Doom9's Forum - View Single Post - BackupHDDVD, a tool to decrypt AACS protected movies

noclip · 3rd January 2007, 00:40

The volume key has to be in the registers to calculate the CMAC value (and decrypt title keys). If you were to set a breakpoint on the routine that accesses the memory location of the CMAC, you would find the Volume key in the registers.

3rd January 2007, 00:40	#258 \| Link
noclip Registered User Join Date: Dec 2006 Posts: 154	The volume key has to be in the registers to calculate the CMAC value (and decrypt title keys). If you were to set a breakpoint on the routine that accesses the memory location of the CMAC, you would find the Volume key in the registers.