CODE SIGNING SYSTEM AND METHOD

• US 20120179917A1
• Filed: 03/06/2012
• Published: 07/12/2012
• Est. Priority Date: 09/21/2000
• Status: Active Grant

• Current Assignee: Blackberry Limited
• Original Assignee: Blackberry Limited
• Inventors: YACH, David P., BROWN, Michael S., LITTLE, Herbert A.
• Granted Patent: US 9,633,178 B2
• Time in Patent Office: Days
• US Class Current: 713/189
• 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 21/121 Restricting unauthorised execution of programs
• CPC Class Codes: G06F 21/51 at application loading time, e.g. accepting, rejecting, starting or inhibiting executable software based on integrity or source reliability
• CPC Class Codes: G06F 21/629 to features or functions of an application
• CPC Class Codes: H04L 63/067 using one-time keys cryptographic mechanisms or cryptographic arrangements for generation of one-time passwords H04L9/0863
• CPC Class Codes: H04L 63/0823 using certificates cryptographic mechanisms or cryptographic arrangements for entity authentication involving certificates H04L9/3263
• CPC Class Codes: H04L 63/123 received data contents, e.g. message integrity
• CPC Class Codes: H04L 63/126 the source of the received data
• CPC Class Codes: H04L 63/1483 service impersonation, e.g. phishing, pharming or web spoofing detection of rogue wireless access points H04W12/12
• CPC Class Codes: H04L 9/321 involving a third party or a trusted authority
• CPC Class Codes: H04L 9/3236 using cryptographic hash functions
• CPC Class Codes: H04L 9/3247 involving digital signatures
• CPC Class Codes: H04W 4/60 Subscription-based services using application servers or record carriers, e.g. SIM application toolkits

Abstract

A code signing system and method is provided. The code signing system operates in conjunction with a signed software application having a digital signature and includes an application platform, an application programming interface (API), and a virtual machine. The API is configured to link the software application with the application platform. The virtual machine verifies the authenticity of the digital signature in order to control access to the API by the software application.

Claims

1. A method of controlling access to a plurality of sensitive application programming interfaces (APIs) on a device by an application signed with a private key, the method comprising:

verifying, by a processor of the device, a digital signature of the application using a public key;

after verifying the digital signature of the application using the public key, allowing the application to access a first sensitive API, the first sensitive API being associated with the public key; and

restricting the application from accessing a second sensitive API, the second sensitive API not being associated with the public key.

2. The method of claim 1, wherein the second sensitive API is associated with a second public key different from the public key associated with the first sensitive API.

3. The method of claim 1 wherein the device comprises a mobile device.

4. The method of claim 1 wherein the public key is associated with an entity that classified the first sensitive API as sensitive.

5. The method of claim 1 wherein the public key is associated with an author of the first sensitive API.

6. The method of claim 1 wherein the public key is associated with a manufacturer of the device.

7. The method of claim 1 wherein the first sensitive API is classified as sensitive by a manufacturer of the device.

8. The method of claim 1 wherein the first sensitive API is classified as sensitive by an author of the first sensitive API.

9. The method of claim 1 wherein the first sensitive API includes a user interface API.

10. The method of claim 1 wherein the first sensitive API interfaces with an input/output (I/O) controller.

11. The method of claim 1 wherein the first sensitive API includes a radio API.

12. The method of claim 1 wherein the first sensitive API interfaces with one or more wireless communication functions.

13. The method of claim 1 wherein the first sensitive API interfaces with address book data.

14. The method of claim 1 wherein the first sensitive API interfaces with calendar data.

15. The method of claim 1 wherein the public key is stored on the device.

16. The method of claim 1 wherein the public key is obtained from a public key repository.

17. The method of claim 1 wherein the first sensitive API is included in an API library.

18. The method of claim 1 wherein the verifying includes:

generating a hash of the application;

applying the public key to the digital signature to obtain an output; and

determining that the hash and the output are equivalent.

19. The method of claim 1 wherein the verifying includes:

generating an abridged version of the application;

applying the public key to the digital signature to obtain an output; and

determining that the abridged version and the output are equivalent.

20. The method of claim 1 wherein the verifying includes:

generating a transformed version of the application;

applying the public key to the digital signature to obtain an output; and

determining that the transformed version and the output are equivalent.

21. The method of claim 1 further comprising:

receiving user input regarding whether to grant the application access to at least one of the sensitive APIs.

22. The method of claim 1 further comprising:

verifying a second digital signature of a second application using a second public key; and

after verifying the second digital signature of the second application using the public key, allowing the second application to access the second sensitive API, the second sensitive API being associated with the second public key.

23. The method of claim 1 further comprising:

failing to verify a second digital signature of a second application using the public key; and

purging the second application.

24. The method of claim 1 wherein the device further includes a non-sensitive API, the method further comprising:

allowing the application to access the non-sensitive API.

25. The method of claim 1 wherein the device further includes a non-sensitive API, the method further comprising:

allowing an unsigned application to access the non-sensitive API.

26. The method of claim 1 further comprising:

restricting an unsigned application from accessing the first sensitive API and the second sensitive API.

27. The method of claim 26 further comprising:

executing the unsigned application on the device.

28. The method of claim 1 further comprising:

determining that a second application is unsigned; and

purging the second application from the device.

29. The method of claim 1 further comprising:

on a second device, verifying a second digital signature of a duplicate of the application using a duplicate of the public key; and

allowing the duplicate application to access a duplicate of the first sensitive API on the second device, the duplicate of the first sensitive API being associated with the duplicate of the public key.

30. A device capable of controlling access to a plurality of sensitive application programming interfaces (APIs) on the device by an application signed with a private key, the device comprising:

a processor capable of executing machine readable instructions for;

verifying a digital signature of the application using a public key;

after verifying the digital signature of the application using the public key, allowing the application to access a first sensitive API, the first sensitive API being associated with the public key; and

restricting the application from accessing a second sensitive API, the second sensitive API not being associated with the public key.