2021-01-30 12:45:37 -07:00

330 lines
10 KiB
C++

// texthook.cc
// 8/24/2013 jichi
// Branch: ITH_DLL/texthook.cpp, rev 128
// 8/24/2013 TODO: Clean up this file
#include "texthook.h"
#include "main.h"
#include "ithsys/ithsys.h"
extern const char* FUNC_MISSING;
extern const char* MODULE_MISSING;
extern const char* GARBAGE_MEMORY;
extern const char* SEND_ERROR;
extern const char* READ_ERROR;
extern WinMutex viewMutex;
// - Unnamed helpers -
namespace { // unnamed
#ifndef _WIN64
BYTE common_hook[] = {
0x9c, // pushfd
0x60, // pushad
0x9c, // pushfd ; Artikash 11/4/2018: not sure why pushfd happens twice. Anyway, after this a total of 0x28 bytes are pushed
0x8d, 0x44, 0x24, 0x28, // lea eax,[esp+0x28]
0x50, // push eax ; dwDatabase
0xb9, 0,0,0,0, // mov ecx,@this
0xbb, 0,0,0,0, // mov ebx,@TextHook::Send
0xff, 0xd3, // call ebx
0x9d, // popfd
0x61, // popad
0x9d, // popfd
0x68, 0,0,0,0, // push @original
0xc3 // ret ; basically absolute jmp to @original
};
int this_offset = 9, send_offset = 14, original_offset = 24;
#else
BYTE common_hook[] = {
0x9c, // push rflags
0x50, // push rax
0x53, // push rbx
0x51, // push rcx
0x52, // push rdx
0x54, // push rsp
0x55, // push rbp
0x56, // push rsi
0x57, // push rdi
0x41, 0x50, // push r8
0x41, 0x51, // push r9
0x41, 0x52, // push r10
0x41, 0x53, // push r11
0x41, 0x54, // push r12
0x41, 0x55, // push r13
0x41, 0x56, // push r14
0x41, 0x57, // push r15
// https://docs.microsoft.com/en-us/cpp/build/x64-calling-convention
// https://stackoverflow.com/questions/43358429/save-value-of-xmm-registers
0x48, 0x83, 0xec, 0x20, // sub rsp,0x20
0xf3, 0x0f, 0x7f, 0x24, 0x24, // movdqu [rsp],xmm4
0xf3, 0x0f, 0x7f, 0x6c, 0x24, 0x10, // movdqu [rsp+0x10],xmm5
0x48, 0x8d, 0x94, 0x24, 0xa8, 0x00, 0x00, 0x00, // lea rdx,[rsp+0xa8]
0x48, 0xb9, 0,0,0,0,0,0,0,0, // mov rcx,@this
0x48, 0xb8, 0,0,0,0,0,0,0,0, // mov rax,@TextHook::Send
0x48, 0x89, 0xe3, // mov rbx,rsp
0x48, 0x83, 0xe4, 0xf0, // and rsp,0xfffffffffffffff0 ; align stack
0xff, 0xd0, // call rax
0x48, 0x89, 0xdc, // mov rsp,rbx
0xf3, 0x0f, 0x6f, 0x6c, 0x24, 0x10, // movdqu xmm5,XMMWORD PTR[rsp + 0x10]
0xf3, 0x0f, 0x6f, 0x24, 0x24, // movdqu xmm4,XMMWORD PTR[rsp]
0x48, 0x83, 0xc4, 0x20, // add rsp,0x20
0x41, 0x5f, // pop r15
0x41, 0x5e, // pop r14
0x41, 0x5d, // pop r13
0x41, 0x5c, // pop r12
0x41, 0x5b, // pop r11
0x41, 0x5a, // pop r10
0x41, 0x59, // pop r9
0x41, 0x58, // pop r8
0x5f, // pop rdi
0x5e, // pop rsi
0x5d, // pop rbp
0x5c, // pop rsp
0x5a, // pop rdx
0x59, // pop rcx
0x5b, // pop rbx
0x58, // pop rax
0x9d, // pop rflags
0xff, 0x25, 0x00, 0x00, 0x00, 0x00, // jmp qword ptr [rip]
0,0,0,0,0,0,0,0 // @original
};
int this_offset = 50, send_offset = 60, original_offset = 126;
#endif
thread_local BYTE buffer[PIPE_BUFFER_SIZE];
enum { TEXT_BUFFER_SIZE = PIPE_BUFFER_SIZE - sizeof(ThreadParam) };
} // unnamed namespace
// - TextHook methods -
bool TextHook::Insert(HookParam hp, DWORD set_flag)
{
{
std::scoped_lock lock(viewMutex);
hp.type |= set_flag;
if (hp.type & USING_UTF8) hp.codepage = CP_UTF8;
this->hp = hp;
address = hp.address;
}
if (hp.type & DIRECT_READ) return InsertReadCode();
return InsertHookCode();
}
// jichi 5/11/2014:
// - dwDataBase: the stack address
void TextHook::Send(uintptr_t dwDataBase)
{
