Re-factor Metadata and file format code

2017-10-23 14:03:41 +02:00
parent 6e6e7d86e0
commit 474faa009c
12 changed files with 91 additions and 99 deletions
--- a/Il2CppInspector/FileFormatReaders/ElfReader.cs
+++ b/Il2CppInspector/FileFormatReaders/ElfReader.cs
@@ -0,0 +1,93 @@
+/*
+    Copyright 2017 Perfare - https://github.com/Perfare/Il2CppDumper
+    Copyright 2017 Katy Coe - http://www.hearthcode.org - http://www.djkaty.com
+
+    All rights reserved.
+*/
+
+using System;
+using System.IO;
+using System.Linq;
+
+namespace Il2CppInspector
+{
+    internal class ElfReader : FileFormatReader<ElfReader>
+    {
+        private program_header_table[] program_table_element;
+        private elf_header elf_header;
+
+        public ElfReader(Stream stream) : base(stream) { }
+
+        public override string Arch {
+            get {
+                switch (elf_header.e_machine) {
+                    case 0x03:
+                        return "x86";
+                    case 0x28:
+                        return "ARM";
+                    default:
+                        return "Unsupported";
+                }
+            }
+        }
+
+        protected override bool Init() {
+            elf_header = ReadObject<elf_header>();
+
+            if (elf_header.m_dwFormat != 0x464c457f) {
+                // Not an ELF file
+                return false;
+            }
+            if (elf_header.m_arch == 2)//64
+            {
+                // 64-bit not supported
+                return false;
+            }
+            program_table_element = ReadArray<program_header_table>(elf_header.e_phoff, elf_header.e_phnum);
+            return true;
+        }
+
+        public override uint[] GetSearchLocations() {
+            // Find dynamic section
+            var dynamic = new elf_32_shdr();
+            var PT_DYNAMIC = program_table_element.First(x => x.p_type == 2u);
+            dynamic.sh_offset = PT_DYNAMIC.p_offset;
+            dynamic.sh_size = PT_DYNAMIC.p_filesz;
+
+            // We need GOT, INIT_ARRAY and INIT_ARRAYSZ
+            uint _GLOBAL_OFFSET_TABLE_ = 0;
+            var init_array = new elf_32_shdr();
+            Position = dynamic.sh_offset;
+            var dynamicend = dynamic.sh_offset + dynamic.sh_size;
+            while (Position < dynamicend) {
+                var tag = ReadInt32();
+                if (tag == 3) //DT_PLTGOT
+                {
+                    _GLOBAL_OFFSET_TABLE_ = ReadUInt32();
+                    continue;
+                }
+                else if (tag == 25) //DT_INIT_ARRAY
+                {
+                    init_array.sh_offset = MapVATR(ReadUInt32());
+                    continue;
+                }
+                else if (tag == 27) //DT_INIT_ARRAYSZ
+                {
+                    init_array.sh_size = ReadUInt32();
+                    continue;
+                }
+                Position += 4;
+            }
+            if (_GLOBAL_OFFSET_TABLE_ == 0)
+                throw new InvalidOperationException("Unable to get GLOBAL_OFFSET_TABLE from PT_DYNAMIC");
+            GlobalOffset = _GLOBAL_OFFSET_TABLE_;
+            return ReadArray<uint>(init_array.sh_offset, (int) init_array.sh_size / 4);
+        }
+
+        public override uint MapVATR(uint uiAddr)
+        {
+            var program_header_table = program_table_element.First(x => uiAddr >= x.p_vaddr && uiAddr <= (x.p_vaddr + x.p_memsz));
+            return uiAddr - (program_header_table.p_vaddr - program_header_table.p_offset);
+        }
+    }
+}