#include <windows.h>

#include <winnt.h>

#include <stddef.h>

#include <tchar.h>

#ifdef DEBUG_OUTPUT

#include <stdio.h>

#if _MSC_VER

// Disable warning about data -> function pointer conversion

#pragma warning(disable:4055)

// C4244: conversion from 'uintptr_t' to 'DWORD', possible loss of data.

#pragma warning(error: 4244)

#pragma warning(error: 4267)

#define inline __inline

#ifndef IMAGE_SIZEOF_BASE_RELOCATION

#define IMAGE_SIZEOF_BASE_RELOCATION (sizeof(IMAGE_BASE_RELOCATION))

#ifdef _WIN64

#define HOST_MACHINE IMAGE_FILE_MACHINE_AMD64

#define HOST_MACHINE IMAGE_FILE_MACHINE_I386

#include "MemoryModule.h"

struct ExportNameEntry {

LPCSTR name;

WORD idx;

};

typedef BOOL(WINAPI* DllEntryProc)(HINSTANCE hinstDLL, DWORD fdwReason, LPVOID lpReserved);

typedef int (WINAPI* ExeEntryProc)(void);

#ifdef _WIN64

typedef struct POINTER_LIST {

struct POINTER_LIST* next;

void* address;

} POINTER_LIST;

typedef struct {

PIMAGE_NT_HEADERS headers;

unsigned char* codeBase;

HCUSTOMMODULE* modules;

int numModules;

BOOL initialized;

BOOL isDLL;

BOOL isRelocated;

CustomAllocFunc alloc;

CustomFreeFunc free;

CustomLoadLibraryFunc loadLibrary;

CustomGetProcAddressFunc getProcAddress;

CustomFreeLibraryFunc freeLibrary;

struct ExportNameEntry* nameExportsTable;

void* userdata;

ExeEntryProc exeEntry;

DWORD pageSize;

#ifdef _WIN64

POINTER_LIST* blockedMemory;

} MEMORYMODULE, * PMEMORYMODULE;

typedef struct {

LPVOID address;

LPVOID alignedAddress;

SIZE_T size;

DWORD characteristics;

BOOL last;

} SECTIONFINALIZEDATA, * PSECTIONFINALIZEDATA;

#define GET_HEADER_DICTIONARY(module, idx) &(module)->headers->OptionalHeader.DataDirectory[idx]

static inline uintptr_t

AlignValueDown(uintptr_t value, uintptr_t alignment) {

return value & ~(alignment - 1);

}

static inline LPVOID

AlignAddressDown(LPVOID address, uintptr_t alignment) {

return (LPVOID)AlignValueDown((uintptr_t)address, alignment);

}

static inline size_t

AlignValueUp(size_t value, size_t alignment) {

return (value + alignment - 1) & ~(alignment - 1);

}

static inline void*

OffsetPointer(void* data, ptrdiff_t offset) {

return (void*)((uintptr_t)data + offset);

}

static inline void

OutputLastError(const char* msg)

{

#ifndef DEBUG_OUTPUT

UNREFERENCED_PARAMETER(msg);

LPVOID tmp;

char* tmpmsg;

FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,

NULL, GetLastError(), MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), (LPTSTR)&tmp, 0, NULL);

tmpmsg = (char*)LocalAlloc(LPTR, strlen(msg) + strlen(tmp) + 3);

sprintf(tmpmsg, "%s: %s", msg, tmp);

OutputDebugString(tmpmsg);

LocalFree(tmpmsg);

LocalFree(tmp);

}

#ifdef _WIN64

static void

FreePointerList(POINTER_LIST* head, CustomFreeFunc freeMemory, void* userdata)

{

POINTER_LIST* node = head;

while (node) {

POINTER_LIST* next;

freeMemory(node->address, 0, MEM_RELEASE, userdata);

next = node->next;

free(node);

node = next;

}

}

static BOOL

CheckSize(size_t size, size_t expected) {

if (size < expected) {

SetLastError(ERROR_INVALID_DATA);

return FALSE;

}

return TRUE;

}

static BOOL

CopySections(const unsigned char* data, size_t size, PIMAGE_NT_HEADERS old_headers, PMEMORYMODULE module)

{

int i, section_size;

unsigned char* codeBase = module->codeBase;

unsigned char* dest;