BYTE(*buffer)[PIPE_BUFFER_SIZE] = &::buffer, *pbData = *buffer + sizeof(ThreadParam);
_InterlockedIncrement(&useCount);
__try
{
if (auto current_trigger_fun = trigger_fun.exchange(nullptr))
if (!current_trigger_fun(location, *(DWORD*)(dwDataBase - 0x1c), *(DWORD*)(dwDataBase - 0x18))) trigger_fun = current_trigger_fun;
#ifndef _WIN64
DWORD dwCount = 0,
dwSplit = 0,
dwDataIn = *(DWORD*)(dwDataBase + hp.offset), // default values
dwRetn = *(DWORD*)dwDataBase; // first value on stack (if hooked start of function, this is return address)
// jichi 10/24/2014: generic hook function
if (hp.hook_fun && !hp.hook_fun(dwDataBase, &hp)) hp.hook_fun = nullptr;
if (hp.type & HOOK_EMPTY) goto done; // jichi 10/24/2014: dummy hook only for dynamic hook
if (hp.text_fun) {
hp.text_fun(dwDataBase, &hp, 0, &dwDataIn, &dwSplit, &dwCount);
}
else {
if (hp.type & FIXING_SPLIT) dwSplit = FIXED_SPLIT_VALUE; // fuse all threads, and prevent floating
else if (hp.type & USING_SPLIT) {
dwSplit = *(DWORD *)(dwDataBase + hp.split);
if (hp.type & SPLIT_INDIRECT) dwSplit = *(DWORD *)(dwSplit + hp.split_index);
}
if (hp.type & DATA_INDIRECT) dwDataIn = *(DWORD *)(dwDataIn + hp.index);
dwDataIn += hp.padding;
dwCount = GetLength(dwDataBase, dwDataIn);
}
if (dwCount <= 0) goto done;
if (dwCount > TEXT_BUFFER_SIZE) dwCount = TEXT_BUFFER_SIZE;
if (hp.length_offset == 1) {
dwDataIn &= 0xffff;
if ((hp.type & BIG_ENDIAN) && (dwDataIn >> 8)) dwDataIn = _byteswap_ushort(dwDataIn & 0xffff);
if (dwCount == 1) dwDataIn &= 0xff;
*(WORD*)pbData = dwDataIn & 0xffff;
}
else ::memcpy(pbData, (void*)dwDataIn, dwCount);
if (hp.filter_fun && !hp.filter_fun(pbData, &dwCount, &hp, 0) || dwCount <= 0) goto done;
if (hp.type & (NO_CONTEXT | FIXING_SPLIT)) dwRetn = 0;
TextOutput({ GetCurrentProcessId(), address, dwRetn, dwSplit }, buffer, dwCount);
#else // _WIN32
if (hp.type & HOOK_EMPTY) goto done; // jichi 10/24/2014: dummy hook only for dynamic hook
int count = 0;
ThreadParam tp = { GetCurrentProcessId(), address, *(uintptr_t*)dwDataBase, 0 }; // first value on stack (if hooked start of function, this is return address)
uintptr_t data = *(uintptr_t*)(dwDataBase + hp.offset); // default value
if (hp.type & USING_SPLIT)
{
tp.ctx2 = *(uintptr_t*)(dwDataBase + hp.split);
if (hp.type & SPLIT_INDIRECT) tp.ctx2 = *(uintptr_t*)(tp.ctx2 + hp.split_index);
}
if (hp.type & DATA_INDIRECT) data = *(uintptr_t*)(data + hp.index);
data += hp.padding;
count = GetLength(dwDataBase, data);
if (count <= 0) goto done;
if (count > TEXT_BUFFER_SIZE) count = TEXT_BUFFER_SIZE;
if (hp.length_offset == 1)
{
data &= 0xffff;
if ((hp.type & BIG_ENDIAN) && (data >> 8)) data = _byteswap_ushort(data & 0xffff);
if (count == 1) data &= 0xff;
*(WORD*)pbData = data & 0xffff;
}
else ::memcpy(pbData, (void*)data, count);
if (hp.type & (NO_CONTEXT | FIXING_SPLIT)) tp.ctx = 0;
TextOutput(tp, buffer, count);
#endif // _WIN64
}
__except (EXCEPTION_EXECUTE_HANDLER)
{
if (!err && !(hp.type & KNOWN_UNSTABLE))
{
err = true;
ConsoleOutput("%s in %s", SEND_ERROR, hp.name);
}
}
done:
_InterlockedDecrement(&useCount);
}
bool TextHook::InsertHookCode()
{
// jichi 9/17/2013: might raise 0xC0000005 AccessViolationException on win7
// Artikash 10/30/2018: No, I think that's impossible now that I moved to minhook
if (hp.type & MODULE_OFFSET) // Map hook offset to real address
