Daily Archives: 2010/02/22

The Shim Database

The Shim database is a mystic area inside windows… For example it will display an UAC (admin) prompt if your application-name contains the word “*instal*”.
You can display all available shims with the Application Compatibility Administrator by using the /x command line switch.
Also there is a tool from Heath Steward which dumps the database into an XML file.
Of course, he failed to prvide the source-code of his sample project.
Also, Alex Ionescu wrote a small dump tool, but also has never published it…

So I decided to dig into this almost not documented world and write a small Shim-Dumper and Exe-matching tool (whitch source code 😉 ).

Shim Database Tool (sdb) v1.0
Copyright (C) 2010 Jochen Kalmbach

Usage:  sdb.exe [-noids] [-match] [PathToShimDatabse] [PathToFileName]
 -noids  Will prevent the output of the TagIds
 -match  Will match the provided file with the installed databases
         and displays the activated shims
         In this case 'PathToFileName' is required

NOTE: If no shim database path is provided,
      the default database will be used.

You can use it either for dumping the shimdatabase like:

sdb.exe >ShimDatabase.xml

This will redirect the output to an xml-file and will look something like:

  
   setup32.exe
   WordPerfect Office 2000
   Corel
   
   
   
   
    *
    Corel Corporation
    Corel Setup Wizard
   
   
    programs\wpwin9.exe
    Corel Corporation Limited
    WordPerfect® 9
   
   
    appman\tools\cset90.exe
   
   
    WinXPSP1VersionLie
    0x284e0
    
     
     $
    
    
     *

(be aware: the current Win7 database is about 17 MB!)

You also can use this tool to find out, if an application has a shim applied:

C:>sdb -match MyInstaller.exe
Shim found for file: MyInstaller.exe
Flags: 0x0:
Exe-Shim: 0x35472, Flags: 0x0:
Layer-Flags: 0x0:
Shim-Database: 11111111-1111-1111-1111111111111111

Currently it just displays the TagId of the Shim. You can use this to search the xml-file for the corresponding id.

Have fun, using this tool 😉

The project (VS2008) can be found here:
http://blog.kalmbachnet.de/files/sdb_v1.zip
It will compile for x86 and x64.