Method and apparatus for secure processing of XML-based documents

• US 20060143557A1
• Filed: 12/27/2004
• Published: 06/29/2006
• Est. Priority Date: 12/27/2004
• Status: Active Grant

• Current Assignee: WSOU Investments, LLC (WSOU Holdings, LLC)
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Garofalakis, Minos N., Fan, Wenfei, Chan, Chee-Yong
• Granted Patent: US 7,433,870 B2
• Time in Patent Office: Days
• US Class Current: 715/239
• CPC Class Codes: G06F 16/8373 Query execution
• CPC Class Codes: G06F 21/6245 Protecting personal data, e.g. for financial or medical purposes
• CPC Class Codes: Y10S 707/99939 Privileged access
• CPC Class Codes: Y10S 707/99945 Object-oriented database structure processing

Abstract

Method for providing controlled access to an XML document includes defining at least one access control policy for a user of the XML document, deriving a security view of the XML document for the user based upon said access control policy and schema level processing of the XML document and translating a user query based on the security view of the XML document to an equivalent query based on the XML document. An apparatus for same includes means for defining an access control policy for a user of the XML document and means for deriving a security view of the XML document for the user based on said access control policy and schema level processing of the XML document. Also included are means for translating a user query based on the security view of the XML document to an equivalent query based on the XML document.

Claims

1. A method for securely providing access to XML data of an XML document comprising:

(a) defining at least one access control policy for at least one user of the XML document; and

(b) deriving a security view of the XML document for said at least one user based upon said access control policy and schema level processing of the XML document.

2. The method of claim 1 further comprising:

(c) translating a user query based on the security view of the XML document to an equivalent query based on the XML document.

3. The method of claim 1 wherein the step of deriving a security view further comprises invoking a first sub process that includes:

determining if a first accessible element type of an XML document DTD representing said XML document has been previously processed.

4. The method of claim 3 wherein if the first accessible element type has not been previously processed, then the first sub process performs the steps of:

computing a query annotation for each child element in a production rule of the first accessible element type;

computing a view production rule for first accessible element type in a view DTD representing an accessible portion of the XML document; and

computing a security view for each child element in the production rule of the first accessible element type.

5. The method of claim 4 wherein the step of computing a security view for each child element in the production rule of the first accessible element type further comprises invoking a second sub process if a child element in the production rule of the first accessible element type is inaccessible;

otherwise, the first sub process is invoked for said child element.

6. The method of claim 5 wherein then the second sub process performs the steps of:

computing a path for each child element in a production rule of a first inaccessible element type;

computing an expression for said first inaccessible element type; and

computing a security view for each child element in the production rule of the first inaccessible element type.

7. The method of claim 6 wherein the step of computing a security view for each child element in the production rule of the first inaccessible element type further comprises invoking the second sub process if a child element in the production rule of the first inaccessible element type is inaccessible;

otherwise, the first sub process is invoked for said child element.

8. The method of claim 2 wherein the step of translating the user query based on the security view of the XML document further comprises:

iteratively computing at least one local translation corresponding to at least one subquery of the first accessible element type that is part of the user query.

9. The method of claim 8 wherein iteratively computing at least one local translation further comprises:

computing at least one local translation corresponding to at least one subquery of a child element of the first accessible element type; and

combining all of said at least one local translation(s) corresponding to at least one subquery of a child element.

10. A method for securely providing access to XML data of an XML document comprising:

(a) defining an access control policy for the XML document via a document Data Type Definition (DTD) associated therewith; and

(b) manipulating information pertaining to the DTD of the XML document to create a security view of the XML document.

11. The method of claim 10 further comprising:

(c) translating a query formed from the security view of the XML document to an equivalent query over the XML document.

12. The method of claim 10 wherein the step of manipulating information pertaining to the DTD further comprises invoking a first sub process that includes:

determining if a first accessible element type of an XML document DTD representing said XML document has been previously processed.

13. The method of claim 12 wherein if the first accessible element type has not been previously processed, then the first sub process performs the steps of:

computing a query annotation for each child element in a production rule of the first accessible element type;

computing a view production rule for first accessible element type in a view DTD representing an accessible portion of the XML document; and

computing a security view for each child element in the production rule of the first accessible element type.

14. The method of claim 13 wherein the step of computing a security view for each child element in the production rule of the first accessible element type further comprises invoking a second sub process if a child element in the production rule of the first accessible element type is inaccessible;

otherwise, the first sub process is invoked for said child element.

15. Apparatus for performing an operation of securely providing access to XML data of an XML document comprising:

means for defining at least one access control policy for at least one user of the XML document; and

means for deriving a security view of the XML document for said at least one user based upon said access control policy and schema level processing of the XML document.

16. The apparatus of claim 15 further comprising:

means for translating a user query based on the security view of the XML document to an equivalent query based on the XML document.

17. The apparatus of claim 15 wherein the means for defining said at least one access control policy further comprises an access specification.

18. The apparatus of claim 17 wherein the access specification annotates a document DTD representing the XML document.

19. The apparatus of claim 15 wherein the means for deriving a security view of the XML document for said at least one user further comprises a security view definition that defines query annotations in a document DTD representing the XML document.

20. The apparatus of claim 16 wherein the means for translating a user query based on the security view of the XML document to an equivalent query based on the XML document further comprises a query evaluator that maps one or more nodes in the security view to corresponding one or more nodes in the document DTD representing the XML document.