522 lines
27 KiB
C#
522 lines
27 KiB
C#
/*
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Copyright 2017 Perfare - https://github.com/Perfare/Il2CppDumper
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Copyright 2017-2020 Katy Coe - http://www.djkaty.com - https://github.com/djkaty
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All rights reserved.
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*/
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using System;
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using System.Collections.Generic;
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using System.Diagnostics;
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using System.IO;
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using System.Linq;
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using System.Reflection;
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using System.Text;
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namespace Il2CppInspector
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{
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internal class ElfReader32 : ElfReader<uint, elf_32_phdr, elf_32_sym, ElfReader32, Convert32>
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{
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public ElfReader32(Stream stream) : base(stream) {
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ElfReloc.GetRelocType = info => (Elf) (info & 0xff);
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ElfReloc.GetSymbolIndex = info => info >> 8;
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}
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public override int Bits => 32;
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protected override Elf ArchClass => Elf.ELFCLASS32;
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protected override void Write(BinaryWriter writer, uint value) => writer.Write(value);
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}
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internal class ElfReader64 : ElfReader<ulong, elf_64_phdr, elf_64_sym, ElfReader64, Convert64>
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{
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public ElfReader64(Stream stream) : base(stream) {
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ElfReloc.GetRelocType = info => (Elf) (info & 0xffff_ffff);
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ElfReloc.GetSymbolIndex = info => info >> 32;
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}
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public override int Bits => 64;
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protected override Elf ArchClass => Elf.ELFCLASS64;
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protected override void Write(BinaryWriter writer, ulong value) => writer.Write(value);
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}
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interface IElfReader
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{
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uint GetPLTAddress();
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}
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internal abstract class ElfReader<TWord, TPHdr, TSym, TReader, TConvert> : FileFormatReader<TReader>, IElfReader
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where TWord : struct
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where TPHdr : Ielf_phdr<TWord>, new()
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where TSym : Ielf_sym<TWord>, new()
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where TConvert : IWordConverter<TWord>, new()
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where TReader : FileFormatReader<TReader>
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{
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private readonly TConvert conv = new TConvert();
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// Internal relocation entry helper
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protected class ElfReloc
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{
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public Elf Type;
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public TWord Offset;
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public TWord? Addend;
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public TWord SymbolTable;
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public TWord SymbolIndex;
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// Equality based on target address
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public override bool Equals(object obj) => obj is ElfReloc reloc && Equals(reloc);
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public bool Equals(ElfReloc other) {
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return Offset.Equals(other.Offset);
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}
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public override int GetHashCode() => Offset.GetHashCode();
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// Cast operators (makes the below code MUCH easier to read)
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public ElfReloc(elf_rel<TWord> rel, TWord symbolTable) {
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Offset = rel.r_offset;
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Addend = null;
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Type = GetRelocType(rel.r_info);
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SymbolIndex = GetSymbolIndex(rel.r_info);
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SymbolTable = symbolTable;
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}
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public ElfReloc(elf_rela<TWord> rela, TWord symbolTable)
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: this(new elf_rel<TWord> { r_info = rela.r_info, r_offset = rela.r_offset }, symbolTable) =>
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Addend = rela.r_addend;
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public static Func<TWord, Elf> GetRelocType;
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public static Func<TWord, TWord> GetSymbolIndex;
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}
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// See also: https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/operators/sizeof
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private int Sizeof(Type type) {
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int size = 0;
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foreach (var i in type.GetTypeInfo().GetFields()) {
