Secure rendering of display surfaces
A protected graphics module can send its output to a display engine securely. Secure communications with the display can provide a level of confidentiality of content generated by protected graphics modules against software and hardware attacks.
1. A method comprising:
sending an output from a protected graphics module to a display engine, wherein said module is part of a graphics processor, said module to assert correctness of execution to a remote party, and said module only executable on said graphics processing unit;
displaying the output on a display screen using the display engine; and
enabling the display engine to enter the protected graphics module.
2. The method of claim 1 including linking a display surface to a secure surface binding table.
3. The method of claim 2 including blocking reads from the display surface.
4. The method of claim 3 including encrypting writes to the display surface using a key associated with the current display context.
5. The method of claim 1 including using a protected graphics entry surface to display a surface.
6. The method of claim 1 including using the protected graphics entry surface to provide a way to access the surface.
7. The method of claim 6 including providing a way to access the surface residing in an enclave page cache.
8. The method of claim 7 including providing a way to access the surface in the enclave page cache using the protected graphics entry structure.
9. The method of claim 8 including decrementing an expiry counter in the protected graphics entry structure on a refresh cycle.
10. One or more non-transitory computer readable media storing instructions executed by a processor to perform a sequence comprising:
providing a secure output from a protected graphics module to a display engine, wherein said module is part of a graphics processor, said module to assert correctness of execution to a remote party, and said module only executable on said graphics processing unit;
displaying the output on a display screen using the display engine and;
enabling the display engine to enter the protected graphics module.
11. The media of claim 10 , said sequence including linking a display surface to a secure surface binding table.
12. The media of claim 11 , said sequence including blocking reads from the display surface.
13. The media of claim 12 , said sequence including encrypting writes to the display surface using a key associated with the current display context.
14. The media of claim 10 , said sequence including using a protected graphics entry surface to display a surface.
15. The media of claim 14 , said sequence including enabling a display engine to enter a protected graphics module.
16. The media of claim 15 , said sequence including using the protected graphics entry surface to provide a way to access the surface.
17. The media of claim 16 , said sequence including providing a way to access the surface residing in an enclave page cache.
18. The media of claim 17 , said sequence including providing a way to access the surface in the enclave page cache using the protected graphics entry structure.
19. The media of claim 18 , said sequence including decrementing an expiry counter in the protected graphics entry structure on a refresh cycle.
20. An apparatus comprising:
a storage: and
a processor, coupled to the storage, to provide a secure output of a protected graphics module for display on a display screen, using a display engine, wherein said module is part of a graphics processor, said module to assert correctness of execution to a remote party, and said module only executable on said graphics processing unit, to said display engine to enter the protected graphics module.
21. The apparatus of claim 20 , said processor to link a display surface to a secure surface binding table.
22. The apparatus of claim 21 , said processor to block reads from the display surface.
23. The apparatus of claim 22 , said processor to encrypt writes to the display surface using a key associated with the current display context.
24. The apparatus of claim 20 , said processor to use a protected graphics entry surface to display a surface.
25. The apparatus of claim 24 , said processor to enable a display engine to enter a protected graphics module.
26. The apparatus of claim 25 , said processor to use the protected graphics entry surface to provide a way to access the surface.
27. The apparatus of claim 20 including an operating system.
28. The apparatus of claim 20 including a battery.
29. The apparatus of claim 20 including firmware and a module to update said firmware.