It is common practice to embed a version resource (VS_VERSIONINFO) into PE images such as DLL and EXE files. While this resource mainly serves informational purposes, the version information is occasionaly used to perform certain checks, such as verifying the module’s suitability for a particular purpose. Under certain circumstances, however, this versioning information may be too imprecise: Versions are not necessarily incremented after each build, so it is possible that two copies of a module carry the same versioning information, yet differ significantly in their implementation.
When working with symbols, the default case is that you either analyze the current process, a concurrently running process or maybe even the kernel. dbghelp provides special support for these use cases and getting the right symbols to load is usually easy – having access to the process being analyzed, dbghelp can obtain the necessary module information by itself and will come up with the matching symbols. Things are not quite as easy when analyzing symbols for a process (or kernel) that is not running any more or executes on a different machine.
One of the newer additions to the DDK is the aux_klib library, which, among others, offers the routine AuxKlibGetImageExportDirectory. As its name suggests, AuxKlibGetImageExportDirectory offers a handy way to obtain a pointer to the export directory of a kernel module. There is, however, one issue that – at least in my opinion – renders AuxKlibGetImageExportDirectory pretty much useless in most scenarios: Dealing with forwaders. The primary motivation to call AuxKlibGetImageExportDirectory is to either enumerate the exports of a module or to find a specific export.