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if (i.FieldType == typeof(byte) || i.FieldType == typeof(sbyte))
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size += sizeof(byte);
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if (i.FieldType == typeof(long) || i.FieldType == typeof(ulong))
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size += sizeof(ulong);
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if (i.FieldType == typeof(int) || i.FieldType == typeof(uint))
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size += sizeof(uint);
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if (i.FieldType == typeof(short) || i.FieldType == typeof(ushort))
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size += sizeof(ushort);
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}
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return size;
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}
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private TPHdr[] program_header_table;
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private elf_shdr<TWord>[] section_header_table;
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private elf_dynamic<TWord>[] dynamic_table;
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private elf_header<TWord> elf_header;
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private Dictionary<string, elf_shdr<TWord>> sectionByName = new Dictionary<string, elf_shdr<TWord>>();
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private List<(uint Start, uint End)> reverseMapExclusions = new List<(uint Start, uint End)>();
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public ElfReader(Stream stream) : base(stream) { }
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public override string Format => Bits == 32 ? "ELF" : "ELF64";
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public override string Arch => (Elf) elf_header.e_machine switch {
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Elf.EM_386 => "x86",
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Elf.EM_ARM => "ARM",
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Elf.EM_X86_64 => "x64",
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Elf.EM_AARCH64 => "ARM64",
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_ => "Unsupported"
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};
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public override int Bits => (elf_header.m_arch == (uint) Elf.ELFCLASS64) ? 64 : 32;
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private elf_shdr<TWord> getSection(Elf sectionIndex) => section_header_table.FirstOrDefault(x => x.sh_type == (uint) sectionIndex);
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private IEnumerable<elf_shdr<TWord>> getSections(Elf sectionIndex) => section_header_table.Where(x => x.sh_type == (uint) sectionIndex);
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private TPHdr getProgramHeader(Elf programIndex) => program_header_table.FirstOrDefault(x => x.p_type == (uint) programIndex);
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private elf_dynamic<TWord> getDynamic(Elf dynamicIndex) => dynamic_table?.FirstOrDefault(x => (Elf) conv.ULong(x.d_tag) == dynamicIndex);
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private Dictionary<string, Symbol> symbolTable = new Dictionary<string, Symbol>();
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private List<Export> exports = new List<Export>();
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protected abstract Elf ArchClass { get; }
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protected abstract void Write(BinaryWriter writer, TWord value);
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protected override bool Init() {
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elf_header = ReadObject<elf_header<TWord>>();
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// Check for magic bytes
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if ((Elf) elf_header.m_dwFormat != Elf.ELFMAG)
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return false;
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// Ensure supported architecture
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if ((Elf) elf_header.m_arch != ArchClass)
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return false;
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// Get PHT and SHT
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program_header_table = ReadArray<TPHdr>(conv.Long(elf_header.e_phoff), elf_header.e_phnum);
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section_header_table = ReadArray<elf_shdr<TWord>>(conv.Long(elf_header.e_shoff), elf_header.e_shnum);
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// Get section name mappings if there are any
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// This is currently only used to defeat the XOR obfuscation handled below
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// Note: There can be more than one section with the same name, or unnamed; we take the first section with a given name
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if (elf_header.e_shtrndx < section_header_table.Length) {
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var pStrtab = section_header_table[elf_header.e_shtrndx].sh_offset;
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foreach (var section in section_header_table) {
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var name = ReadNullTerminatedString(conv.Long(pStrtab) + section.sh_name);
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sectionByName.TryAdd(name, section);
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}
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}
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// Get dynamic table if it exists
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if (getProgramHeader(Elf.PT_DYNAMIC) is TPHdr PT_DYNAMIC)
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dynamic_table = ReadArray<elf_dynamic<TWord>>(conv.Long(PT_DYNAMIC.p_offset), (int) (conv.Long(PT_DYNAMIC.p_filesz) / Sizeof(typeof(elf_dynamic<TWord>))));
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// Get offset of code section
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var codeSegment = program_header_table.First(x => ((Elf) x.p_flags & Elf.PF_X) == Elf.PF_X);
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GlobalOffset = conv.ULong(conv.Sub(codeSegment.p_vaddr, codeSegment.p_offset));
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// Find all relocations; target address => (rela header (rels are converted to rela), symbol table base address, is rela?)
