Files
Il2CppInspectorRedux/Il2CppInspector/Il2CppInspector.cs

278 lines
12 KiB
C#

/*
Copyright 2017-2020 Katy Coe - http://www.hearthcode.org - http://www.djkaty.com
All rights reserved.
*/
using NoisyCowStudios.Bin2Object;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
namespace Il2CppInspector
{
// Il2CppInspector ties together the binary and metadata files into a congruent API surface
public class Il2CppInspector
{
private Il2CppBinary Binary { get; }
private Metadata Metadata { get; }
// All function pointers including attribute initialization functions etc. (start => end)
public Dictionary<ulong, ulong> FunctionAddresses { get; }
// Attribute indexes (>=24.1) arranged by customAttributeStart and token
public Dictionary<int, Dictionary<uint, int>> AttributeIndicesByToken { get; }
// Shortcuts
public double Version => Metadata.Version;
public Dictionary<int, string> Strings => Metadata.Strings;
public Il2CppTypeDefinition[] TypeDefinitions => Metadata.Types;
public Il2CppAssemblyDefinition[] Assemblies => Metadata.Assemblies;
public Il2CppImageDefinition[] Images => Metadata.Images;
public Il2CppMethodDefinition[] Methods => Metadata.Methods;
public Il2CppParameterDefinition[] Params => Metadata.Params;
public Il2CppFieldDefinition[] Fields => Metadata.Fields;
public Il2CppPropertyDefinition[] Properties => Metadata.Properties;
public Il2CppEventDefinition[] Events => Metadata.Events;
public Il2CppGenericContainer[] GenericContainers => Metadata.GenericContainers;
public Il2CppGenericParameter[] GenericParameters => Metadata.GenericParameters;
public int[] GenericConstraintIndices => Metadata.GenericConstraintIndices;
public Il2CppCustomAttributeTypeRange[] AttributeTypeRanges => Metadata.AttributeTypeRanges;
public Il2CppInterfaceOffsetPair[] InterfaceOffsets => Metadata.InterfaceOffsets;
public int[] InterfaceUsageIndices => Metadata.InterfaceUsageIndices;
public int[] NestedTypeIndices => Metadata.NestedTypeIndices;
public int[] AttributeTypeIndices => Metadata.AttributeTypeIndices;
public uint[] VTableMethodIndices => Metadata.VTableMethodIndices;
public Dictionary<int, (ulong, object)> FieldDefaultValue { get; } = new Dictionary<int, (ulong, object)>();
public Dictionary<int, (ulong, object)> ParameterDefaultValue { get; } = new Dictionary<int, (ulong, object)>();
public List<long> FieldOffsets { get; }
public List<Il2CppType> TypeUsages => Binary.Types;
public Dictionary<string, Il2CppCodeGenModule> Modules => Binary.Modules;
public ulong[] CustomAttributeGenerators => Binary.CustomAttributeGenerators;
public Il2CppMethodSpec[] MethodSpecs => Binary.MethodSpecs;
// TODO: Finish all file access in the constructor and eliminate the need for this
public IFileFormatReader BinaryImage => Binary.Image;
private (ulong MetadataAddress, object Value)? getDefaultValue(int typeIndex, int dataIndex) {
// No default
if (dataIndex == -1)
return (0ul, null);
// Get pointer in binary to default value
var pValue = Metadata.Header.fieldAndParameterDefaultValueDataOffset + dataIndex;
var type = TypeUsages[typeIndex];
// Default value is null
if (pValue == 0)
return (0ul, null);
object value = null;
Metadata.Position = pValue;
switch (type.type) {
case Il2CppTypeEnum.IL2CPP_TYPE_BOOLEAN:
value = Metadata.ReadBoolean();
break;
case Il2CppTypeEnum.IL2CPP_TYPE_U1:
case Il2CppTypeEnum.IL2CPP_TYPE_I1:
value = Metadata.ReadByte();
break;
case Il2CppTypeEnum.IL2CPP_TYPE_CHAR:
// UTF-8 character assumed
value = BitConverter.ToChar(Metadata.ReadBytes(2), 0);
break;
case Il2CppTypeEnum.IL2CPP_TYPE_U2:
value = Metadata.ReadUInt16();
break;
case Il2CppTypeEnum.IL2CPP_TYPE_I2:
value = Metadata.ReadInt16();
break;
case Il2CppTypeEnum.IL2CPP_TYPE_U4:
value = Metadata.ReadUInt32();
break;
case Il2CppTypeEnum.IL2CPP_TYPE_I4:
value = Metadata.ReadInt32();
break;
case Il2CppTypeEnum.IL2CPP_TYPE_U8:
value = Metadata.ReadUInt64();
break;
case Il2CppTypeEnum.IL2CPP_TYPE_I8:
value = Metadata.ReadInt64();
break;
case Il2CppTypeEnum.IL2CPP_TYPE_R4:
value = Metadata.ReadSingle();
break;
case Il2CppTypeEnum.IL2CPP_TYPE_R8:
value = Metadata.ReadDouble();
break;
case Il2CppTypeEnum.IL2CPP_TYPE_STRING:
var uiLen = Metadata.ReadInt32();
value = Encoding.UTF8.GetString(Metadata.ReadBytes(uiLen));
break;
}
return ((ulong) pValue, value);
}
public Il2CppInspector(Il2CppBinary binary, Metadata metadata) {
// Store stream representations
Binary = binary;
Metadata = metadata;
// Get all field default values
foreach (var fdv in Metadata.FieldDefaultValues)
FieldDefaultValue.Add(fdv.fieldIndex, ((ulong,object)) getDefaultValue(fdv.typeIndex, fdv.dataIndex));
// Get all parameter default values
foreach (var pdv in Metadata.ParameterDefaultValues)
ParameterDefaultValue.Add(pdv.parameterIndex, ((ulong,object)) getDefaultValue(pdv.typeIndex, pdv.dataIndex));
// Get all field offsets
if (Binary.FieldOffsets != null) {
FieldOffsets = Binary.FieldOffsets.Select(x => (long) x).ToList();
}
// Convert pointer list into fields
else {
var offsets = new Dictionary<int, long>();
for (var i = 0; i < TypeDefinitions.Length; i++) {
var def = TypeDefinitions[i];
var pFieldOffsets = Binary.FieldOffsetPointers[i];
if (pFieldOffsets != 0) {
bool available = true;
// If the target address range is not mapped in the file, assume zeroes
try {
BinaryImage.Position = BinaryImage.MapVATR((ulong) pFieldOffsets);
}
catch (InvalidOperationException) {
available = false;
}
for (var f = 0; f < def.field_count; f++)
offsets.Add(def.fieldStart + f, available? BinaryImage.ReadUInt32() : 0);
}
}
FieldOffsets = offsets.OrderBy(x => x.Key).Select(x => x.Value).ToList();
}
// Get sorted list of function pointers from all sources
var sortedFunctionPointers = (Version <= 24.1)?