PIMAGE_SECTION_HEADER section = IMAGE_FIRST_SECTION(module->headers);

for (i = 0; i < module->headers->FileHeader.NumberOfSections; i++, section++) {

if (section->SizeOfRawData == 0) {

// section doesn't contain data in the dll itself, but may define

// uninitialized data

section_size = old_headers->OptionalHeader.SectionAlignment;

if (section_size > 0) {

dest = (unsigned char*)module->alloc(codeBase + section->VirtualAddress,

section_size,

MEM_COMMIT,

PAGE_READWRITE,

module->userdata);

if (dest == NULL) {

return FALSE;

}

// Always use position from file to support alignments smaller

// than page size (allocation above will align to page size).

dest = codeBase + section->VirtualAddress;

// NOTE: On 64bit systems we truncate to 32bit here but expand

// again later when "PhysicalAddress" is used.

section->Misc.PhysicalAddress = (DWORD)((uintptr_t)dest & 0xffffffff);

memset(dest, 0, section_size);

}

// section is empty

continue;

}

if (!CheckSize(size, section->PointerToRawData + section->SizeOfRawData)) {

return FALSE;

}

// commit memory block and copy data from dll

dest = (unsigned char*)module->alloc(codeBase + section->VirtualAddress,

section->SizeOfRawData,

MEM_COMMIT,

PAGE_READWRITE,

module->userdata);

if (dest == NULL) {

return FALSE;

}

// Always use position from file to support alignments smaller

// than page size (allocation above will align to page size).

dest = codeBase + section->VirtualAddress;

memcpy(dest, data + section->PointerToRawData, section->SizeOfRawData);

// NOTE: On 64bit systems we truncate to 32bit here but expand

// again later when "PhysicalAddress" is used.

section->Misc.PhysicalAddress = (DWORD)((uintptr_t)dest & 0xffffffff);

}

return TRUE;

}

static int ProtectionFlags[2][2][2] = {

{

// not executable

{PAGE_NOACCESS, PAGE_WRITECOPY},

{PAGE_READONLY, PAGE_READWRITE},

}, {

// executable

{PAGE_EXECUTE, PAGE_EXECUTE_WRITECOPY},

{PAGE_EXECUTE_READ, PAGE_EXECUTE_READWRITE},

},

};

static SIZE_T

GetRealSectionSize(PMEMORYMODULE module, PIMAGE_SECTION_HEADER section) {

DWORD size = section->SizeOfRawData;

if (size == 0) {

if (section->Characteristics & IMAGE_SCN_CNT_INITIALIZED_DATA) {

size = module->headers->OptionalHeader.SizeOfInitializedData;

}

else if (section->Characteristics & IMAGE_SCN_CNT_UNINITIALIZED_DATA) {

size = module->headers->OptionalHeader.SizeOfUninitializedData;

}

}

return (SIZE_T)size;

}

static BOOL

FinalizeSection(PMEMORYMODULE module, PSECTIONFINALIZEDATA sectionData) {

DWORD protect, oldProtect;

BOOL executable;

BOOL readable;

BOOL writeable;

if (sectionData->size == 0) {

return TRUE;

}

if (sectionData->characteristics & IMAGE_SCN_MEM_DISCARDABLE) {

// section is not needed any more and can safely be freed

if (sectionData->address == sectionData->alignedAddress &&

(sectionData->last ||

module->headers->OptionalHeader.SectionAlignment == module->pageSize ||

(sectionData->size % module->pageSize) == 0)

) {

// Only allowed to decommit whole pages

module->free(sectionData->address, sectionData->size, MEM_DECOMMIT, module->userdata);

}

return TRUE;

}

// determine protection flags based on characteristics

executable = (sectionData->characteristics & IMAGE_SCN_MEM_EXECUTE) != 0;

readable = (sectionData->characteristics & IMAGE_SCN_MEM_READ) != 0;

writeable = (sectionData->characteristics & IMAGE_SCN_MEM_WRITE) != 0;

protect = ProtectionFlags[executable][readable][writeable];

if (sectionData->characteristics & IMAGE_SCN_MEM_NOT_CACHED) {

protect |= PAGE_NOCACHE;

}

// change memory access flags

if (VirtualProtect(sectionData->address, sectionData->size, protect, &oldProtect) == 0) {

