使用正确的方式获取符号数量

Author: Perfare

Il2CppDumper/ExecutableFormats/Elf.cs

@@ -190,10 +190,48 @@ private void ReadSymbol()
         {
             try
             {
+                var symbolCount = 0u;
+                var hash = dynamicSection.FirstOrDefault(x => x.d_tag == DT_HASH);
+                if (hash != null)
+                {
+                    var addr = MapVATR(hash.d_un);
+                    Position = addr;
+                    var nbucket = ReadUInt32();
+                    var nchain = ReadUInt32();
+                    symbolCount = nchain;
+                }
+                else
+                {
+                    hash = dynamicSection.First(x => x.d_tag == DT_GNU_HASH);
+                    var addr = MapVATR(hash.d_un);
+                    Position = addr;
+                    var nbuckets = ReadUInt32();
+                    var symoffset = ReadUInt32();
+                    var bloom_size = ReadUInt32();
+                    var bloom_shift = ReadUInt32();
+                    var buckets_address = addr + 16 + (4 * bloom_size);
+                    var buckets = ReadClassArray<uint>(buckets_address, nbuckets);
+                    var last_symbol = buckets.Max();
+                    if (last_symbol < symoffset)
+                    {
+                        symbolCount = symoffset;
+                    }
+                    else
+                    {
+                        var chains_base_address = buckets_address + 4 * nbuckets;
+                        Position = chains_base_address + (last_symbol - symoffset) * 4;
+                        while (true)
+                        {
+                            var chain_entry = ReadUInt32();
+                            ++last_symbol;
+                            if ((chain_entry & 1) != 0)
+                                break;
+                        }
+                        symbolCount = last_symbol;
+                    }
+                }
                 var dynsymOffset = MapVATR(dynamicSection.First(x => x.d_tag == DT_SYMTAB).d_un);
-                var dynstrOffset = MapVATR(dynamicSection.First(x => x.d_tag == DT_STRTAB).d_un);
-                var dynsymSize = dynstrOffset - dynsymOffset;
-                symbolTable = ReadClassArray<Elf32_Sym>(dynsymOffset, (long)dynsymSize / 16);
+                symbolTable = ReadClassArray<Elf32_Sym>(dynsymOffset, symbolCount);
             }
             catch
             {

Il2CppDumper/ExecutableFormats/Elf64.cs

@@ -130,10 +130,48 @@ private void ReadSymbol()
         {
             try
             {
+                var symbolCount = 0u;
+                var hash = dynamicSection.FirstOrDefault(x => x.d_tag == DT_HASH);
+                if (hash != null)
+                {
+                    var addr = MapVATR(hash.d_un);
+                    Position = addr;
+                    var nbucket = ReadUInt32();
+                    var nchain = ReadUInt32();
+                    symbolCount = nchain;
+                }
+                else
+                {
+                    hash = dynamicSection.First(x => x.d_tag == DT_GNU_HASH);
+                    var addr = MapVATR(hash.d_un);
+                    Position = addr;
+                    var nbuckets = ReadUInt32();
+                    var symoffset = ReadUInt32();
+                    var bloom_size = ReadUInt32();
+                    var bloom_shift = ReadUInt32();
+                    var buckets_address = addr + 16 + (8 * bloom_size);
+                    var buckets = ReadClassArray<uint>(buckets_address, nbuckets);
+                    var last_symbol = buckets.Max();
+                    if (last_symbol < symoffset)
+                    {
+                        symbolCount = symoffset;
+                    }
+                    else
+                    {
+                        var chains_base_address = buckets_address + 4 * nbuckets;
+                        Position = chains_base_address + (last_symbol - symoffset) * 4;
+                        while (true)
+                        {
+                            var chain_entry = ReadUInt32();
+                            ++last_symbol;
+                            if ((chain_entry & 1) != 0)
+                                break;
+                        }
+                        symbolCount = last_symbol;
+                    }
+                }
                 var dynsymOffset = MapVATR(dynamicSection.First(x => x.d_tag == DT_SYMTAB).d_un);
-                var dynstrOffset = MapVATR(dynamicSection.First(x => x.d_tag == DT_STRTAB).d_un);
-                var dynsymSize = dynstrOffset - dynsymOffset;
-                symbolTable = ReadClassArray<Elf64_Sym>(dynsymOffset, (long)dynsymSize / 24L);
+                symbolTable = ReadClassArray<Elf64_Sym>(dynsymOffset, symbolCount);
             }
             catch
             {

Il2CppDumper/ExecutableFormats/ElfClass.cs

@@ -172,6 +172,7 @@ public static class ElfConstants
         public const int DT_JMPREL = 23;
         public const int DT_INIT_ARRAY = 25;
         public const int DT_FINI_ARRAY = 26;
+        public const int DT_GNU_HASH = 0x6ffffef5;
 
         public const uint SHT_LOUSER = 0x80000000;