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julian.tuminaro@gmail.com
53e9ecffde
Current implementation of find_os is based on the hard-coded values for different Windows version. It uses the value for get the address to start looking for DOS header in the given specified range. However, this is not scalable to all version of Windows as it will require us to keep adding new entries and also due to KASLR, chances of not hitting the PE header is significant. We implement a way for 64-bit systems to use IDT entry to get a valid exception/interrupt handler and then move back into the memory to find the valid DOS header. Since IDT entries are protected by PatchGuard, we think our assumption that IDT entries will not be corrupted is valid for our purpose. Once we have the image base, we search for the DBGKD_GET_VERSION64 structure type in .data section to get information required for handshake. Currently, this is a work in progress feature and current patch only supports the handshake and memory read/write on 64-bit systems. NOTE: This is the Updated version of the previous patch submitted NOTE: This has currently been only tested when debugging was not enabled on the guest Windows. Signed-off-by: Jenish Rakholiya <rjenish@cmu.edu> Signed-off-by: Julian Tuminaro <jtuminar@andrew.cmu.edu> Reviewed-by: Tim Deegan <tim@xen.org> Reviewed-by: Paul Durrant <paul@xen.org>