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var rels = new HashSet<ElfReloc>();
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StatusUpdate("Finding relocations");
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// Two types: add value from offset in image, and add value from specified addend
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foreach (var relSection in getSections(Elf.SHT_REL)) {
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reverseMapExclusions.Add(((uint) conv.Int(relSection.sh_offset), (uint) (conv.Int(relSection.sh_offset) + conv.Int(relSection.sh_size) - 1)));
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rels.UnionWith(
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from rel in ReadArray<elf_rel<TWord>>(conv.Long(relSection.sh_offset), conv.Int(conv.Div(relSection.sh_size, relSection.sh_entsize)))
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select new ElfReloc(rel, section_header_table[relSection.sh_link].sh_offset));
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}
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foreach (var relaSection in getSections(Elf.SHT_RELA)) {
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reverseMapExclusions.Add(((uint) conv.Int(relaSection.sh_offset), (uint) (conv.Int(relaSection.sh_offset) + conv.Int(relaSection.sh_size) - 1)));
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rels.UnionWith(
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from rela in ReadArray<elf_rela<TWord>>(conv.Long(relaSection.sh_offset), conv.Int(conv.Div(relaSection.sh_size, relaSection.sh_entsize)))
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select new ElfReloc(rela, section_header_table[relaSection.sh_link].sh_offset));
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}
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// Relocations in dynamic section
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if (getDynamic(Elf.DT_REL) is elf_dynamic<TWord> dt_rel) {
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var dt_rel_count = conv.Int(conv.Div(getDynamic(Elf.DT_RELSZ).d_un, getDynamic(Elf.DT_RELENT).d_un));
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var dt_item_size = Sizeof(typeof(elf_rel<TWord>));
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var dt_start = MapVATR(conv.ULong(dt_rel.d_un));
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var dt_rel_list = ReadArray<elf_rel<TWord>>(dt_start, dt_rel_count);
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var dt_symtab = getDynamic(Elf.DT_SYMTAB).d_un;
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reverseMapExclusions.Add((dt_start, (uint) (dt_start + dt_rel_count * dt_item_size - 1)));
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rels.UnionWith(from rel in dt_rel_list select new ElfReloc(rel, dt_symtab));
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}
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if (getDynamic(Elf.DT_RELA) is elf_dynamic<TWord> dt_rela) {
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var dt_rela_count = conv.Int(conv.Div(getDynamic(Elf.DT_RELASZ).d_un, getDynamic(Elf.DT_RELAENT).d_un));
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var dt_item_size = Sizeof(typeof(elf_rela<TWord>));
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var dt_start = MapVATR(conv.ULong(dt_rela.d_un));
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var dt_rela_list = ReadArray<elf_rela<TWord>>(dt_start, dt_rela_count);
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var dt_symtab = getDynamic(Elf.DT_SYMTAB).d_un;
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reverseMapExclusions.Add((dt_start, (uint) (dt_start + dt_rela_count * dt_item_size - 1)));
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rels.UnionWith(from rela in dt_rela_list select new ElfReloc(rela, dt_symtab));
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}
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// Process relocations
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// WARNING: This modifies the stream passed in the constructor
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if (BaseStream is FileStream)
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throw new InvalidOperationException("Input stream to ElfReader is a file. Please supply a mutable stream source.");
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using var writer = new BinaryWriter(BaseStream, Encoding.Default, true);
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var relsz = Sizeof(typeof(TSym));
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var currentRel = 0;
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var totalRel = rels.Count();
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foreach (var rel in rels) {
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currentRel++;
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if (currentRel % 1000 == 0)