OutputLastError("Error protecting memory page");

return FALSE;

}

return TRUE;

}

static BOOL

FinalizeSections(PMEMORYMODULE module)

{

int i;

PIMAGE_SECTION_HEADER section = IMAGE_FIRST_SECTION(module->headers);

#ifdef _WIN64

// "PhysicalAddress" might have been truncated to 32bit above, expand to

// 64bits again.

uintptr_t imageOffset = ((uintptr_t)module->headers->OptionalHeader.ImageBase & 0xffffffff00000000);

static const uintptr_t imageOffset = 0;

SECTIONFINALIZEDATA sectionData;

sectionData.address = (LPVOID)((uintptr_t)section->Misc.PhysicalAddress | imageOffset);

sectionData.alignedAddress = AlignAddressDown(sectionData.address, module->pageSize);

sectionData.size = GetRealSectionSize(module, section);

sectionData.characteristics = section->Characteristics;

sectionData.last = FALSE;

section++;

// loop through all sections and change access flags

for (i = 1; i < module->headers->FileHeader.NumberOfSections; i++, section++) {

LPVOID sectionAddress = (LPVOID)((uintptr_t)section->Misc.PhysicalAddress | imageOffset);

LPVOID alignedAddress = AlignAddressDown(sectionAddress, module->pageSize);

SIZE_T sectionSize = GetRealSectionSize(module, section);

// Combine access flags of all sections that share a page

// TODO(fancycode): We currently share flags of a trailing large section

// with the page of a first small section. This should be optimized.

if (sectionData.alignedAddress == alignedAddress || (uintptr_t)sectionData.address + sectionData.size > (uintptr_t)alignedAddress) {

// Section shares page with previous

if ((section->Characteristics & IMAGE_SCN_MEM_DISCARDABLE) == 0 || (sectionData.characteristics & IMAGE_SCN_MEM_DISCARDABLE) == 0) {

sectionData.characteristics = (sectionData.characteristics | section->Characteristics) & ~IMAGE_SCN_MEM_DISCARDABLE;

}

else {

sectionData.characteristics |= section->Characteristics;

}

sectionData.size = (((uintptr_t)sectionAddress) + ((uintptr_t)sectionSize)) - (uintptr_t)sectionData.address;

continue;

}

if (!FinalizeSection(module, &sectionData)) {

return FALSE;

}

sectionData.address = sectionAddress;

sectionData.alignedAddress = alignedAddress;

sectionData.size = sectionSize;

sectionData.characteristics = section->Characteristics;

}

sectionData.last = TRUE;

if (!FinalizeSection(module, &sectionData)) {

return FALSE;

}

return TRUE;

}

static BOOL

ExecuteTLS(PMEMORYMODULE module)

{

unsigned char* codeBase = module->codeBase;

PIMAGE_TLS_DIRECTORY tls;

PIMAGE_TLS_CALLBACK* callback;

PIMAGE_DATA_DIRECTORY directory = GET_HEADER_DICTIONARY(module, IMAGE_DIRECTORY_ENTRY_TLS);

if (directory->VirtualAddress == 0) {

return TRUE;

}

tls = (PIMAGE_TLS_DIRECTORY)(codeBase + directory->VirtualAddress);

callback = (PIMAGE_TLS_CALLBACK*)tls->AddressOfCallBacks;

if (callback) {

while (*callback) {

(*callback)((LPVOID)codeBase, DLL_PROCESS_ATTACH, NULL);

callback++;

}

}

return TRUE;

}

static BOOL

PerformBaseRelocation(PMEMORYMODULE module, ptrdiff_t delta)

{

unsigned char* codeBase = module->codeBase;

DWORD relocation_size;

PIMAGE_BASE_RELOCATION relocation;

PIMAGE_DATA_DIRECTORY directory = GET_HEADER_DICTIONARY(module, IMAGE_DIRECTORY_ENTRY_BASERELOC);

if (directory->Size == 0) {

return (delta == 0);

