Wow64

Wow64 (Win32 emulation on 64-bit Windows) refers to the software that permit the execution of 32-bit x86 applications on 64-bit Windows. It is implemented as a set of user-mode Dlls:

  • Wow64.dll: Manages process and thread creation, hooks exception dispatching and base system calls exported by Ntoskrnl.exe. It also implements file system redirection and registry redirection and reflection.

  • Wow64Cpu.dll: Manages the 32-bit CPU context of each running thread inside Wow64, and provides processor architecture-specific support for switching CPU mode from 32bit to 64-bit and vice versa.

  • Wow64Win.dll: Intercepts the GUI system calls exported by Win32k.sys.

The relationship of these Dlls is shown in Figure 3-31.

Figure 3-31. Wow64 architecture

Wow64 Process ...

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