Binary.GlobalMethodPointers.ToList() :
Binary.ModuleMethodPointers.SelectMany(module => module.Value).ToList();
sortedFunctionPointers.AddRange(CustomAttributeGenerators);
sortedFunctionPointers.Sort();
sortedFunctionPointers = sortedFunctionPointers.Distinct().ToList();
// Guestimate function end addresses
FunctionAddresses = new Dictionary<ulong, ulong>(sortedFunctionPointers.Count);
for (var i = 0; i < sortedFunctionPointers.Count - 1; i++)
FunctionAddresses.Add(sortedFunctionPointers[i], sortedFunctionPointers[i + 1]);
// The last method end pointer will be incorrect but there is no way of calculating it
FunctionAddresses.Add(sortedFunctionPointers[^1], sortedFunctionPointers[^1]);
// Organize custom attribute indices
if (Version >= 24.1) {
AttributeIndicesByToken = new Dictionary<int, Dictionary<uint, int>>();
foreach (var image in Images) {
var attsByToken = new Dictionary<uint, int>();
for (int i = 0; i < image.customAttributeCount; i++) {
var index = image.customAttributeStart + i;
var token = AttributeTypeRanges[index].token;
attsByToken.Add(token, index);
}
AttributeIndicesByToken.Add(image.customAttributeStart, attsByToken);
}
}
}
public (ulong Start, ulong End)? GetMethodPointer(Il2CppCodeGenModule module, Il2CppMethodDefinition methodDef) {
// Find method pointer
if (methodDef.methodIndex < 0)
return null;
ulong start = 0;
// Global method pointer array
if (Version <= 24.1) {
start = Binary.GlobalMethodPointers[methodDef.methodIndex];
}
// Per-module method pointer array uses the bottom 24 bits of the method's metadata token
// Derived from il2cpp::vm::MetadataCache::GetMethodPointer
if (Version >= 24.2) {
var method = (methodDef.token & 0xffffff);
if (method == 0)
return null;
// In the event of an exception, the method pointer is not set in the file
// This probably means it has been optimized away by the compiler, or is an unused generic method
try {
// Remove ARM Thumb marker LSB if necessary
start = Binary.ModuleMethodPointers[module][method - 1];
}
catch (IndexOutOfRangeException) {
return null;
}
}
if (start == 0)
return null;
// Consider the end of the method to be the start of the next method (or zero)
// The last method end will be wrong but there is no way to calculate it
return (start & 0xffff_ffff_ffff_fffe, FunctionAddresses[start]);
}
public static List<Il2CppInspector> LoadFromFile(string codeFile, string metadataFile) {
// Load the metadata file
Metadata metadata;
try {
metadata = new Metadata(new MemoryStream(File.ReadAllBytes(metadataFile)));
}
catch (Exception ex) {
Console.Error.WriteLine(ex.Message);
return null;
}
Console.WriteLine("Detected metadata version " + metadata.Version);
// Load the il2cpp code file (try all available file formats)
IFileFormatReader stream = FileFormatReader.Load(codeFile);
if (stream == null) {
Console.Error.WriteLine("Unsupported executable file format");
return null;
}
// Multi-image binaries may contain more than one Il2Cpp image
var processors = new List<Il2CppInspector>();
foreach (var image in stream.Images) {
Console.WriteLine("Container format: " + image.Format);
Console.WriteLine("Container endianness: " + ((BinaryObjectReader) image).Endianness);
Console.WriteLine("Architecture word size: {0}-bit", image.Bits);
Console.WriteLine("Instruction set: " + image.Arch);
Console.WriteLine("Global offset: 0x{0:X16}", image.GlobalOffset);
// Architecture-agnostic load attempt
try {
if (Il2CppBinary.Load(image, metadata.Version) is Il2CppBinary binary) {
processors.Add(new Il2CppInspector(binary, metadata));
}
else {
Console.Error.WriteLine("Could not process IL2CPP image");
}
}
// Unknown architecture
catch (NotImplementedException ex) {
Console.Error.WriteLine(ex.Message);
}
}
return processors;
}
}
}