}

relocation_size = directory->Size;

relocation = (PIMAGE_BASE_RELOCATION)(codeBase + directory->VirtualAddress);

for (; relocation_size;) {

DWORD i;

unsigned char* dest = codeBase + relocation->VirtualAddress;

unsigned short* relInfo = (unsigned short*)OffsetPointer(relocation, IMAGE_SIZEOF_BASE_RELOCATION);

relocation_size -= relocation->SizeOfBlock;

for (i = 0; i < ((relocation->SizeOfBlock - IMAGE_SIZEOF_BASE_RELOCATION) / 2); i++, relInfo++) {

// the upper 4 bits define the type of relocation

int type = *relInfo >> 12;

// the lower 12 bits define the offset

int offset = *relInfo & 0xfff;

switch (type)

{

case IMAGE_REL_BASED_ABSOLUTE:

// skip relocation

break;

case IMAGE_REL_BASED_HIGHLOW:

// change complete 32 bit address

{

DWORD* patchAddrHL = (DWORD*)(dest + offset);

*patchAddrHL += (DWORD)delta;

}

break;

#ifdef _WIN64

case IMAGE_REL_BASED_DIR64:

{

ULONGLONG* patchAddr64 = (ULONGLONG*)(dest + offset);

*patchAddr64 += (ULONGLONG)delta;

}

break;

default:

//printf("Unknown relocation: %d\n", type);

break;

}

}

// advance to next relocation block

relocation = (PIMAGE_BASE_RELOCATION)OffsetPointer(relocation, relocation->SizeOfBlock);

}

return TRUE;

}

#include <iostream>

static BOOL

BuildImportTable(PMEMORYMODULE module)

{

unsigned char* codeBase = module->codeBase;

PIMAGE_IMPORT_DESCRIPTOR importDesc;

BOOL result = TRUE;

PIMAGE_DATA_DIRECTORY directory = GET_HEADER_DICTIONARY(module, IMAGE_DIRECTORY_ENTRY_IMPORT);

if (directory->Size == 0) {

return TRUE;

}

importDesc = (PIMAGE_IMPORT_DESCRIPTOR)(codeBase + directory->VirtualAddress);

for (; !IsBadReadPtr(importDesc, sizeof(IMAGE_IMPORT_DESCRIPTOR)) && importDesc->Name; importDesc++) {

uintptr_t* thunkRef;

FARPROC* funcRef;

HCUSTOMMODULE* tmp;

HCUSTOMMODULE handle = module->loadLibrary((LPCSTR)(codeBase + importDesc->Name), module->userdata);

if (handle == NULL) {

SetLastError(ERROR_MOD_NOT_FOUND);

result = FALSE;

break;

}

if (module->modules == NULL) {

tmp = (HCUSTOMMODULE*)HeapAlloc(GetProcessHeap(), HEAP_FREE_CHECKING_ENABLED, (module->numModules + 1) * sizeof(HCUSTOMMODULE));

}

else {

tmp = (HCUSTOMMODULE*)HeapReAlloc(GetProcessHeap(), HEAP_FREE_CHECKING_ENABLED, module->modules, (module->numModules + 1) * sizeof(HCUSTOMMODULE));

}

if (tmp == NULL) {

module->freeLibrary(handle, module->userdata);

SetLastError(ERROR_OUTOFMEMORY);

result = FALSE;

break;

}

module->modules = tmp;

module->modules[module->numModules++] = handle;

if (importDesc->OriginalFirstThunk) {

thunkRef = (uintptr_t*)(codeBase + importDesc->OriginalFirstThunk);

funcRef = (FARPROC*)(codeBase + importDesc->FirstThunk);

}

else {

// no hint table

thunkRef = (uintptr_t*)(codeBase + importDesc->FirstThunk);

funcRef = (FARPROC*)(codeBase + importDesc->FirstThunk);

}

for (; *thunkRef; thunkRef++, funcRef++) {

if (IMAGE_SNAP_BY_ORDINAL(*thunkRef)) {

*funcRef = module->getProcAddress(handle, (LPCSTR)IMAGE_ORDINAL(*thunkRef), module->userdata);

}

else {

PIMAGE_IMPORT_BY_NAME thunkData = (PIMAGE_IMPORT_BY_NAME)(codeBase + (*thunkRef));

*funcRef = module->getProcAddress(handle, (LPCSTR)&thunkData->Name, module->userdata);

}

if (*funcRef == 0) {

result = FALSE;

break;

}

}

if (!result) {

module->freeLibrary(handle, module->userdata);

