From 07fd9cc99998a21bf1ccec74db8e1b56067223f7 Mon Sep 17 00:00:00 2001 From: _xeroxz Date: Sat, 14 Aug 2021 18:18:29 -0700 Subject: [PATCH] updated vmp2 file format structures and how i serialize them... --- dependencies/vmprofiler | 2 +- src/main.cpp | 142 +++++++++++++++++++++++++++++++++------- 2 files changed, 120 insertions(+), 24 deletions(-) diff --git a/dependencies/vmprofiler b/dependencies/vmprofiler index fb59f8f..b336e01 160000 --- a/dependencies/vmprofiler +++ b/dependencies/vmprofiler @@ -1 +1 @@ -Subproject commit fb59f8f58f86a7abe461999315bfbd40bca9622c +Subproject commit b336e0145d3655ebd7b43abd7338016f36640ab0 diff --git a/src/main.cpp b/src/main.cpp index 0252fb1..e5de3c7 100644 --- a/src/main.cpp +++ b/src/main.cpp @@ -13,6 +13,10 @@ int __cdecl main( int argc, const char *argv[] ) parser.add_argument().name( "--bin" ).description( "path to unpacked virtualized binary..." ); parser.add_argument().name( "--out" ).description( "output file name..." ); parser.add_argument().name( "--unpack" ).description( "unpack a vmp2 binary..." ); + parser.add_argument() + .name( "--emuall" ) + .description( "scan for all vm enters and trace all of them... this may take a few minutes..." ); + parser.add_argument() .name( "--locateconst" ) .description( "scan all vm enters for a specific constant value...\n" ); @@ -137,7 +141,8 @@ int __cdecl main( int argc, const char *argv[] ) for ( const auto &code_block : code_blocks ) { - const auto _code_block_size = sizeof vmp2::v4::code_block_t + ( code_block.jcc.block_addr.size() * 8 ); + const auto _code_block_size = sizeof vmp2::v4::code_block_t + ( code_block.jcc.block_addr.size() * 8 ) + + code_block.vinstrs.size() * sizeof vm::instrs::virt_instr_t; vmp2::v4::code_block_t *_code_block = reinterpret_cast< vmp2::v4::code_block_t * >( malloc( _code_block_size ) ); @@ -145,25 +150,23 @@ int __cdecl main( int argc, const char *argv[] ) // serialize block meta data... _code_block->vip_begin = code_block.vip_begin; _code_block->next_block_offset = _code_block_size; - _code_block->jcc.num_block_addrs = code_block.jcc.block_addr.size(); + _code_block->vinstr_count = code_block.vinstrs.size(); + _code_block->has_jcc = code_block.jcc.has_jcc; + _code_block->jcc_type = code_block.jcc.type; + _code_block->num_block_addrs = code_block.jcc.block_addr.size(); - // serialize jcc data... + // serialize jcc branches... for ( auto idx = 0u; idx < code_block.jcc.block_addr.size(); ++idx ) - _code_block->jcc.block_addr[ idx ] = code_block.jcc.block_addr[ idx ]; - - output.write( reinterpret_cast< const char * >( _code_block ), - sizeof vmp2::v4::code_block_t + ( code_block.jcc.block_addr.size() * 8 ) ); + _code_block->branch_addr[ idx ] = code_block.jcc.block_addr[ idx ]; - // serialize virtual instructions... - auto vinstr_count = ( std::uint32_t )code_block.vinstrs.size(); - output.write( reinterpret_cast< const char * >( &vinstr_count ), sizeof vinstr_count ); + auto block_vinstrs = reinterpret_cast< vm::instrs::virt_instr_t * >( + reinterpret_cast< std::uintptr_t >( _code_block ) + sizeof vmp2::v4::code_block_t + + ( code_block.jcc.block_addr.size() * 8 ) ); for ( auto idx = 0u; idx < code_block.vinstrs.size(); ++idx ) - { - const auto& vinstr = code_block.vinstrs[ idx ]; - output.write( reinterpret_cast< const char * >( &vinstr ), sizeof vinstr ); - } + block_vinstrs[ idx ] = code_block.vinstrs[ idx ]; + output.write( reinterpret_cast< const char * >( _code_block ), _code_block_size ); free( _code_block ); } output.close(); @@ -196,28 +199,121 @@ int __cdecl main( int argc, const char *argv[] ) output.write( reinterpret_cast< char * >( unpacked_bin.data() ), unpacked_bin.size() ); output.close(); } - else if ( parser.exists( "bin" ) && parser.exists( "locateconst" ) ) + else if ( parser.exists( "bin" ) && parser.exists( "emuall" ) && parser.exists( "out" ) ) { const auto module_base = reinterpret_cast< std::uintptr_t >( LoadLibraryExA( parser.get< std::string >( "bin" ).c_str(), NULL, DONT_RESOLVE_DLL_REFERENCES ) ); - const auto const_val = std::strtoull( parser.get< std::string >( "locateconst" ).c_str(), nullptr, 16 ); const auto image_base = umtils->image_base( parser.get< std::string >( "bin" ).c_str() ); const auto image_size = NT_HEADER( module_base )->OptionalHeader.SizeOfImage; auto vm_handler_tables = vm::locate::all_handler_tables( module_base ); auto vm_enters = vm::locate::all_vm_enters( module_base, vm_handler_tables ); - std::printf( "> number of vm enters = %d\n", vm_enters.size() ); - if ( std::find_if( vm_enters.begin() + 1, vm_enters.end(), - [ & ]( const std::pair< std::uint32_t, std::uint32_t > &vm_enter_data ) -> bool { - return vm_enter_data.second == vm_enters[ 0 ].second; - } ) != vm_enters.end() ) + std::vector< std::vector< vm::instrs::code_block_t > > virt_rtns; + for ( const auto &[ vm_enter_offset, encrypted_rva ] : vm_enters ) { - std::printf( "> optimizations can be done.