Esempio n. 1
0
        /// <summary>
        /// Relocates a module in memory.
        /// </summary>
        /// <author>Ruben Boonen (@FuzzySec)</author>
        /// <param name="PEINFO">Module meta data struct (PE.PE_META_DATA).</param>
        /// <param name="ModuleMemoryBase">Base address of the module in memory.</param>
        /// <returns>void</returns>
        public static void RelocateModule(PE.PE_META_DATA PEINFO, IntPtr ModuleMemoryBase)
        {
            PE.IMAGE_DATA_DIRECTORY idd = PEINFO.Is32Bit ? PEINFO.OptHeader32.BaseRelocationTable : PEINFO.OptHeader64.BaseRelocationTable;
            Int64 ImageDelta            = PEINFO.Is32Bit ? (Int64)((UInt64)ModuleMemoryBase - PEINFO.OptHeader32.ImageBase) :
                                          (Int64)((UInt64)ModuleMemoryBase - PEINFO.OptHeader64.ImageBase);

            // Ptr for the base reloc table
            IntPtr pRelocTable         = (IntPtr)((UInt64)ModuleMemoryBase + idd.VirtualAddress);
            Int32  nextRelocTableBlock = -1;

            // Loop reloc blocks
            while (nextRelocTableBlock != 0)
            {
                PE.IMAGE_BASE_RELOCATION ibr = new PE.IMAGE_BASE_RELOCATION();
                ibr = (PE.IMAGE_BASE_RELOCATION)Marshal.PtrToStructure(pRelocTable, typeof(PE.IMAGE_BASE_RELOCATION));

                Int64 RelocCount = ((ibr.SizeOfBlock - Marshal.SizeOf(ibr)) / 2);
                for (int i = 0; i < RelocCount; i++)
                {
                    // Calculate reloc entry ptr
                    IntPtr pRelocEntry = (IntPtr)((UInt64)pRelocTable + (UInt64)Marshal.SizeOf(ibr) + (UInt64)(i * 2));
                    UInt16 RelocValue  = (UInt16)Marshal.ReadInt16(pRelocEntry);

                    // Parse reloc value
                    // The type should only ever be 0x0, 0x3, 0xA
                    // https://docs.microsoft.com/en-us/windows/win32/debug/pe-format#base-relocation-types
                    UInt16 RelocType  = (UInt16)(RelocValue >> 12);
                    UInt16 RelocPatch = (UInt16)(RelocValue & 0xfff);

                    // Perform relocation
                    if (RelocType != 0) // IMAGE_REL_BASED_ABSOLUTE (0 -> skip reloc)
                    {
                        try
                        {
                            IntPtr pPatch = (IntPtr)((UInt64)ModuleMemoryBase + ibr.VirtualAdress + RelocPatch);
                            if (RelocType == 0x3) // IMAGE_REL_BASED_HIGHLOW (x86)
                            {
                                Int32 OriginalPtr = Marshal.ReadInt32(pPatch);
                                Marshal.WriteInt32(pPatch, (OriginalPtr + (Int32)ImageDelta));
                            }
                            else // IMAGE_REL_BASED_DIR64 (x64)
                            {
                                Int64 OriginalPtr = Marshal.ReadInt64(pPatch);
                                Marshal.WriteInt64(pPatch, (OriginalPtr + ImageDelta));
                            }
                        }
                        catch
                        {
                            throw new InvalidOperationException("Memory access violation.");
                        }
                    }
                }

                // Check for next block
                pRelocTable         = (IntPtr)((UInt64)pRelocTable + ibr.SizeOfBlock);
                nextRelocTableBlock = Marshal.ReadInt32(pRelocTable);
            }
        }
Esempio n. 2
0
        /// <summary>
        /// Rewrite IAT for manually mapped module.
        /// </summary>
        /// <author>Ruben Boonen (@FuzzySec)</author>
        /// <param name="PEINFO">Module meta data struct (PE.PE_META_DATA).</param>
        /// <param name="ModuleMemoryBase">Base address of the module in memory.</param>
        /// <returns>void</returns>
        public static void RewriteModuleIAT(PE.PE_META_DATA PEINFO, IntPtr ModuleMemoryBase)
        {
            PE.IMAGE_DATA_DIRECTORY idd = PEINFO.Is32Bit ? PEINFO.OptHeader32.ImportTable : PEINFO.OptHeader64.ImportTable;

            // Ptr for the base import directory
            IntPtr pImportTable = (IntPtr)((UInt64)ModuleMemoryBase + idd.VirtualAddress);

            // Get API Set mapping dictionary if on Win10+
            Execute.Native.OSVERSIONINFOEX OSVersion = new Execution.Native.OSVERSIONINFOEX();
            DynamicInvoke.Native.RtlGetVersion(ref OSVersion);
            Dictionary <string, string> ApiSetDict = new Dictionary <string, string>();

            if (OSVersion.MajorVersion >= 10)
            {
                ApiSetDict = DynamicInvoke.Generic.GetApiSetMapping();
            }

            // Loop IID's
            int counter = 0;