SetLastError(ERROR_PROC_NOT_FOUND);

break;

}

}

return result;

}

LPVOID MemoryDefaultAlloc(LPVOID address, SIZE_T size, DWORD allocationType, DWORD protect, void* userdata)

{

UNREFERENCED_PARAMETER(userdata);

return VirtualAlloc(address, size, allocationType, protect);

}

BOOL MemoryDefaultFree(LPVOID lpAddress, SIZE_T dwSize, DWORD dwFreeType, void* userdata)

{

UNREFERENCED_PARAMETER(userdata);

return VirtualFree(lpAddress, dwSize, dwFreeType);

}

HCUSTOMMODULE MemoryDefaultLoadLibrary(LPCSTR filename, void* userdata)

{

HMODULE result;

UNREFERENCED_PARAMETER(userdata);

result = LoadLibraryA(filename);

if (result == NULL) {

return NULL;

}

return (HCUSTOMMODULE)result;

}

FARPROC MemoryDefaultGetProcAddress(HCUSTOMMODULE module, LPCSTR name, void* userdata)

{

UNREFERENCED_PARAMETER(userdata);

return (FARPROC)GetProcAddress((HMODULE)module, name);

}

void MemoryDefaultFreeLibrary(HCUSTOMMODULE module, void* userdata)

{

UNREFERENCED_PARAMETER(userdata);

FreeLibrary((HMODULE)module);

}

HMEMORYMODULE MemoryLoadLibrary(const void* data, size_t size)

{

return MemoryLoadLibraryEx(data, size, MemoryDefaultAlloc, MemoryDefaultFree, MemoryDefaultLoadLibrary, MemoryDefaultGetProcAddress, MemoryDefaultFreeLibrary, NULL);

}

HMEMORYMODULE MemoryLoadLibraryEx(const void* data, size_t size,

void* userdata)

{

PMEMORYMODULE result = NULL;

PIMAGE_DOS_HEADER dos_header;

PIMAGE_NT_HEADERS old_header;

unsigned char* code, * headers;

ptrdiff_t locationDelta;

SYSTEM_INFO sysInfo;

PIMAGE_SECTION_HEADER section;

DWORD i;

size_t optionalSectionSize;

size_t lastSectionEnd = 0;

size_t alignedImageSize;

#ifdef _WIN64

POINTER_LIST* blockedMemory = NULL;

if (!CheckSize(size, sizeof(IMAGE_DOS_HEADER))) {

return NULL;

}

dos_header = (PIMAGE_DOS_HEADER)data;

if (dos_header->e_magic != IMAGE_DOS_SIGNATURE) {

SetLastError(ERROR_BAD_EXE_FORMAT);

return NULL;

}

if (!CheckSize(size, dos_header->e_lfanew + sizeof(IMAGE_NT_HEADERS))) {

return NULL;

}

old_header = (PIMAGE_NT_HEADERS) & ((const unsigned char*)(data))[dos_header->e_lfanew];

if (old_header->Signature != IMAGE_NT_SIGNATURE) {

SetLastError(ERROR_BAD_EXE_FORMAT);

return NULL;

}

if (old_header->FileHeader.Machine != HOST_MACHINE) {

SetLastError(ERROR_BAD_EXE_FORMAT);

return NULL;

}

if (old_header->OptionalHeader.SectionAlignment & 1) {

// Only support section alignments that are a multiple of 2

SetLastError(ERROR_BAD_EXE_FORMAT);

return NULL;

}

section = IMAGE_FIRST_SECTION(old_header);

optionalSectionSize = old_header->OptionalHeader.SectionAlignment;

for (i = 0; i < old_header->FileHeader.NumberOfSections; i++, section++) {

size_t endOfSection;

if (section->SizeOfRawData == 0) {

// Section without data in the DLL

endOfSection = section->VirtualAddress + optionalSectionSize;

}

else {

endOfSection = section->VirtualAddress + section->SizeOfRawData;

}

if (endOfSection > lastSectionEnd) {

lastSectionEnd = endOfSection;

}

}

GetNativeSystemInfo(&sysInfo);

alignedImageSize = AlignValueUp(old_header->OptionalHeader.SizeOfImage, sysInfo.dwPageSize);

if (alignedImageSize != AlignValueUp(lastSectionEnd, sysInfo.dwPageSize)) {

SetLastError(ERROR_BAD_EXE_FORMAT);

return NULL;

}

// reserve memory for image of library

// XXX: is it correct to commit the complete memory region at once?

