Add 64-bit Mach-O support

Il2CppInspector/FileFormatReaders/FormatLayouts/MachO.cs

@@ -30,7 +30,7 @@ namespace Il2CppInspector
         CPU_TYPE_ARM64 = 0x01000000 + CPU_TYPE_ARM
     }
 
-    internal class MachOHeader
+    internal class MachOHeader<TWord> where TWord : struct
     {
         public uint Magic;
         public uint CPUType;
@@ -38,8 +38,7 @@ namespace Il2CppInspector
         public uint FileType;
         public uint NumCommands;
         public uint SizeOfCommands;
-        public uint Flags;
+        public TWord Flags;
-        // 64-bit header has an extra 32-bit Reserved field
     }
 
     internal class MachOLoadCommand
@@ -48,69 +47,36 @@ namespace Il2CppInspector
         public uint Size;
     }
 
-    internal class MachOSegmentCommand
+    internal class MachOSegmentCommand<TWord> where TWord : struct
     {
         // MachOLoadCommand
         [String(FixedSize = 16)]
         public string Name;
-        public uint VirtualAddress;
+        public TWord VirtualAddress;
-        public uint VirtualSize;
+        public TWord VirtualSize;
-        public uint ImageOffset;
+        public TWord ImageOffset;
-        public uint ImageSize;
+        public TWord ImageSize;
         public uint VMMaxProt;
         public uint VMInitProt;
         public uint NumSections;
         public uint Flags;
     }
 
-    internal class MachOSegmentCommand64
+    internal class MachOSection<TWord> where TWord : struct
-    {
-        // MachOLoadCommand
-        [String(FixedSize = 16)]
-        public string Name;
-        public ulong VirtualAddress;
-        public ulong VirtualSize;
-        public ulong ImageOffset;
-        public ulong ImageSize;
-        public uint VMMaxProt;
-        public uint VMInitProt;
-        public uint NumSections;
-        public uint Flags;
-    }
-
-    internal class MachOSection
     {
         [String(FixedSize = 16)]
         public string Name;
         [String(FixedSize = 16)]
         public string SegmentName;
-        public uint Address;
+        public TWord Address;
-        public uint Size;
+        public TWord Size;
         public uint ImageOffset;
         public uint Align;
         public uint ImageRelocOffset;
         public uint NumRelocEntries;
         public uint Flags;
         public uint Reserved1;
-        public uint Reserved2;
+        public TWord Reserved2;
-    }
-
-    internal class MachOSection64
-    {
-        [String(FixedSize = 16)]
-        public string Name;
-        [String(FixedSize = 16)]
-        public string SegmentName;
-        public ulong Address;
-        public ulong Size;
-        public uint ImageOffset;
-        public uint Align;
-        public uint ImageRelocOffset;
-        public uint NumRelocEntries;
-        public uint Flags;
-        public uint Reserved1;
-        public uint Reserved2;
-        public uint Reserved3;
     }
 
     internal class MachOLinkEditDataCommand

Il2CppInspector/FileFormatReaders/MachOReader.cs

@@ -13,20 +13,45 @@ using NoisyCowStudios.Bin2Object;
 
 namespace Il2CppInspector
 {
-    internal class MachOReader : FileFormatReader<MachOReader>
+    internal class MachOReader32 : MachOReader<uint, MachOReader32>
     {
-        private MachOHeader header;
+        public MachOReader32(Stream stream) : base(stream) { }
+
+        public override int Bits => 32;
+
+        protected override bool checkMagicLE(MachO magic) => magic == MachO.MH_MAGIC;
+        protected override bool checkMagicBE(MachO magic) => magic == MachO.MH_CIGAM;
+
+        protected override MachO lc_Segment => MachO.LC_SEGMENT;
+    }
+
+    internal class MachOReader64 : MachOReader<ulong, MachOReader64>
+    {
+        public MachOReader64(Stream stream) : base(stream) { }
+
+        public override int Bits => 64;
+
+        protected override bool checkMagicLE(MachO magic) => magic == MachO.MH_MAGIC_64;
+        protected override bool checkMagicBE(MachO magic) => magic == MachO.MH_CIGAM_64;
+
+        protected override MachO lc_Segment => MachO.LC_SEGMENT_64;
+    }
+
+    // We need this convoluted generic TReader declaration so that "static T FileFormatReader.Load(Stream)"
+    // is inherited to MachOReader32/64 with a correct definition of T
+    internal abstract class MachOReader<TWord, TReader> : FileFormatReader<TReader> where TWord : struct where TReader : FileFormatReader<TReader>
+    {
+        private MachOHeader<TWord> header;
+        private readonly List<MachOSection<TWord>> sections = new List<MachOSection<TWord>>();
         private uint pFuncTable;
         private uint sFuncTable;
-        private bool is64;
-        private List<MachOSection> sections = new List<MachOSection>();
-        private List<MachOSection64> sections64 = new List<MachOSection64>();
 
-        public MachOReader(Stream stream) : base(stream) { }
+        protected MachOReader(Stream stream) : base(stream) { }
 
         public override string Format => "Mach-O";
 
-        public override string Arch => (MachO)header.CPUType switch {
+        public override string Arch => (MachO)header.CPUType switch
+        {
             MachO.CPU_TYPE_ARM => "ARM",
             MachO.CPU_TYPE_ARM64 => "ARM64",
             MachO.CPU_TYPE_X86 => "x86",
@@ -34,59 +59,44 @@ namespace Il2CppInspector
             _ => "Unsupported"
         };
 