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StatusUpdate($"Processing relocations ({currentRel * 100 / totalRel:F0}%)");
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var symValue = ReadObject<TSym>(conv.Long(rel.SymbolTable) + conv.Long(rel.SymbolIndex) * relsz).st_value; // S
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// Ignore relocations into memory addresses not mapped from the image
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try {
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Position = MapVATR(conv.ULong(rel.Offset));
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}
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catch (InvalidOperationException) {
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continue;
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}
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// The addend is specified in the struct for rela, and comes from the target location for rel
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var addend = rel.Addend ?? ReadObject<TWord>(); // A
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// Only handle relocation types we understand, skip the rest
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// Relocation types from https://docs.oracle.com/cd/E23824_01/html/819-0690/chapter6-54839.html#scrolltoc
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// and https://studfiles.net/preview/429210/page:18/
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// and http://infocenter.arm.com/help/topic/com.arm.doc.ihi0056b/IHI0056B_aaelf64.pdf (AArch64)
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(TWord newValue, bool recognized) result = (rel.Type, (Elf) elf_header.e_machine) switch {
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(Elf.R_ARM_ABS32, Elf.EM_ARM) => (conv.Add(symValue, addend), true), // S + A
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(Elf.R_ARM_REL32, Elf.EM_ARM) => (conv.Add(conv.Sub(symValue, rel.Offset), addend), true), // S - P + A
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(Elf.R_ARM_COPY, Elf.EM_ARM) => (symValue, true), // S
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(Elf.R_AARCH64_ABS64, Elf.EM_AARCH64) => (conv.Add(symValue, addend), true), // S + A
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(Elf.R_AARCH64_PREL64, Elf.EM_AARCH64) => (conv.Sub(conv.Add(symValue, addend), rel.Offset), true), // S + A - P
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(Elf.R_AARCH64_GLOB_DAT, Elf.EM_AARCH64) => (conv.Add(symValue, addend), true), // S + A
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(Elf.R_AARCH64_JUMP_SLOT, Elf.EM_AARCH64) => (conv.Add(symValue, addend), true), // S + A
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(Elf.R_AARCH64_RELATIVE, Elf.EM_AARCH64) => (conv.Add(symValue, addend), true), // Delta(S) + A
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(Elf.R_386_32, Elf.EM_386) => (conv.Add(symValue, addend), true), // S + A
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(Elf.R_386_PC32, Elf.EM_386) => (conv.Sub(conv.Add(symValue, addend), rel.Offset), true), // S + A - P
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(Elf.R_386_GLOB_DAT, Elf.EM_386) => (symValue, true), // S
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(Elf.R_386_JMP_SLOT, Elf.EM_386) => (symValue, true), // S
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(Elf.R_AMD64_64, Elf.EM_AARCH64) => (conv.Add(symValue, addend), true), // S + A
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_ => (default(TWord), false)
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};
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if (result.recognized) {
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Position = MapVATR(conv.ULong(rel.Offset));
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Write(writer, result.newValue);
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}
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}
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Console.WriteLine($"Processed {rels.Count} relocations");
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// Detect and defeat XOR encryption
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StatusUpdate("Detecting encryption");
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if (getDynamic(Elf.DT_INIT) != null && sectionByName.ContainsKey(".rodata")) {
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// Use the data section to determine IF the file is obfuscated
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var rodataFirstBytes = ReadBytes(conv.Long(sectionByName[".rodata"].sh_offset), 256);
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var xorKeyCandidate = rodataFirstBytes.GroupBy(b => b).OrderByDescending(f => f.Count()).First().Key;
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// We examine the bottom nibble of the 2nd byte and top nibble of 4th byte