// calling DllEntry raises an exception if we don't...

code = (unsigned char*)allocMemory((LPVOID)(old_header->OptionalHeader.ImageBase),

alignedImageSize,

MEM_RESERVE | MEM_COMMIT,

PAGE_READWRITE,

userdata);

if (code == NULL) {

// try to allocate memory at arbitrary position

code = (unsigned char*)allocMemory(NULL,

alignedImageSize,

MEM_RESERVE | MEM_COMMIT,

PAGE_READWRITE,

userdata);

if (code == NULL) {

SetLastError(ERROR_OUTOFMEMORY);

return NULL;

}

}

#ifdef _WIN64

// Memory block may not span 4 GB boundaries.

while ((((uintptr_t)code) >> 32) < (((uintptr_t)(code + alignedImageSize)) >> 32)) {

POINTER_LIST* node = (POINTER_LIST*)malloc(sizeof(POINTER_LIST));

if (!node) {

freeMemory(code, 0, MEM_RELEASE, userdata);

FreePointerList(blockedMemory, freeMemory, userdata);

SetLastError(ERROR_OUTOFMEMORY);

return NULL;

}

node->next = blockedMemory;

node->address = code;

blockedMemory = node;

code = (unsigned char*)allocMemory(NULL,

alignedImageSize,

MEM_RESERVE | MEM_COMMIT,

PAGE_READWRITE,

userdata);

if (code == NULL) {

FreePointerList(blockedMemory, freeMemory, userdata);

SetLastError(ERROR_OUTOFMEMORY);

return NULL;

}

}

result = (PMEMORYMODULE)HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(MEMORYMODULE));

if (result == NULL) {

freeMemory(code, 0, MEM_RELEASE, userdata);

#ifdef _WIN64

FreePointerList(blockedMemory, freeMemory, userdata);

SetLastError(ERROR_OUTOFMEMORY);

return NULL;

}

result->codeBase = code;

result->isDLL = (old_header->FileHeader.Characteristics & IMAGE_FILE_DLL) != 0;

result->alloc = allocMemory;

result->free = freeMemory;

result->loadLibrary = loadLibrary;

result->getProcAddress = getProcAddress;

result->freeLibrary = freeLibrary;

result->userdata = userdata;

result->pageSize = sysInfo.dwPageSize;

result->modules = NULL;

result->numModules = 0;

#ifdef _WIN64

result->blockedMemory = blockedMemory;

if (!CheckSize(size, old_header->OptionalHeader.SizeOfHeaders)) {

goto error;

}

// commit memory for headers

headers = (unsigned char*)allocMemory(code,

old_header->OptionalHeader.SizeOfHeaders,

MEM_COMMIT,

PAGE_READWRITE,

userdata);

// copy PE header to code

memcpy(headers, dos_header, old_header->OptionalHeader.SizeOfHeaders);

result->headers = (PIMAGE_NT_HEADERS) & ((const unsigned char*)(headers))[dos_header->e_lfanew];

// update position

result->headers->OptionalHeader.ImageBase = (uintptr_t)code;

// copy sections from DLL file block to new memory location

if (!CopySections((const unsigned char*)data, size, old_header, result)) {

goto error;

}

// adjust base address of imported data

locationDelta = (ptrdiff_t)(result->headers->OptionalHeader.ImageBase - old_header->OptionalHeader.ImageBase);

if (locationDelta != 0) {

result->isRelocated = PerformBaseRelocation(result, locationDelta);

}

else {

result->isRelocated = TRUE;

}

// load required dlls and adjust function table of imports

if (!BuildImportTable(result)) {

goto error;

}

// mark memory pages depending on section headers and release

// sections that are marked as "discardable"

if (!FinalizeSections(result)) {

goto error;

}

// TLS callbacks are executed BEFORE the main loading

if (!ExecuteTLS(result)) {

goto error;

}

// get entry point of loaded library

if (result->headers->OptionalHeader.AddressOfEntryPoint != 0) {

if (result->isDLL) {

DllEntryProc DllEntry = (DllEntryProc)(LPVOID)(code + result->headers->OptionalHeader.AddressOfEntryPoint);

