new "permanent" dll injection option survives reboots
You can now "install" your injection driver and then issue "permanent"
dll injection requests. The driver will store such permanent requests
and re-apply them automatically, every time the OS reboots. As a result
you no longer need a service or application to restart the whole dll
injection, when the user rebooted the OS.
verification of hook dll's code signing signatures
When using madCodeHook 3.x, you had to make all hook dlls known to the
injection driver, or else the driver would refuse to inject the hook dlls.
Furthermore, every time you touched the hook dlls, the injection driver
needed to be updated, too. This whole solution was very safe, but also
quite uncomfortable. Which is now all the more true, when trying to achieve
SecureBoot compatability in Windows 10, where your drivers need to be sent
in to Microsoft to get co-signed. madCodeHook 4.0 now checks the hook dll's code
siging signature. If it's valid, and if it was signed
with the same certificate as the driver file, then the hook dll is automatically
considered "trusted". This should still be a very secure solution, but it's
now also completely comfortable. As long as you sign your hook dlls with the
same certificate you sign your drivers with, you only need to configure and
sign the driver once now.
API hooks can now optionally record the caller's "thread state"
When trying to detect malware attacks, it's very useful for security
applications to know the exact contents of the registers and the exact
parameters on the stack of the caller of the hooked API. When using
madCodeHook 3.x, it was only possible to get that kind of information by
using hand written assembler callback routines. With madCodeHook 4.0
you can now activate this functionality with a simple flag and then
in your hook callback function simply access all the information through
a comfortable structure.
stable cleanup of your hook dll resources
Usually a hook DLL frees its resources in DllMain(DLL_PROCESS_DETACH). However,
this can be dangerous because of the loader lock. For example, you can't wait
for secondary threads to finish because they're usually blocked from running
while you're in DllMain. madCodeHook itself unhooks all of your API hooks automatically, in the moment
when you uninject your hook DLL - and it's doing that outside of DllMain. In
order to allow you to also cleanup your stuff outside of DllMain, you can call
"RegisterUninjectCallback()". Your callback function will then be called after
madCodeHook has uninstalled your API hooks, and right before FreeLibrary is
called on your hook DLL.
rewritten dll injection technique (for newly created processes)
Although the madCodeHook 3.x injection technique (for newly created processes)
has proven to be very stable and reliable, the whole code was rewritten,
using a simpler and cleaner approach. You'll probably notice no difference,
but in rare situations, the old solution could sometimes produce some
problems, which should be fully gone with the new solution.
improved compatability with other hooking libraries
madCodeHook 3.x used a 6-byte absolute JMP instruction to hook APIs,
while most other hooking libraries are using a 5-byte relative JMP.
Although both approaches are perfectly legit, and madCodeHook's solution
was very stable on its own, sometimes there were compatability problems.
That's especially true if "the other" hooking library was of inferior
quality and didn't know how to properly handle madCodeHook's 6-byte JMP. In order
to improve compatability, I've now also switched to using a 5-byte JMP in madCodeHook 4.0.