            Execute.Win32.Kernel32.IMAGE_IMPORT_DESCRIPTOR iid = new Execute.Win32.Kernel32.IMAGE_IMPORT_DESCRIPTOR();
            iid = (Execute.Win32.Kernel32.IMAGE_IMPORT_DESCRIPTOR)Marshal.PtrToStructure(
                (IntPtr)((UInt64)pImportTable + (uint)(Marshal.SizeOf(iid) * counter)),
                typeof(Execute.Win32.Kernel32.IMAGE_IMPORT_DESCRIPTOR)
                );
            while (iid.Name != 0)
            {
                // Get DLL
                string DllName = string.Empty;
                try
                {
                    DllName = Marshal.PtrToStringAnsi((IntPtr)((UInt64)ModuleMemoryBase + iid.Name));
                }
                catch { }

                // Loop imports
                if (DllName == string.Empty)
                {
                    throw new InvalidOperationException("Failed to read DLL name.");
                }
                else
                {
                    // API Set DLL?
                    if (OSVersion.MajorVersion >= 10 && (DllName.StartsWith("api-") || DllName.StartsWith("ext-")) &&
                        ApiSetDict.ContainsKey(DllName) && ApiSetDict[DllName].Length > 0)
                    {
                        // Not all API set DLL's have a registered host mapping
                        DllName = ApiSetDict[DllName];
                    }

                    // Check and / or load DLL
                    IntPtr hModule = DynamicInvoke.Generic.GetLoadedModuleAddress(DllName);
                    if (hModule == IntPtr.Zero)
                    {
                        hModule = DynamicInvoke.Generic.LoadModuleFromDisk(DllName);
                        if (hModule == IntPtr.Zero)
                        {
                            throw new FileNotFoundException(DllName + ", unable to find the specified file.");
                        }
                    }

                    // Loop thunks
                    if (PEINFO.Is32Bit)
                    {
                        PE.IMAGE_THUNK_DATA32 oft_itd = new PE.IMAGE_THUNK_DATA32();
                        for (int i = 0; true; i++)
                        {
                            oft_itd = (PE.IMAGE_THUNK_DATA32)Marshal.PtrToStructure((IntPtr)((UInt64)ModuleMemoryBase + iid.OriginalFirstThunk + (UInt32)(i * (sizeof(UInt32)))), typeof(PE.IMAGE_THUNK_DATA32));
                            IntPtr ft_itd = (IntPtr)((UInt64)ModuleMemoryBase + iid.FirstThunk + (UInt64)(i * (sizeof(UInt32))));
                            if (oft_itd.AddressOfData == 0)
                            {
                                break;
                            }

                            if (oft_itd.AddressOfData < 0x80000000) // !IMAGE_ORDINAL_FLAG32
                            {
                                IntPtr pImpByName = (IntPtr)((UInt64)ModuleMemoryBase + oft_itd.AddressOfData + sizeof(UInt16));
                                IntPtr pFunc      = IntPtr.Zero;
                                pFunc = DynamicInvoke.Generic.GetNativeExportAddress(hModule, Marshal.PtrToStringAnsi(pImpByName));

                                // Write ProcAddress
                                Marshal.WriteInt32(ft_itd, pFunc.ToInt32());
                            }
                            else
                            {
                                ulong  fOrdinal = oft_itd.AddressOfData & 0xFFFF;
                                IntPtr pFunc    = IntPtr.Zero;
                                pFunc = DynamicInvoke.Generic.GetNativeExportAddress(hModule, (short)fOrdinal);

                                // Write ProcAddress
                                Marshal.WriteInt32(ft_itd, pFunc.ToInt32());
                            }
                        }
                    }
                    else
                    {
                        PE.IMAGE_THUNK_DATA64 oft_itd = new PE.IMAGE_THUNK_DATA64();
                        for (int i = 0; true; i++)
                        {
                            oft_itd = (PE.IMAGE_THUNK_DATA64)Marshal.PtrToStructure((IntPtr)((UInt64)ModuleMemoryBase + iid.OriginalFirstThunk + (UInt64)(i * (sizeof(UInt64)))), typeof(PE.IMAGE_THUNK_DATA64));
                            IntPtr ft_itd = (IntPtr)((UInt64)ModuleMemoryBase + iid.FirstThunk + (UInt64)(i * (sizeof(UInt64))));
                            if (oft_itd.AddressOfData == 0)
                            {
                                break;
                            }

                            if (oft_itd.AddressOfData < 0x8000000000000000) // !IMAGE_ORDINAL_FLAG64
                            {
                                IntPtr pImpByName = (IntPtr)((UInt64)ModuleMemoryBase + oft_itd.AddressOfData + sizeof(UInt16));
                                IntPtr pFunc      = IntPtr.Zero;
                                pFunc = DynamicInvoke.Generic.GetNativeExportAddress(hModule, Marshal.PtrToStringAnsi(pImpByName));

                                // Write pointer
                                Marshal.WriteInt64(ft_itd, pFunc.ToInt64());
                            }
                            else
                            {
                                ulong  fOrdinal = oft_itd.AddressOfData & 0xFFFF;
                                IntPtr pFunc    = IntPtr.Zero;
                                pFunc = DynamicInvoke.Generic.GetNativeExportAddress(hModule, (short)fOrdinal);

                                // Write pointer
                                Marshal.WriteInt64(ft_itd, pFunc.ToInt64());
                            }
                        }
                    }
                    counter++;
                    iid = (Execute.Win32.Kernel32.IMAGE_IMPORT_DESCRIPTOR)Marshal.PtrToStructure(
                        (IntPtr)((UInt64)pImportTable + (uint)(Marshal.SizeOf(iid) * counter)),
                        typeof(Execute.Win32.Kernel32.IMAGE_IMPORT_DESCRIPTOR)
                        );
                }
            }
        }