// notify library about attaching to process

BOOL successfull = (*DllEntry)((HINSTANCE)code, DLL_PROCESS_ATTACH, 0);

if (!successfull) {

SetLastError(ERROR_DLL_INIT_FAILED);

goto error;

}

result->initialized = TRUE;

}

else {

result->exeEntry = (ExeEntryProc)(LPVOID)(code + result->headers->OptionalHeader.AddressOfEntryPoint);

}

}

else {

result->exeEntry = NULL;

}

return (HMEMORYMODULE)result;

error:

// cleanup

MemoryFreeLibrary(result);

return NULL;

}

static int _compare(const void* a, const void* b)

{

const struct ExportNameEntry* p1 = (const struct ExportNameEntry*)a;

const struct ExportNameEntry* p2 = (const struct ExportNameEntry*)b;

return strcmp(p1->name, p2->name);

}

static int _find(const void* a, const void* b)

{

LPCSTR* name = (LPCSTR*)a;

const struct ExportNameEntry* p = (const struct ExportNameEntry*)b;

return strcmp(*name, p->name);

}

FARPROC MemoryGetProcAddress(HMEMORYMODULE mod, LPCSTR name)

{

PMEMORYMODULE module = (PMEMORYMODULE)mod;

unsigned char* codeBase = module->codeBase;

DWORD idx = 0;

PIMAGE_EXPORT_DIRECTORY exports;

PIMAGE_DATA_DIRECTORY directory = GET_HEADER_DICTIONARY(module, IMAGE_DIRECTORY_ENTRY_EXPORT);

if (directory->Size == 0) {

// no export table found

SetLastError(ERROR_PROC_NOT_FOUND);

return NULL;

}

exports = (PIMAGE_EXPORT_DIRECTORY)(codeBase + directory->VirtualAddress);

if (exports->NumberOfNames == 0 || exports->NumberOfFunctions == 0) {

// DLL doesn't export anything

SetLastError(ERROR_PROC_NOT_FOUND);

return NULL;

}

if (HIWORD(name) == 0) {

// load function by ordinal value

if (LOWORD(name) < exports->Base) {

SetLastError(ERROR_PROC_NOT_FOUND);

return NULL;

}

idx = LOWORD(name) - exports->Base;

}

else if (!exports->NumberOfNames) {

SetLastError(ERROR_PROC_NOT_FOUND);

return NULL;

}

else {

const struct ExportNameEntry* found;

// Lazily build name table and sort it by names

if (!module->nameExportsTable) {

DWORD i;

DWORD* nameRef = (DWORD*)(codeBase + exports->AddressOfNames);

WORD* ordinal = (WORD*)(codeBase + exports->AddressOfNameOrdinals);

struct ExportNameEntry* entry = (struct ExportNameEntry*)HeapAlloc(GetProcessHeap(), HEAP_FREE_CHECKING_ENABLED, exports->NumberOfNames * sizeof(struct ExportNameEntry));

module->nameExportsTable = entry;

if (!entry) {

SetLastError(ERROR_OUTOFMEMORY);

return NULL;

}

for (i = 0; i < exports->NumberOfNames; i++, nameRef++, ordinal++, entry++) {

entry->name = (const char*)(codeBase + (*nameRef));

entry->idx = *ordinal;

}

qsort(module->nameExportsTable,

exports->NumberOfNames,

sizeof(struct ExportNameEntry), _compare);

}

// search function name in list of exported names with binary search

found = (const struct ExportNameEntry*)bsearch(&name,

module->nameExportsTable,

exports->NumberOfNames,

sizeof(struct ExportNameEntry), _find);

if (!found) {

// exported symbol not found

SetLastError(ERROR_PROC_NOT_FOUND);

return NULL;

}

idx = found->idx;

}

if (idx > exports->NumberOfFunctions) {

// name <-> ordinal number don't match

SetLastError(ERROR_PROC_NOT_FOUND);

return NULL;

}

// AddressOfFunctions contains the RVAs to the "real" functions

return (FARPROC)(LPVOID)(codeBase + (*(DWORD*)(codeBase + exports->AddressOfFunctions + (idx * 4))));

}

void MemoryFreeLibrary(HMEMORYMODULE mod)