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// of the first 64 words (256 bytes) of .text. These values are expected to be primarily 0x0 and 0xE (ARM only)
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var textFirstDWords = ReadArray<uint>(conv.Long(sectionByName[".text"].sh_offset), 64);
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var bottom = textFirstDWords.Select(w => (w >> 8) & 0xF).GroupBy(n => n).OrderByDescending(f => f.Count()).First().Key;
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var top = textFirstDWords.Select(w => w >> 28).GroupBy(n => n).OrderByDescending(f => f.Count()).First().Key;
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var xorKey = (byte) (((top << 4) ^ 0xE0) | bottom);
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if (xorKeyCandidate != 0x00) {
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// Some files may use a striped encryption whereby alternate blocks are encrypted and un-encrypted
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// The first part of each section is always encrypted. Scan for the first unencrypted block and find its size
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// Limit ourselves to 128KB. If no stripe has been found by then, the whole section is probably encrypted
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// We refer to issue #96 where the code uses striped encryption in 4KB blocks
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// We perform heuristics for 128-byte blocks below
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var start = conv.Int(sectionByName[".text"].sh_offset);
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var length = conv.Int(sectionByName[".text"].sh_size);
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var blockSize = 0x80;
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var maxSearchLength = 128 * 1024;
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var firstUnencrypted = 0xffffffff;
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var stripeSize = 0xffffffff;
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var threshold = (blockSize / 4) / 2;
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for (var pos = start; pos < start + maxSearchLength && stripeSize == 0xffffffff; pos += blockSize) {
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var size = Math.Min(blockSize, start + length - pos);
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var dwords = ReadArray<uint>(pos, size / 4);
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var count0 = dwords.Count(w => ((w >> 8) & 0xF) == 0x0);
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var countE = dwords.Count(w => (w >> 28) == 0xE);
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var encrypted = countE < threshold && count0 < threshold;
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if (!encrypted && firstUnencrypted == 0xffffffff)
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firstUnencrypted = (uint) pos;
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if (encrypted && firstUnencrypted != 0xffffffff)
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stripeSize = (uint) pos - firstUnencrypted;
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}
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StatusUpdate("Decrypting");
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Console.WriteLine($"Performing XOR decryption (key: 0x{xorKey:X2}, stripe size: 0x{stripeSize:X4})");
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xorSection(".text", xorKey, stripeSize);
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xorSection(".rodata", xorKey, stripeSize);
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}
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}
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// Detect more sophisticated packing
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// We have seen several examples (eg. #14 and #26) where most of the file is zeroed
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// and packed data is found in the latter third. So far these files always have zeroed .rodata sections
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if (sectionByName.ContainsKey(".rodata")) {
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var rodataBytes = ReadBytes(conv.Long(sectionByName[".rodata"].sh_offset), conv.Int(sectionByName[".rodata"].sh_size));
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if (rodataBytes.All(b => b == 0x00))
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throw new InvalidOperationException("This IL2CPP binary is packed in a way not currently supported by Il2CppInspector and cannot be loaded.");
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}
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// Build symbol and export tables
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processSymbols();
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return true;
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}
