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Fix Ldrp finder #62

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Merged
bb107 merged 2 commits into from
Feb 11, 2025
Merged

Fix Ldrp finder #62

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36a4377
Fix Ldrp finder
kotori2 Feb 2, 2025
4ae15d8
Search by 4 bytes
kotori2 Feb 7, 2025
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116 changes: 79 additions & 37 deletions MemoryModule/MmpLdrpTls.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -6,35 +6,13 @@ static bool stdcall;
static PVOID LdrpHandleTlsData;
static PVOID LdrpReleaseTlsEntry;

static NTSTATUS NTAPI RtlFindLdrpHandleTlsData() {
static NTSTATUS NTAPI RtlFindLdrpHandleTlsDataOld() {
NTSTATUS status = STATUS_SUCCESS;
LPCVOID Feature = nullptr;
BYTE Size = 0;
WORD OffsetOfFunctionBegin = 0;

switch (MmpGlobalDataPtr->NtVersions.MajorVersion) {
case 10: {
if (MmpGlobalDataPtr->NtVersions.MinorVersion)return STATUS_NOT_SUPPORTED;

if (MmpGlobalDataPtr->NtVersions.BuildNumber >= 22621) {
#ifdef _WIN64
Feature = "\x39\x1D\x23\xFC\x17\x00\x74\x37\x44\x8D\x43\x09\x44\x39\x81\x0C\x01\x00\x00\x74\x2A";
Size = 22;
OffsetOfFunctionBegin = 0x43;
#else
return STATUS_NOT_SUPPORTED;
#endif
}
//
// Add more conditions here.
//
// else if (MmpGlobalDataPtr->NtVersions.BuildNumber >= XXXXXXXXX)
else {
return STATUS_NOT_SUPPORTED;
}

break;
}
case 6: {
switch (MmpGlobalDataPtr->NtVersions.MinorVersion) {
//8.1
Expand Down Expand Up @@ -94,6 +72,81 @@ static NTSTATUS NTAPI RtlFindLdrpHandleTlsData() {
return status;
}

static NTSTATUS NTAPI RtlFindLdrpHandleTlsData10() {
LPVOID DllBase = MmpGlobalDataPtr->MmpBaseAddressIndex->NtdllLdrEntry->DllBase;
#ifdef _WIN64
// search for LdrpHandleTls string literal
SEARCH_CONTEXT SearchContext{ SearchContext.SearchPattern = LPBYTE("LdrpHandleTlsData\x00"), SearchContext.PatternSize = 18 };
if (!NT_SUCCESS(RtlFindMemoryBlockFromModuleSection(HMODULE(DllBase), ".rdata", &SearchContext)))
return STATUS_NOT_SUPPORTED;
LPBYTE StringOffset = SearchContext.Result;

SearchContext.Result = nullptr;
SearchContext.PatternSize = 3;
SearchContext.SearchPattern = LPBYTE("\x48\x8D\x15");
LPBYTE ExceptionBlock = nullptr;

// Search for lea rdx,[rip+0x????]
// ???? is the relative offset from RIP to LdrpHandleTls string literal
while (NT_SUCCESS(RtlFindMemoryBlockFromModuleSection(HMODULE(DllBase), ".text", &SearchContext))) {
DWORD InsOff = *(DWORD*)(SearchContext.Result + 3);
if (StringOffset == SearchContext.Result + InsOff + 7) {
ExceptionBlock = SearchContext.Result;
break;
}
}
if (!ExceptionBlock) return STATUS_NOT_SUPPORTED;

// Search back for exception block function header
while (*ExceptionBlock != 0xcc) {
// Normally ~13 bytes, but just in case...
if (SearchContext.Result - ExceptionBlock > 0x50) return STATUS_NOT_SUPPORTED;
ExceptionBlock--;
}
ExceptionBlock++;

// search for C_SCOPE_TABLE
union Converter {
BYTE Bytes[4];
DWORD Dword;
};
Converter ExceptionBlockAddress{ .Dword = DWORD(ExceptionBlock - LPBYTE(DllBase)) };
SearchContext.Result = nullptr;
SearchContext.PatternSize = 4;
SearchContext.SearchPattern = ExceptionBlockAddress.Bytes;
if (!NT_SUCCESS(RtlFindMemoryBlockFromModuleSection(HMODULE(DllBase), ".rdata", &SearchContext)))
return STATUS_NOT_SUPPORTED;

// C_SCOPE_TABLE$$Begin
LPDWORD LdrpHandleTlsBlock = LPDWORD(*(LPDWORD)(SearchContext.Result - 8) + LPBYTE(DllBase));
// Pad to 0x04
LdrpHandleTlsBlock = LPDWORD(LONGLONG(LdrpHandleTlsBlock) / 0x04 * 0x04);
LPDWORD LdrpHandleTlsBlockBackup = LdrpHandleTlsBlock;

// Search back for LdrpHandleTls
// Search up for 4 consecutive 0xCC
while (*LdrpHandleTlsBlock != 0xcccccccc) {
// Normally ~0x140 bytes
if (LdrpHandleTlsBlockBackup - LdrpHandleTlsBlock > 0x400) return STATUS_NOT_SUPPORTED;
LdrpHandleTlsBlock--;
}
LdrpHandleTlsBlock++;
LdrpHandleTlsData = LdrpHandleTlsDataBlock;
return STATUS_SUCCESS;
#else
return STATUS_NOT_SUPPORTED;
#endif
}

static NTSTATUS NTAPI RtlFindLdrpHandleTlsData() {
if (MmpGlobalDataPtr->NtVersions.MajorVersion >= 10) {
return RtlFindLdrpHandleTlsData10();
}
else {
return RtlFindLdrpHandleTlsDataOld();
}
}

static NTSTATUS NTAPI RtlFindLdrpReleaseTlsEntry() {
NTSTATUS status = STATUS_SUCCESS;
LPCVOID Feature = nullptr;
Expand All @@ -104,23 +157,12 @@ static NTSTATUS NTAPI RtlFindLdrpReleaseTlsEntry() {
case 10: {
if (MmpGlobalDataPtr->NtVersions.MinorVersion) return STATUS_NOT_SUPPORTED;

if (MmpGlobalDataPtr->NtVersions.BuildNumber >= 22621) {
#ifdef _WIN64
Feature = "\x74\x34\x48\x8B\x08\x48\x39\x41\x08\x75\x65\x48\x8B\x40\x08\x48\x39\x18\x75\x5C\x48\x89\x08";
Size = 24;
OffsetOfFunctionBegin = 0x2F;
Feature = "\x48\x89\x5c\x24\x08\x57\x48\x83\xec\x20\x48\x8b\xfa\x48\x8b\xd9\x48\x85\xd2\x75\x0c";
Size = 21;
#else
return STATUS_NOT_SUPPORTED;
return STATUS_NOT_SUPPORTED;
#endif
}
//
// Add more conditions here.
//
// else if (MmpGlobalDataPtr->NtVersions.BuildNumber >= XXXXXXXXX)
else {
return STATUS_NOT_SUPPORTED;
}

break;
}
default:
Expand Down