Read and write optimization for protected area of memory

• US 8,775,827 B2
• Filed: 03/28/2011
• Issued: 07/08/2014
• Est. Priority Date: 03/28/2011
• Status: Expired due to Fees

• Current Assignee: Media IP LLC.
• Original Assignee: Media IP LLC.
• Inventors: Zipperer, Joseph P., Hansen, Kim
• Primary Examiner(s): Zecher, Cordelia
• Assistant Examiner(s): Savenkov, Vadim
• Application Number:
  US13/073,802
• Publication Number:
  US 20120254629A1
• Time in Patent Office: 1,198 Days
• Field of Search: 713/193
• US Class Current: 713/193
• CPC Class Codes: G06F 12/1408 by using cryptography for digital transmission H04L9/00
• CPC Class Codes: G06F 12/1433 for a module or a part of a module
• CPC Class Codes: G06F 21/10 Protecting distributed programs or content, e.g. vending or licensing of copyrighted material protection in video systems or pay television H04N7/16 ; Digital rights management [DRM]
• CPC Class Codes: G06F 21/445 by mutual authentication, e.g. between devices or programs
• CPC Class Codes: G06F 21/53 by executing in a restricted environment, e.g. sandbox or secure virtual machine
• CPC Class Codes: G06F 21/572 Secure firmware programming, e.g. of basic input output system [BIOS]
• CPC Class Codes: G06F 21/77 in smart cards
• CPC Class Codes: G06F 21/79 in semiconductor storage media, e.g. directly-addressable memories
• CPC Class Codes: G06F 2212/2146 being detachable, e.g.. USB memory
• CPC Class Codes: G06F 2221/2149 Restricted operating environment

Abstract

A system (and method) to update content of a secure area of a secure digital (SD) card is disclosed. The system performs a first authenticated key exchange to access the secure area of the secure digital memory. The system reads content from the secure area in response to successful performance of the first authenticated key exchange. The system modifies the content in a memory of a computer system. The system performs a second authenticated key exchange to access the secure area of the secure digital card in preparation to write to the secure area of the secure digital memory. The system then writes modified content to the secure area of the secure digital memory in response to successful performance of the second authenticated key exchange.

Claims

1. A method in an authorized computer application program for optimizing access of content stored in a secure area of a secure digital (SD) memory, without performing a separate authenticated key exchange for each access to the secure area, the method comprising:

performing a first authenticated key exchange to access the secure area of the secure digital memory;

in response to successful performance of the first authenticated key exchange, performing a plurality of read operations of secure content from the secure area of the secure digital memory into a main memory of a computer system for access by the authorized computer application program, without performing additional authenticated key exchange operations for each of the performed plurality of read operations;

also in response to successful performance of the first authenticated key exchange, performing a plurality of read operations of user content from a user area of the secure digital memory;

modifying, while the secure content is in the main memory, the secure content previously read into the main memory of the computer system from the secure area of the secure digital memory;

performing a second authenticated key exchange to access the secure area of the secure digital card in preparation to write to the secure area of the secure digital memory;

in response to successful performance of the second authenticated key exchange, performing a plurality of write operations to write the modified secure content back to the secure area of the secure digital memory without performing additional authenticated key exchange operations for each of the performed plurality of write operations; and

also in response to successful performance of the second authenticated key exchange, performing a plurality of write operations of user content to the user area of the secure digital memory.

2. The method of claim 1, wherein the secure digital memory is in a secure digital card configuration.

3. The method of claim 1, wherein the step of performing a plurality of write operations to write the modified secure content back to the secure area of the secure digital memory is suppressed for read-only processing.

4. A non-transitory computer readable storage medium comprising instructions that, when executed, cause at least one processor to:

perform a first authenticated key exchange to access a secure area of a secure digital memory;

in response to successful performance of the first authenticated key exchange, perform a plurality of read operations to read secure content from the secure area of the secure digital memory into a main memory of a computer system, without performing additional authenticated key exchange operations for each of the performed plurality of read operations;

also in response to successful performance of the first authenticated key exchange, performing a plurality of write operations of user content from a user area of the secure digital memory;

modify, while the secure content is in the main memory, the secure content previously read into the main memory of the computer system from the secure area of the secure digital memory;

perform a second authenticated key exchange to access the secure area of the secure digital card in preparation to write to the secure area of the secure digital memory;

in response to successful performance of the second authenticated key exchange, perform a plurality of write operations write the modified secure content back to the secure area of the secure digital memory, without performing additional authenticated key exchange operations for each of the performed plurality of write operations; and

also in response to successful performance of the second authenticated key exchange, performing a plurality of write operations of user content from a user area of the secure digital memory;

5. The computer readable storage medium of claim 4, wherein the secure digital memory is in a secure digital card configuration.

6. The computer readable storage medium of claim 4, wherein instructions to perform a plurality of write operations to write the modified secure content back to the secure area further comprise instructions to suppress the write operations for read-only processing.

7. A computing system configured to optimize access of content stored in a secure area of a secure digital (SD) memory, without performing a separate authenticated key exchange for each access to the secure area, the system comprising:

a memory; and

a processor, the processor configured to;

perform a first authenticated key exchange to access the secure area of the secure digital memory;

in response to successful performance of the first authenticated key exchange, perform a plurality of read operations to read secure content from the secure area of the secure digital memory into the memory of a computer system, without performing additional authenticated key exchange operations for each of the performed plurality of read operations;

also in response to successful performance of the first authenticated key exchange, performing a plurality of read operations of user content from a user area of the secure digital memory;

modify, while the secure content is in the memory, the secure content previously read into the memory;

perform a second authenticated key exchange to access the secure area of the secure digital card in preparation to write to the secure area of the secure digital memory;

in response to successful performance of the second authenticated key exchange, perform a plurality of write operations to write the modified secure content from the memory back to the secure area of the secure digital memory without performing additional authenticated key exchange operations for each of the performed plurality of write operations; and

also in response to successful performance of the second authenticated key exchange, perform a plurality of write operations of user content to the user area of the secure digital memory.

8. The computing system of claim 7, further comprising a secure digital card input configured to receive a secure digital card and wherein the secure digital memory is a secure digital card.

9. The computing system of claim 7, wherein the processor is further configured to suppress the performing of the write operations to write of the modified secure content from the memory back to the secure area for read-only processing.