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private void xorRange(int offset, int length, byte xorValue) {
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using var writer = new BinaryWriter(BaseStream, Encoding.Default, true);
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var bytes = ReadBytes(offset, length);
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bytes = bytes.Select(b => (byte) (b ^ xorValue)).ToArray();
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writer.Seek(offset, SeekOrigin.Begin);
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writer.Write(bytes);
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}
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private void xorSection(string sectionName, byte xorValue, uint stripeSize) {
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var section = sectionByName[sectionName];
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// First part up to stripe size boundary is always encrypted, first full block is always encrypted
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var start = conv.Int(section.sh_offset);
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var length = conv.Int(section.sh_size);
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// Non-striped
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if (stripeSize == 0xffffffff) {
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xorRange(start, length, xorValue);
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return;
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}
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// Striped
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// The first block's length is the distance to the boundary to the first stripe size + one stripe
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var firstBlockLength = stripeSize;
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if (start % stripeSize != 0)
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firstBlockLength += stripeSize - (uint) (start % stripeSize);
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xorRange(start, (int) firstBlockLength, xorValue);
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// Step forward two stripe sizes at a time, decrypting the first and ignoring the second
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for (var pos = start + firstBlockLength + stripeSize; pos < start + length; pos += stripeSize * 2) {
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var size = Math.Min(stripeSize, start + length - pos);
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xorRange((int) pos, (int) size, xorValue);
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}
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}
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public override Dictionary<string, Symbol> GetSymbolTable() => symbolTable;
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public override IEnumerable<Export> GetExports() => exports;
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private void processSymbols() {
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StatusUpdate("Processing symbols");
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// Three possible symbol tables in ELF files
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var pTables = new List<(TWord offset, TWord count, TWord strings)>();
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// String table (a sequence of null-terminated strings, total length in sh_size
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var SHT_STRTAB = getSection(Elf.SHT_STRTAB);
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if (SHT_STRTAB != null) {
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// Section header shared object symbol table (.symtab)
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if (getSection(Elf.SHT_SYMTAB) is elf_shdr<TWord> SHT_SYMTAB)
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pTables.Add((SHT_SYMTAB.sh_offset, conv.Div(SHT_SYMTAB.sh_size, SHT_SYMTAB.sh_entsize), SHT_STRTAB.sh_offset));
|
|
|
|
// Section header executable symbol table (.dynsym)
|
|
if (getSection(Elf.SHT_DYNSYM) is elf_shdr<TWord> SHT_DYNSYM)
|
|
pTables.Add((SHT_DYNSYM.sh_offset, conv.Div(SHT_DYNSYM.sh_size, SHT_DYNSYM.sh_entsize), SHT_STRTAB.sh_offset));
|
|
}
|
|
|
|
// Symbol table in dynamic section (DT_SYMTAB)
|
|
// Normally the same as .dynsym except that .dynsym may be removed in stripped binaries
|
|
|
|
// Dynamic string table
|
|
if (getDynamic(Elf.DT_STRTAB) is elf_dynamic<TWord> DT_STRTAB) {
|
|
if (getDynamic(Elf.DT_SYMTAB) is elf_dynamic<TWord> DT_SYMTAB) {
|
|
// Find the next pointer in the dynamic table to calculate the length of the symbol table
|
|
var end = (from x in dynamic_table where conv.Gt(x.d_un, DT_SYMTAB.d_un) orderby x.d_un select x).First().d_un;
|
|
|
|
// Dynamic symbol table
|
|
pTables.Add((
|
|
conv.FromUInt(MapVATR(conv.ULong(DT_SYMTAB.d_un))),