\n" ); - std::getchar(); + std::printf( "> emulating vm enter at rva = 0x%x\n", vm_enter_offset ); + vm::ctx_t vm_ctx( module_base, image_base, image_size, vm_enter_offset ); + + if ( !vm_ctx.init() ) + { + std::printf( "[!] failed to init vmctx... this can be for many reasons..." + " try validating your vm entry rva... make sure the binary is unpacked and is" + "protected with VMProtect 2...\n" ); + return -1; + } + + vm::emu_t emu( &vm_ctx ); + + if ( !emu.init() ) + { + std::printf( "[!] failed to init emulator...\n" ); + return -1; + } + + std::vector< vm::instrs::code_block_t > code_blocks; + + if ( !emu.get_trace( code_blocks ) ) + { + std::printf( "[!] something failed during tracing, review the console for more information...\n" ); + continue; + } + + std::printf( "> number of blocks = %d\n", code_blocks.size() ); + virt_rtns.push_back( code_blocks ); } + std::printf( "> traced %d virtual routines...\n", virt_rtns.size() ); + std::printf( "> serializing results....\n" ); + + vmp2::v4::file_header file_header; + file_header.magic = VMP_MAGIC; + file_header.epoch_time = std::time( nullptr ); + file_header.version = vmp2::version_t::v4; + file_header.module_base = module_base; + file_header.image_base = image_base; + file_header.vm_entry_rva = 0ull; + file_header.module_offset = sizeof file_header; + file_header.module_size = image_size; + file_header.rtn_count = virt_rtns.size(); + file_header.rtn_offset = image_size + sizeof file_header; + + std::ofstream output( parser.get< std::string >( "out" ), std::ios::binary ); + output.write( reinterpret_cast< const char * >( &file_header ), sizeof file_header ); + output.write( reinterpret_cast< const char * >( module_base ), image_size ); + + for ( auto virt_rtn : virt_rtns ) + { + vmp2::v4::rtn_t rtn{ virt_rtn.size() }; + output.write( reinterpret_cast< const char * >( &rtn ), sizeof vmp2::v4::rtn_t::code_block_count ); + + for ( const auto &code_block : virt_rtn ) + { + const auto _code_block_size = sizeof vmp2::v4::code_block_t + ( code_block.jcc.block_addr.size() * 8 ) + + code_block.vinstrs.size() * sizeof vm::instrs::virt_instr_t; + + vmp2::v4::code_block_t *_code_block = + reinterpret_cast< vmp2::v4::code_block_t * >( malloc( _code_block_size ) ); + + // serialize block meta data... + _code_block->vip_begin = code_block.vip_begin; + _code_block->next_block_offset = _code_block_size; + _code_block->vinstr_count = code_block.vinstrs.size(); + _code_block->has_jcc = code_block.jcc.has_jcc; + _code_block->jcc_type = code_block.jcc.type; + _code_block->num_block_addrs = code_block.jcc.block_addr.size(); + + // serialize jcc branches... + for ( auto idx = 0u; idx < code_block.jcc.block_addr.size(); ++idx ) + _code_block->branch_addr[ idx ] = code_block.jcc.block_addr[ idx ]; + + auto block_vinstrs = reinterpret_cast< vm::instrs::virt_instr_t * >( + reinterpret_cast< std::uintptr_t >( _code_block ) + sizeof vmp2::v4::code_block_t + + ( code_block.jcc.block_addr.size() * 8 ) ); + + for ( auto idx = 0u; idx < code_block.vinstrs.size(); ++idx ) + block_vinstrs[ idx ] = code_block.vinstrs[ idx ]; + + output.write( reinterpret_cast< const char * >( _code_block ), _code_block_size ); + free( _code_block ); + } + } + output.close(); + } + else if ( parser.exists( "bin" ) && parser.exists( "locateconst" ) ) + { + const auto module_base = reinterpret_cast< std::uintptr_t >( + LoadLibraryExA( parser.get< std::string >( "bin" ).c_str(), NULL, DONT_RESOLVE_DLL_REFERENCES ) ); + + const auto const_val = std::strtoull( parser.get< std::string >( "locateconst" ).c_str(), nullptr, 16 ); + const auto image_base = umtils->image_base( parser.get< std::string >( "bin" ).c_str() ); + const auto image_size = NT_HEADER( module_base )->OptionalHeader.SizeOfImage; + + auto vm_handler_tables = vm::locate::all_handler_tables( module_base ); + auto vm_enters = vm::locate::all_vm_enters( module_base, vm_handler_tables ); + + std::printf( "> number of vm enters = %d\n", vm_enters.size() ); for ( const auto &[ vm_enter_offset, encrypted_rva ] : vm_enters ) { std::printf( "> emulating vm enter at rva = 0x%x\n", vm_enter_offset );