Implementing portable content protection to secure secrets

• US 7,584,354 B2
• Filed: 01/31/2003
• Issued: 09/01/2009
• Est. Priority Date: 01/31/2003
• Status: Expired due to Fees

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Graunke, Gary L.
• Primary Examiner(s): Brown; Christopher J
• Application Number:
  US10/355,967
• Publication Number:
  US 20040153661A1
• Time in Patent Office: 2,405 Days
• Field of Search: 713/167, 717/137, 717/147, 717/156, 717/144, 717/140, 726/30
• US Class Current: 713/167
• CPC Class Codes: G06F 21/125 by manipulating the program code, e.g. source code, compiled code, interpreted code, machine code
• CPC Class Codes: G06F 21/14 against software analysis or reverse engineering, e.g. by obfuscation

Abstract

A source-level compiler may randomly select compilation conventions to implement portable content protection, securing the secrets embedded in a program by shuffling associated data. The program may be developed using a source language that is applicative on the associated data. To obscure the embedded secrets, in one embodiment, pre-compiler software may be deployed for compiling the program in a random-execution-order based on a random seed indication that randomly selects compilation conventions and a shuffling algorithm that moves the associated data across the program during execution.

Claims

1. A method executed by a processor based system comprising:

compiling a program in a random-execution-order to conceal a secret;

wherein compiling the program in the random-execution-order includes shuffling data across the program during compiling;

using a source language to identify one or more memory allocation and parallel stream objects of the program; and

enabling said random-execution-order of the program based on said one or more memory allocation and parallel stream objects;

using an applicative source language in a single-assignment semantics dialect to obtain the source code for the program;

introducing reference counting for heap-allocated objects to assist with real-time memory recycling for the single-assignment semantics dialect; and

executing the program in the random-execution-order to preserve upon recompilation the single-assignment semantics dialect of the applicative source language.

2. The method of claim 1 including using a seed indication to randomly select compilation conventions for a different compilation of the program.

3. The method of claim 1 including:

embedding said secret in the source code of the program; and

transforming the source code of the program in a tamper-resistant manner into compiler-modified source code that is platform-independent.

4. The method of claim 3 including protecting said secret from disclosure upon recompilation of the compiler-modified source code into object code on a platform-specific compiler by optimizing code obfuscation.

5. The method of claim 2 including:

determining whether the seed indication is available for use with debug information; and

if so, permitting recompilation of the program based on the seed indication and the debug information.

6. The method of claim 1 including:

building for the program and the associated data a control flow graph indicating one or more data and code pats within the source code of the program;

identifying in the associated data one or more data variables to randomly allocate as array elements; and

inserting code in the source code of the program to shuffle data along at least one data path of said one or more data paths for at least one data variable of said one or more data variables.

7. The method of claim 3, including:

introducing at least one of redundant and auxiliary computations in the compiler-modified source code; and

detecting during recompiling whether a change is made in the at least one of redundant and auxiliary computations.

8. An article comprising a medium storing instructions that,

when executed by a processor-based system result in:

compiling a program in a random-execution-order to conceal a secret;

wherein compiling the program in the random-execution-order includes shuffling data across the program during execution;

using a source language to identify one or more memory allocation and parallel stream objects of the program; and

enabling said random-execution-order of the program based on said one or more memory allocation and parallel stream objects;

using an applicative source language in a single-assignment semantics dialect to obtain the source code for the program;

introducing reference counting for heap-allocated objects to assist with real-time memory recycling for the single-assignment semantics dialect; and

executing the program in the random-execution-order to preserve upon recompilation the single-assignment semantics dialect of the applicative source language.

9. The ankle of claim 8, comprising a medium storing instructions that, when executed by a processor-based system result in using a seed indication to randomly select compilation conventions for a different compilation of the program.

10. The article of claim 8, comprising a medium storing instructions that, when executed by a processor-based system result in:

embedding said secret in the source code of the program; and

transforming the source code of the program in a tamper-resistant manner into compiler-modified source code that is platform-independent.

11. The article of claim 10, comprising a medium storing instructions that, when executed by a processor-based system result in protecting said secret from disclosure upon recompilation of the compiler-modified source code into object code on a platform-specific compiler by optimizing code obfuscation.

12. The article of claim 9, comprising a medium storing instructions that, when executed by a processor-based system result in:

determining whether the seed indication is available for use with debug information; and

if so, permitting recompilation of the program based on the seed indication and the debug information.

13. The article of claim 8, comprising a medium storing instructions that, when executed by a processor-based system result in:

building for the program and the associated data a control flow graph indicating one or more data and code paths within the source code of the program;

identifying in the associated data one or more data variables to randomly allocate as array elements;

inserting code in the source code of the program to shuffle data along at least one data path of said one or more data paths for at least one data variable of said one or more data variables.

14. The article of claim 10, comprising a medium storing instructions that, when executed by a processor-based system result in:

introducing at least one of redundant and auxiliary computations in the compiler-modified source code; and

detecting during recompiling whether a change is made in the at least one of redundant and auxiliary computations.