{

PMEMORYMODULE module = (PMEMORYMODULE)mod;

if (module == NULL) {

return;

}

if (module->initialized) {

// notify library about detaching from process

DllEntryProc DllEntry = (DllEntryProc)(LPVOID)(module->codeBase + module->headers->OptionalHeader.AddressOfEntryPoint);

(*DllEntry)((HINSTANCE)module->codeBase, DLL_PROCESS_DETACH, 0);

}

HeapFree(GetProcessHeap(), HEAP_FREE_CHECKING_ENABLED, module->nameExportsTable);

if (module->modules != NULL) {

// free previously opened libraries

int i;

for (i = 0; i < module->numModules; i++) {

if (module->modules[i] != NULL) {

module->freeLibrary(module->modules[i], module->userdata);

}

}

if (module->modules != NULL) {

HeapFree(GetProcessHeap(), HEAP_FREE_CHECKING_ENABLED, module->modules);

}

}

if (module->codeBase != NULL) {

// release memory of library

module->free(module->codeBase, 0, MEM_RELEASE, module->userdata);

}

#ifdef _WIN64

FreePointerList(module->blockedMemory, module->free, module->userdata);

HeapFree(GetProcessHeap(), 0, module);

}

int MemoryCallEntryPoint(HMEMORYMODULE mod)

{

PMEMORYMODULE module = (PMEMORYMODULE)mod;

if (module == NULL || module->isDLL || module->exeEntry == NULL || !module->isRelocated) {

return -1;

}

return module->exeEntry();

}

#define DEFAULT_LANGUAGE MAKELANGID(LANG_NEUTRAL, SUBLANG_NEUTRAL)

HMEMORYRSRC MemoryFindResource(HMEMORYMODULE module, LPCTSTR name, LPCTSTR type)

{

return MemoryFindResourceEx(module, name, type, DEFAULT_LANGUAGE);

}

static PIMAGE_RESOURCE_DIRECTORY_ENTRY _MemorySearchResourceEntry(

void* root,

PIMAGE_RESOURCE_DIRECTORY resources,

LPCTSTR key)

{

PIMAGE_RESOURCE_DIRECTORY_ENTRY entries = (PIMAGE_RESOURCE_DIRECTORY_ENTRY)(resources + 1);

PIMAGE_RESOURCE_DIRECTORY_ENTRY result = NULL;

DWORD start;

DWORD end;

DWORD middle;

if (!IS_INTRESOURCE(key) && key[0] == TEXT('#')) {

// special case: resource id given as string

TCHAR* endpos = NULL;

long int tmpkey = (WORD)_tcstol((TCHAR*)&key[1], &endpos, 10);

if (tmpkey <= 0xffff && lstrlen(endpos) == 0) {

key = MAKEINTRESOURCE(tmpkey);

}

}

// entries are stored as ordered list of named entries,

// followed by an ordered list of id entries - we can do

// a binary search to find faster...

if (IS_INTRESOURCE(key)) {

WORD check = (WORD)(uintptr_t)key;

start = resources->NumberOfNamedEntries;

end = start + resources->NumberOfIdEntries;

while (end > start) {

WORD entryName;

middle = (start + end) >> 1;

entryName = (WORD)entries[middle].Name;

if (check < entryName) {

end = (end != middle ? middle : middle - 1);

}

else if (check > entryName) {

start = (start != middle ? middle : middle + 1);

}

else {

result = &entries[middle];

break;

}

}

}

else {

LPCWSTR searchKey;

size_t searchKeyLen = _tcslen(key);

#if defined(UNICODE)

searchKey = key;

// Resource names are always stored using 16bit characters, need to

// convert string we search for.

#define MAX_LOCAL_KEY_LENGTH 2048

// In most cases resource names are short, so optimize for that by

// using a pre-allocated array.

wchar_t _searchKeySpace[MAX_LOCAL_KEY_LENGTH + 1];

LPWSTR _searchKey;

if (searchKeyLen > MAX_LOCAL_KEY_LENGTH) {

size_t _searchKeySize = (searchKeyLen + 1) * sizeof(wchar_t);

_searchKey = (LPWSTR)malloc(_searchKeySize);

if (_searchKey == NULL) {

SetLastError(ERROR_OUTOFMEMORY);

return NULL;

}

}

else {