|
|
conv.Div(conv.Sub(end, DT_SYMTAB.d_un), Sizeof(typeof(TSym))),
|
|
DT_STRTAB.d_un
|
|
));
|
|
}
|
|
}
|
|
|
|
// Now iterate through all of the symbol and string tables we found to build a full list
|
|
symbolTable.Clear();
|
|
var exportTable = new Dictionary<string, Export>();
|
|
|
|
foreach (var pTab in pTables) {
|
|
var symbol_table = ReadArray<TSym>(conv.Long(pTab.offset), conv.Int(pTab.count));
|
|
|
|
foreach (var symbol in symbol_table) {
|
|
var name = ReadNullTerminatedString(conv.Long(pTab.strings) + symbol.st_name);
|
|
|
|
var type = symbol.type == Elf.STT_FUNC? SymbolType.Function
|
|
: symbol.type == Elf.STT_OBJECT || symbol.type == Elf.STT_COMMON? SymbolType.Name
|
|
: SymbolType.Unknown;
|
|
|
|
if (symbol.st_shndx == (ushort) Elf.SHN_UNDEF)
|
|
type = SymbolType.Import;
|
|
|
|
// Avoid duplicates
|
|
var symbolItem = new Symbol {Name = name, Type = type, VirtualAddress = conv.ULong(symbol.st_value) };
|
|
symbolTable.TryAdd(name, symbolItem);
|
|
if (symbol.st_shndx != (ushort) Elf.SHN_UNDEF)
|
|
exportTable.TryAdd(name, new Export {Name = symbolItem.DemangledName, VirtualAddress = conv.ULong(symbol.st_value)});
|
|
}
|
|
}
|
|
|
|
exports = exportTable.Values.ToList();
|
|
}
|
|
|
|
public override uint[] GetFunctionTable() {
|
|
// INIT_ARRAY contains a list of pointers to initialization functions (not all functions in the binary)
|
|
// INIT_ARRAYSZ contains the size of INIT_ARRAY
|
|
|
|
var init = MapVATR(conv.ULong(getDynamic(Elf.DT_INIT_ARRAY).d_un));
|
|
var size = getDynamic(Elf.DT_INIT_ARRAYSZ).d_un;
|
|
|
|
var init_array = conv.UIntArray(ReadArray<TWord>(init, conv.Int(size) / (Bits / 8)));
|
|
|
|
// Additionally, check if there is an old-style DT_INIT function and include it in the list if so
|
|
if (getDynamic(Elf.DT_INIT) != null)
|
|
init_array = init_array.Concat(conv.UIntArray(new[] { getDynamic(Elf.DT_INIT).d_un })).ToArray();
|
|
|
|
return init_array.Select(x => MapVATR(x)).ToArray();
|
|
}
|
|
|
|
public override IEnumerable<Section> GetSections() {
|
|
// If the sections have been stripped, use the segment list from the PHT instead
|
|
if (section_header_table.All(s => conv.Int(s.sh_offset) == 0)) {
|
|
return program_header_table.Select(p => new Section {
|
|
VirtualStart = conv.ULong(p.p_vaddr),
|
|
VirtualEnd = conv.ULong(p.p_vaddr) + conv.ULong(p.p_memsz) - 1,
|
|
ImageStart = (uint) conv.Int(p.p_offset),
|
|
ImageEnd = (uint) conv.Int(p.p_offset) + (uint) conv.Int(p.p_filesz) - 1,
|
|
|
|
// Not correct but probably the best we can do
|
|
IsData = ((Elf) p.p_flags & Elf.PF_R) != 0,
|
|
IsExec = ((Elf) p.p_flags & Elf.PF_X) != 0,
|
|
IsBSS = conv.Int(p.p_filesz) == 0,
|
|
|
|
Name = string.Empty
|
|
});
|
|
}
|
|
|
|
// Return sections list
|
|
return section_header_table.Select(s => new Section {
|
|
VirtualStart = conv.ULong(s.sh_addr),
|
|
VirtualEnd = conv.ULong(s.sh_addr) + conv.ULong(s.sh_size) - 1,
|
|
ImageStart = (uint) conv.Int(s.sh_offset),
|
|
ImageEnd = (uint) conv.Int(s.sh_offset) + (uint) conv.Int(s.sh_size) - 1,
|
|
|
|
IsData = ((Elf) conv.Int(s.sh_flags) & Elf.SHF_ALLOC) == Elf.SHF_ALLOC && ((Elf) conv.Int(s.sh_flags) & Elf.SHF_EXECINSTR) == 0 && (Elf) s.sh_type == Elf.SHT_PROGBITS,
|
|
IsExec = ((Elf) conv.Int(s.sh_flags) & Elf.SHF_EXECINSTR) == Elf.SHF_EXECINSTR && (Elf) s.sh_type == Elf.SHT_PROGBITS,
|
|
IsBSS = (Elf) s.sh_type == Elf.SHT_NOBITS,
|
|
|
|
Name = sectionByName.First(sbn => conv.Int(sbn.Value.sh_offset) == conv.Int(s.sh_offset)).Key
|
|
});
|
|
}
|
|
|
|
// Map a virtual address to an offset into the image file. Throws an exception if the virtual address is not mapped into the file.
|
|
// Note if uiAddr is a valid segment but filesz < memsz and the adjusted uiAddr falls between the range of filesz and memsz,
|
|
// an exception will be thrown. This area of memory is assumed to contain all zeroes.
|
|
public override uint MapVATR(ulong uiAddr) {
|
|
// Additions in the argument to MapVATR may cause an overflow which should be discarded for 32-bit files
|
|
if (Bits == 32)
|
|
uiAddr &= 0xffff_ffff;
|
|
var program_header_table = this.program_header_table.First(x => uiAddr >= conv.ULong(x.p_vaddr) && uiAddr <= conv.ULong(conv.Add(x.p_vaddr, x.p_filesz)));
|
|
return (uint) (uiAddr - conv.ULong(conv.Sub(program_header_table.p_vaddr, program_header_table.p_offset)));
|
|
}
|
|
|
|
public override ulong MapFileOffsetToVA(uint offset) {
|
|
// Exclude relocation areas
|
|
if (reverseMapExclusions.Any(r => offset >= r.Start && offset <= r.End))
|
|
throw new InvalidOperationException("Attempt to map to a relocation address");
|
|
|
|
var section = program_header_table.First(x => offset >= conv.Int(x.p_offset) && offset < conv.Int(x.p_offset) + conv.Int(x.p_filesz));
|
|
return conv.ULong(section.p_vaddr) + offset - conv.ULong(section.p_offset);
|
|
}
|
|
|
|
// Get the address of the procedure linkage table (.got.plt) which is needed for some disassemblies
|
|
public uint GetPLTAddress() => (uint) conv.ULong(getDynamic(Elf.DT_PLTGOT).d_un);
|
|
}
|
|
} |