )
+
+        patcher.executePatches()
     }
 }