Secure interface control high-level page management

Patent metadata

Field	Value
Publication number	US-2020285758-A1
Application number	US-201916296457-A
Country	US
Kind code	A1
Filing date	Mar 8, 2019
Priority date	Mar 8, 2019
Publication date	Sep 10, 2020
Grant date	—

Abstract

A method is provided. The method is implemented by a secure interface control of a computer that prevents unauthorized accesses to locations in a memory of the computer. The secure interface control determines that a host absolute page is not previously mapped to a virtual page in accordance with securing the host absolute page and a host virtual page is not already mapped to an absolute page in accordance with securing the host absolute page.

First claim

What is claimed is:

1 . A method comprising:
determining, by a secure interface control of a computer that prevents unauthorized accesses to locations in a memory of the computer, that a host absolute page is not previously mapped to a virtual page in accordance with securing the host absolute page; and determining, by the secure interface control, that a host virtual page is not already mapped to an absolute page in accordance with securing the host absolute page.

2 . The method of claim 1 , wherein the secure interface control marks the host absolute page as secure.

3 . The method of claim 2 , wherein the secure interface control registers the host absolute page for use by the secure interface control, securely decrypts the host absolute page, subsequently un-registers the host absolute page for use by the secure interface control, and registers the host absolute page to the secure domain.

4 . The method of claim 3 , wherein the secure interface control registers the host virtual address with the associated host absolute page to create a host-address pair for use by the secure entity, and checks the host virtual addresses match on access by the secure entity.

5 . The method of claim 3 , wherein the secure interface control locks the host absolute page for use by the secure interface control to prevent other calls to the host absolute page.

6 . The method of claim 5 , wherein the secure interface control unlocks the host absolute page to assign a secure guest domain loaded into the memory.

7 . The method of claim 1 , wherein a secure entity accesses a secure page that has been transparently paged-in by an untrusted entity executing on the computer and is non-secure.

8 . The method of claim 7 , wherein the untrusted entity is a hypervisor, and wherein the secure entity is a secure guest.

9 . The method of claim 7 , wherein hardware presents a program interruption to the untrusted entity indicating a need for decryption of a secure guest page.

10 . The method of claim 9 , wherein the untrusted entity issues an import instruction that provides the host absolute page and the host virtual page.

11 . A computer program product comprising a computer readable storage medium having program instructions embodied therewith, the program instructions executable to cause operations comprising:
determining, by a secure interface control of a computer that prevents unauthorized accesses to locations in a memory of the computer, that a host absolute page is not previously mapped to a virtual page in accordance with securing the host absolute page; and determining, by the secure interface control, that a host virtual page is not already mapped to an absolute page in accordance with securing the host absolute page.

12 . The computer program product of claim 11 , wherein the secure interface control marks the host absolute page as secure.

13 . The computer program product of claim 12 , wherein the secure interface control registers the host absolute page for use by the secure interface control, securely decrypts the host absolute page, subsequently un-registers the host absolute page for use by the secure interface control, and registers the host absolute page to the secure domain.

14 . The computer program product of claim 13 , wherein the secure interface control registers the host virtual address with the associated host absolute page to create a host-address pair for use by the secure entity, and checks the host virtual addresses match on access by the secure entity.

15 . The computer program product of claim 13 , wherein the secure interface control locks the host absolute page for use by the secure interface control to prevent other calls to the host absolute page.

16 . The computer program product of claim 15 , wherein the secure interface control unlocks the host absolute page to assign a secure guest domain loaded into the memory.

17 . The computer program product of claim 11 , wherein a secure entity accesses a secure page that has been transparently paged-in by an untrusted entity executing on the computer and is non-secure,

18 . The computer program product of claim 17 , wherein the untrusted entity is a hypervisor, and wherein the secure entity is a secure guest.

19 . The computer program product of claim 17 , wherein hardware presents a program interruption to the untrusted entity indicating a need for decryption of a secure guest page.

20 . The computer program product of claim 19 , wherein the untrusted entity issues an import instruction that provides the host absolute page and the host virtual page.

21 . A system comprising:
a memory; a secure interface control of the system that prevents unauthorized accesses to locations in the memory, wherein the system performs operations comprising:
determining, by a secure interface control of a computer that prevents unauthorized accesses to locations in a memory of the computer, that a host absolute page is not previously mapped to a virtual page in accordance with securing the host absolute page; and
determining, by the secure interface control, that a host virtual page is not already mapped to an absolute page in accordance with securing the host absolute page.

22 . The system of claim 21 , wherein the secure interface control marks the host absolute page as secure.

23 . The system of claim 22 , wherein the secure interface control registers the host absolute page for use by the secure interface control, securely decrypts the host absolute page, subsequently un-registers the host absolute page for use by the secure interface control, and registers the host absolute page to the secure domain.

24 . The system of claim 23 , wherein the secure interface control registers the host virtual address with the associated host absolute page to create a host-address pair for use by the secure entity, and checks the host virtual addresses match on access by the secure entity.

25 . The system of claim 23 , wherein the secure interface control locks the host absolute page for use by the secure interface control to prevent other calls to the host absolute page.

Assignees

• IBM

Inventors

• Schwidefsky Martin
• Carstens Heiko
• Bradbury Jonathan D
• Heller Lisa Cranton

Classifications

• G06F21/602 Primary

  Providing cryptographic facilities or services · CPC title

• G06F12/145 Primary

  the protection being virtual, e.g. for virtual blocks or segments before a translation mechanism · CPC title

• G06F2212/1052

  Security improvement · CPC title

• G06F2009/45587

  Isolation or security of virtual machine instances · CPC title

• G06F2009/45583

  Memory management, e.g. access or allocation · CPC title