if (hp.type & FUNCTION_OFFSET)
if (FARPROC function = GetProcAddress(GetModuleHandleW(hp.module), hp.function)) address += (uint64_t)function;
else return ConsoleOutput(FUNC_MISSING), false;
else if (HMODULE moduleBase = GetModuleHandleW(hp.module)) address += (uint64_t)moduleBase;
else return ConsoleOutput(MODULE_MISSING), false;
VirtualProtect(location, 10, PAGE_EXECUTE_READWRITE, DUMMY);
void* original;
MH_STATUS error;
while ((error = MH_CreateHook(location, trampoline, &original)) != MH_OK)
if (error == MH_ERROR_ALREADY_CREATED) RemoveHook(address);
else return ConsoleOutput(MH_StatusToString(error)), false;
*(TextHook**)(common_hook + this_offset) = this;
*(void(TextHook::**)(uintptr_t))(common_hook + send_offset) = &TextHook::Send;
*(void**)(common_hook + original_offset) = original;
memcpy(trampoline, common_hook, sizeof(common_hook));
return MH_EnableHook(location) == MH_OK;
}
void TextHook::Read()
{
int dataLen = 1;
BYTE(*buffer)[PIPE_BUFFER_SIZE] = &::buffer, *pbData = *buffer + sizeof(ThreadParam);
__try
{
while (WaitForSingleObject(readerEvent, 500) == WAIT_TIMEOUT) if (memcmp(pbData, location, dataLen) != 0) if (int currentLen = HookStrlen((BYTE*)location))
{
dataLen = min(currentLen, TEXT_BUFFER_SIZE);
memcpy(pbData, location, dataLen);
TextOutput({ GetCurrentProcessId(), address, 0, 0 }, buffer, dataLen);
}
}
__except (EXCEPTION_EXECUTE_HANDLER)
{
ConsoleOutput("%s in %s", READ_ERROR, hp.name);
Clear();
}
}
bool TextHook::InsertReadCode()
{
readerThread = CreateThread(nullptr, 0, [](void* This) { ((TextHook*)This)->Read(); return 0UL; }, this, 0, nullptr);
readerEvent = CreateEventW(nullptr, FALSE, FALSE, NULL);
return true;
}
void TextHook::RemoveHookCode()
{
MH_DisableHook(location);
while (useCount != 0);
MH_RemoveHook(location);
}
void TextHook::RemoveReadCode()
{
SetEvent(readerEvent);
if (GetThreadId(readerThread) != GetCurrentThreadId()) WaitForSingleObject(readerThread, 1000);
CloseHandle(readerEvent);
CloseHandle(readerThread);
}
void TextHook::Clear()
{
if (address == 0) return;
if (hp.type & DIRECT_READ) RemoveReadCode();
else RemoveHookCode();
NotifyHookRemove(address, hp.name);
std::scoped_lock lock(viewMutex);
memset(&hp, 0, sizeof(HookParam));
address = 0;
}
int TextHook::GetLength(uintptr_t base, uintptr_t in)
{
int len;
if (hp.length_fun) return hp.length_fun(base, in);
switch (hp.length_offset) {
default: // jichi 12/26/2013: I should not put this default branch to the end
len = *((uintptr_t*)base + hp.length_offset);
if (len >= 0) {
if (hp.type & USING_UNICODE)
len <<= 1;
break;
}
else if (len != -1)
break;
//len == -1 then continue to case 0.
case 0:
len = HookStrlen((BYTE*)in);
break;
case 1:
if (hp.type & USING_UNICODE)
len = 2;
else {
if (hp.type & BIG_ENDIAN)
in >>= 8;
len = LeadByteTable[in & 0xff]; //Slightly faster than IsDBCSLeadByte
}
break;
}
// jichi 12/25/2013: This function originally return -1 if failed
//return len;
return max(0, len);
}
int TextHook::HookStrlen(BYTE* data)
{
if (!hp.null_length) return hp.type & USING_UNICODE ? wcslen((wchar_t*)data) * 2 : strlen((char*)data);
BYTE* orig = data;
for (int nullsRemaining = hp.null_length; nullsRemaining > 0; ++data)
if (*data == 0) nullsRemaining -= 1;
else nullsRemaining = hp.null_length;
return data - orig;
}
// EOF