-        public override int Bits => is64 ? 64 : 32;
+        protected abstract bool checkMagicLE(MachO magic);
+        protected abstract bool checkMagicBE(MachO magic);
+        protected abstract MachO lc_Segment { get; }
 
         protected override bool Init() {
             // Detect endianness - default is little-endianness
             MachO magic = (MachO)ReadUInt32();
-            if (magic == MachO.MH_CIGAM || magic == MachO.MH_CIGAM_64) {
+
+            if (checkMagicBE(magic))
                 Endianness = Endianness.Big;
-            }
+
-            else if (magic != MachO.MH_MAGIC && magic != MachO.MH_MAGIC_64) {
+            if (!checkMagicBE(magic) && !checkMagicLE(magic))
                 return false;
-            }
 
-            Position -= sizeof(uint);
+            header = ReadObject<MachOHeader<TWord>>(0);
-            header = ReadObject<MachOHeader>();
-
-            // 64-bit files have an extra 4 bytes after the header
-            is64 = false;
-            if (magic == MachO.MH_MAGIC_64) {
-                is64 = true;
-                ReadUInt32();
-            }
 
             // Must be executable file
-            if ((MachO) header.FileType != MachO.MH_EXECUTE)
+            if ((MachO)header.FileType != MachO.MH_EXECUTE)
                 return false;
 
             MachOLinkEditDataCommand functionStarts = null;
 
+            // Process load commands
             for (var c = 0; c < header.NumCommands; c++) {
                 var startPos = Position;
                 var loadCommand = ReadObject<MachOLoadCommand>();
 
-                if ((MachO)loadCommand.Command == MachO.LC_SEGMENT) {
+                if ((MachO)loadCommand.Command == lc_Segment) {
-                    var segment = ReadObject<MachOSegmentCommand>();
+                    var segment = ReadObject<MachOSegmentCommand<TWord>>();
                     if (segment.Name == "__TEXT" || segment.Name == "__DATA") {
                         for (int s = 0; s < segment.NumSections; s++) {
-                            var section = ReadObject<MachOSection>();
+                            var section = ReadObject<MachOSection<TWord>>();
                             sections.Add(section);
-                            if (section.Name == "__text")
+                            if (section.Name == "__text") {
-                                GlobalOffset = section.Address - section.ImageOffset;
+                                GlobalOffset = (ulong)Convert.ChangeType(section.Address, typeof(ulong)) - section.ImageOffset;
                             }
                         }
                     }
-                else if ((MachO)loadCommand.Command == MachO.LC_SEGMENT_64) {
-                    var segment = ReadObject<MachOSegmentCommand64>();
-                    if (segment.Name == "__TEXT" || segment.Name == "__DATA") {
-                        for (int s = 0; s < segment.NumSections; s++) {
-                            var section64 = ReadObject<MachOSection64>();
-                            sections64.Add(section64);
-                            if (section64.Name == "__text")
-                                GlobalOffset = (uint)section64.Address - section64.ImageOffset;
-                        }
-                    }
                 }
 
                 if ((MachO)loadCommand.Command == MachO.LC_FUNCTION_STARTS) {
@@ -133,12 +143,8 @@ namespace Il2CppInspector
         }
 
         public override uint MapVATR(ulong uiAddr) {
-            if (!is64) {
+            var section = sections.First(x => uiAddr >= (uint)(object)x.Address && uiAddr <= (uint)(object)x.Address + (uint)(object)x.Size);
-                var section = sections.First(x => uiAddr >= x.Address && uiAddr <= (x.Address + x.Size));
+            return (uint) (uiAddr - ((ulong) Convert.ChangeType(section.Address, typeof(ulong)) - section.ImageOffset));
-                return (uint) (uiAddr - (section.Address - section.ImageOffset));
-            }
-            var section64 = sections64.First(x => uiAddr >= x.Address && uiAddr <= (x.Address + x.Size));
-            return (uint) (uiAddr - ((uint)section64.Address - section64.ImageOffset));
         }
     }
 }

Il2CppInspector/FileFormatReaders/UBReader.cs

@@ -1,5 +1,5 @@
 /*
-    Copyright 2017 Katy Coe - http://www.hearthcode.org - http://www.djkaty.com
+    Copyright 2017-2019 Katy Coe - http://www.hearthcode.org - http://www.djkaty.com
 
     All rights reserved.
 */
@@ -37,7 +37,8 @@ namespace Il2CppInspector
 
                 Position = arch.Offset;
                 Endianness = Endianness.Little;
-                return MachOReader.Load(new MemoryStream(ReadBytes((int)arch.Size)));
+                var s = new MemoryStream(ReadBytes((int) arch.Size));
+                return (IFileFormatReader) MachOReader32.Load(s) ?? MachOReader64.Load(s);
             }
         }
     }

README.md

@@ -2,6 +2,7 @@
 Extract types, methods, properties and fields from Unity IL2CPP binaries.
 
 * Supports ELF (Android .so), PE (Windows .exe), Mach-O (Apple iOS/Mac) and Universal Binary (Fat Mach-O) file formats
+* 64-bit support for Mach-O files
 * Supports ARMv7, ARMv7 Thumb T1 and x86 architectures regardless of file format
 * Supports metadata versions 21, 22, 23, 24, 24.1 (Unity 2018.3+) and 24.2 (Unity 2019+)
 * No manual reverse-engineering required; all data is calculated automatically