Updating digitally signed active content elements without losing attributes associated with an original signing user

• US 8,341,616 B2
• Filed: 03/28/2007
• Issued: 12/25/2012
• Est. Priority Date: 03/28/2007
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Kadashevich, A. Julie
• Primary Examiner(s): Zhen, Wei
• Assistant Examiner(s): BROPHY, MATTHEW J
• Application Number:
  US11/692,860
• Publication Number:
  US 20080244554A1
• Time in Patent Office: 2,099 Days
• Field of Search: 717/168
• US Class Current: 717/168
• CPC Class Codes: G06F 21/572 Secure firmware programming, e.g. of basic input output system [BIOS]
• CPC Class Codes: G06F 2221/2141 Access rights, e.g. capability lists, access control lists, access tables, access matrices

Abstract

A method and system for updating digitally signed active elements without losing attributes associated with an originally signing user. An updating entity determines the identity of an originally signing user from the original digital signature of an active content unit to be updated. Privileges associated with the original active content unit are determined from the original contents of the active content unit, or based on the identity of the originally signing user. The updating entity updates the active content unit with the new software version, and associates the original privileges for the active content unit with the new version of the active content unit. The updating entity stores the identity of the originally creating user in an On Behalf of: field of the updated active content unit. The updated active content unit is digitally signed by the updating entity. When a subsequent software update is received for the previously updated digitally signed active content unit, the updating entity determines that the On Behalf of: field is non-empty, and can then determine whether the previous signer has privileges allowing it to digitally sign for other users, and whether any privileges associated with (e.g. indicated within) the active content unit are available to the user identified in the On Behalf of: field. The privileges associated with subsequent updated version of the active content unit can advantageously be based on the identity of the user contained in the On Behalf of: field.

Claims

1. A method of updating an original version of a unit of active content, comprising:

receiving, by an updating entity, a new version of program code for replacing at least a portion of said original version of said unit of active content, wherein said original version of said unit of active content contains a digital signature generated using a private encryption key belonging to said originally signing user;

determining, by said updating entity, the identity of said originally signing user from said digital signature contained in said original version of said unit of active content;

storing, by said updating entity, an indication of said identity of said originally signing user in a field within a new version of said unit of active content, wherein said field associates said new version of said unit of active content with at least one privilege associated with said originally signing user;

writing, by said updating entity, said new version of program code into said new version of said unit of active content; and

digitally signing, by said updating entity, said new version of said unit of active content, including generating a digital signature using a private encryption key belonging to said updating entity.

2. The method of claim 1, wherein said updating entity comprises application server software associated with an application program.

3. The method of claim 1, wherein said updating entity comprises an application platform server software for execution of at least one application program.

4. The method of claim 1, further comprising:

wherein said new version of program code is received from a program code distribution source;

wherein said new version of program code is digitally signed with a digital signature generated using a private encryption key belonging to said program code distribution source; and

authenticating said new version of program code, based on said digital signature generated using a private encryption key belonging to said program code distribution source, prior to updating said digitally signed unit of active content.

5. The method of claim 1, further comprising:

determining a set of privileges associated with said original version of said unit of active content; and

storing indication of said set of privileges associated with said original version of said unit of active content prior to said digitally signing said new version of said unit of active content by updating entity.

6. The method of claim 1, wherein said unit of active content comprises a software agent operable to automatically respond to electronic mail messages sent to said originally signing user.

7. The method of claim 1, further comprising:

receiving a second new version of program code for replacing at least a portion of said updated version of said unit of active content;

determining said identity of said originally signing user from said indication of said identity of said originally signing user in said field within said new version of said unit of active content; and

determining a set of privileges to be associated with a second new version of said unit of active content including said second new version of program code based on said identity of said originally signing user.

8. The method of claim 7, further comprising:

determining, responsive to said digital signature in said new version of said unit of active content generated using said private encryption key belonging to said updating entity, an identity of said updating entity; and

prior to generating said second new version of said unit of active content, determining whether said updating entity has sufficient privileges to digitally sign said unit of active content on behalf of said originally signing user.

9. A system including a non-transitory computer readable storage medium, said non-transitory computer readable storage medium having program code stored thereon for updating an original version of a unit of active content, wherein said program code, when executed, is operable to cause a computer system to:

receive, by an updating entity, a new version of program code for replacing at least a portion of said original version of said unit of active content, wherein said original version of said unit of active content contains a digital signature generated using a private encryption key belonging to said originally signing user;

determine, by said updating entity, the identity of said originally signing user from said digital signature contained in said original version of said unit of active content;

store, by said updating entity, an indication of said identity of said originally signing user in a field within a new version of said unit of active content, wherein said field associates said new version of said unit of active content with at least one privilege associated with said originally signing user;

write said new version of program code into said new version of said unit of active content; and

digitally sign, by the updating entity, said new version of said unit of active content, including generation of a digital signature using a private encryption key belonging to said updating entity.

10. The system of claim 9, wherein said updating entity comprises application server software associated with an application program.

11. The system of claim 9, wherein said updating entity comprises an application platform server software for execution of at least one application program.

12. The system of claim 9, further comprising:

wherein said new version of program code is received from a program code distribution source;

wherein said new version of program code is digitally signed with a digital signature generated using a private encryption key belonging to said program code distribution source; and

wherein said program code, when executed, is further operable to cause said computer system to authenticate said new version of program code, based on said digital signature generated using a private encryption key belonging to said program code distribution source, prior to updating said digitally signed unit of active content.

13. The system of claim 9, wherein said program code, when executed, is further operable to cause said computer system to:

determine a set of privileges associated with said original version of said unit of active content; and

store indication of said set of privileges associated with said original version of said unit of active content prior to said digitally signing said new version of said unit of active content by updating entity.

14. The system of claim 9, wherein said unit of active content comprises a software agent operable to automatically respond to electronic mail messages sent to said originally signing user.

15. The system of claim 9, wherein said program code, when executed, is further operable to cause said computer system to:

receive a second new version of program code for replacing at least a portion of said updated version of said unit of active content;

determine said identity of said originally signing user from said indication of said identity of said originally signing user in said field within said new version of said unit of active content; and

determine a set of privileges to be associated with a second new version of said unit of active content including said second new version of program code based on said identity of said originally signing user.

16. The system of claim 15, wherein said program code, when executed, is further operable to cause said computer system to:

determine, responsive to said digital signature in said new version of said unit of active content generated using said private encryption key belonging to said updating entity, an identity of said updating entity; and

prior to generating said second new version of said unit of active content, determine whether said updating entity has sufficient privileges to digitally sign said unit of active content on behalf of said originally signing user.

17. A computer program product including a non-transitory computer readable storage medium, said non-transitory computer readable storage medium having program code stored thereon for updating an original version of a unit of active content, wherein said program code, when executed, is operable to cause a computer system to:

receive, by an updating entity, a new version of program code for replacing at least a portion of said original version of said unit of active content, wherein said original version of said unit of active content contains a digital signature generated using a private encryption key belonging to said originally signing user;

determine, by said updating entity, the identity of said originally signing user from said digital signature contained in said original version of said unit of active content, wherein said field associates said new version of said unit of active content with at least one privilege associated with said originally signing user;

store, by said updating entity, an indication of said identity of said originally signing user in a field within a new version of said unit of active content;

write said new version of program code into said new version of said unit of active content; and

digitally sign, by said updating entity, said new version of said unit of active content, including generation of a digital signature using a private encryption key belonging to said updating entity.