diff options
| -rw-r--r-- | MemDriverLib/DLLHelper.cpp | 50 | ||||
| -rw-r--r-- | include/DLLHelper.h | 1 |
2 files changed, 51 insertions, 0 deletions
diff --git a/MemDriverLib/DLLHelper.cpp b/MemDriverLib/DLLHelper.cpp index 78fdf83..0688434 100644 --- a/MemDriverLib/DLLHelper.cpp +++ b/MemDriverLib/DLLHelper.cpp @@ -233,4 +233,54 @@ bool DLLHelper::FixImports() } return true; +} + +bool DLLHelper::FixRelocs() +{ + unsigned long long ImageBase; + unsigned int nBytes = 0; + unsigned long delta; + IMAGE_BASE_RELOCATION *reloc; + + if (!m_TargetPID || !m_TargetBaseAddress || !m_NTHeader || + !m_NTHeader->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_BASERELOC].Size) + { + std::stringstream err_str; + err_str << "Pre-requirement failed (PID: " << m_TargetPID << ", BaseAddress: " + << m_TargetBaseAddress << ", NTHeader: " << m_NTHeader; + throw std::runtime_error(err_str.str()); + return false; + } + + reloc = (IMAGE_BASE_RELOCATION *)GetPtrFromRVA( + (DWORD)(m_NTHeader->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_BASERELOC].VirtualAddress), + m_NTHeader, (PBYTE)m_DLLPtr); + ImageBase = m_NTHeader->OptionalHeader.ImageBase; + delta = MakeDelta(unsigned long, m_TargetBaseAddress, ImageBase); + + while (1) + { + unsigned long *locBase = + (unsigned long *)GetPtrFromRVA((DWORD)(reloc->VirtualAddress), m_NTHeader, + (PBYTE)m_DLLPtr); + unsigned int numRelocs = (reloc->SizeOfBlock - sizeof(IMAGE_BASE_RELOCATION)) / sizeof(WORD); + + if (nBytes >= m_NTHeader->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_BASERELOC].Size) { + break; + } + + unsigned short *locData = MakePtr(unsigned short *, reloc, sizeof(IMAGE_BASE_RELOCATION)); + for (unsigned int i = 0; i < numRelocs; i++) + { + if (((*locData >> 12) & IMAGE_REL_BASED_HIGHLOW)) + *MakePtr(unsigned long *, locBase, (*locData & 0x0FFF)) += delta; + + locData++; + } + + nBytes += reloc->SizeOfBlock; + reloc = (IMAGE_BASE_RELOCATION *)locData; + } + + return true; }
\ No newline at end of file diff --git a/include/DLLHelper.h b/include/DLLHelper.h index f56db0d..764b16f 100644 --- a/include/DLLHelper.h +++ b/include/DLLHelper.h @@ -13,6 +13,7 @@ public: bool VerifyHeader(); bool InitTargetMemory(); bool FixImports(); + bool FixRelocs(); private: HANDLE m_TargetPID = 0; |