Secure garbage collection on a mobile device

• US 10,210,081 B2
• Filed: 12/23/2016
• Issued: 02/19/2019
• Est. Priority Date: 03/20/2002
• Status: Expired due to Term

• Current Assignee: Cloud Software Group Switzerland GmbH
• Original Assignee: Citrix Systems International GmbH (Cloud Software Group)
• Inventors: Little, Herbert Anthony, Adams, Neil Patrick, Janhunen, Stefan E., Dahms, John Fredric Arthur
• Primary Examiner(s): Gergiso, Techane
• Application Number:
  US15/389,756
• Publication Number:
  US 20170168932A1
• Time in Patent Office: 788 Days
• CPC Class Codes: G06F 12/0253 Garbage collection, i.e. reclamation of unreferenced memory
• CPC Class Codes: G06F 12/0261 using reference counting
• CPC Class Codes: G06F 12/1408 by using cryptography for digital transmission H04L9/00
• CPC Class Codes: G06F 16/951 Indexing; Web crawling techniques
• CPC Class Codes: G06F 21/62 Protecting access to data via a platform, e.g. using keys or access control rules
• CPC Class Codes: G06F 2212/1044 Space efficiency improvement
• CPC Class Codes: G06F 2212/1052 Security improvement
• CPC Class Codes: G06F 2212/171 Portable consumer electronics, e.g. mobile phone
• CPC Class Codes: G06F 2212/402 Encrypted data
• CPC Class Codes: G06F 2212/702 Conservative garbage collection
• CPC Class Codes: G06F 2221/2143 Clearing memory, e.g. to prevent the data from being stolen
• CPC Class Codes: H04L 63/0435 wherein the sending and receiving network entities apply symmetric encryption, i.e. same key used for encryption and decryption cryptographic mechanisms or cryptographic arrangements for symmetric key encryption H04L9/06
• CPC Class Codes: H04L 63/061 for key exchange, e.g. in peer-to-peer networks cryptographic mechanisms or cryptographic arrangements for key agreement H04L9/0838
• CPC Class Codes: H04L 9/00 Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols

Abstract

Methods and systems for performing garbage collection involving sensitive information on a mobile device are described herein. Secure information is received at a mobile device over a wireless network. The sensitive information is extracted from the secure information. A software program operating on the mobile device uses an object to access the sensitive information. Secure garbage collection is performed upon the object after the object becomes unreachable.

Claims

1. A method for performing secure garbage collection involving unreferenced data objects on a computing device, the method comprising:

determining that a particular data object has become unreferenced; and

in response to determining that the particular data object has become unreferenced;

calling a wipe function to overwrite the addressable storage memory of the computing device where a first, second, and third data objects are stored, wherein the third data object is the particular data object, and

reclaiming the addressable storage memory where the first, second, and third data objects were stored.

2. The method of claim 1, further comprising:

receiving information over a network;

creating the first data object corresponding to the received information;

storing the first data object in an addressable storage memory on the computing device; and

extracting the second data object from the first data object, wherein the second data object is accessible using the third data object.

3. The method of claim 2, wherein the first data object is a secure data object comprising an encrypted message, the second data object is a sensitive data object comprising an unencrypted message of the first data object, and the third data object is a user interface object, and wherein said extracting further comprises generating, by a private key, the second data object from the first data object.

4. The method of claim 2, wherein the first, second, and third data objects are indexed inside of storage elements in a reference table in the addressable storage memory.

5. The method of claim 2, wherein said unreferencing is performed in response to receiving a trigger event, the trigger event comprising at least a timeout event, a holster event, a cradle event, a screen lock event, a screen unlock event, an application event, a time zone alteration event, or a communication event.

6. The method of claim 2, wherein the first data object is an S/MIME encrypted message.

7. The method of claim 6, wherein the second data object is an unencrypted version of the S/MIME message.

8. One or more non-transitory computer readable media comprising computer readable instructions that, when executed, cause a computing device to perform:

determining that a particular data object has become unreferenced; and

in response to determining that the particular data object has become unreferenced;

calling a wipe function to overwrite the addressable storage memory of the computing device where a first, second, and third data objects are stored, wherein the third data object is the particular data object, and

reclaiming the addressable storage memory where the first, second, and third data objects were stored.

9. The computer readable media of claim 8, wherein the first data object is a secure data object comprising an encrypted message, the second data object is a sensitive data object comprising an unencrypted message of the first data object, and the third data object is a user interface object, and wherein said extracting further comprises generating, by a private key, the second data object from the first data object.

10. The computer readable media of claim 8, wherein the first, second, and third data objects are indexed inside of storage elements in a reference table in the addressable storage memory.

11. The computer readable media of claim 8, wherein said unreferencing is performed in response to receiving a trigger event, the trigger event comprising at least a timeout event, a holster event, a cradle event, a screen lock event, a screen unlock event, an application event, a time zone alteration event, or a communication event.

12. The computer readable media of claim 8, wherein the first data object is an S/MIME encrypted message.

13. The computer readable media of claim 12, wherein the second data object is an unencrypted version of the S/MIME message.

14. The non-transitory computer readable media of claim 8, wherein the mobile device is one of a mobile communication device, a cellular telephone with messaging capabilities, a mobile device with wireless two-way communications, a data messaging device, or an internet appliance.

15. The non-transitory computer readable media of claim 8, wherein the sensitive information is an S/MIME encrypted message.

16. The non-transitory computer readable media of claim 8, wherein the sensitive information arises from use of a Personal Information Management (PIM) application.

17. The non-transitory computer readable media of claim 8, wherein overwriting the unreachable object includes overwriting the memory location where the unreachable object is stored with a sequence of bits comprising all zeros, all ones, or random data.

18. The non-transitory computer readable media of claim 8, wherein the object is a user interface object configured to display the sensitive information.

19. A system comprising:

a processor; and

memory storing computer readable instructions that, when executed, cause the system to perform;

determining that a particular data object has become unreferenced; and

in response to determining that the particular data object has become unreferenced;

calling a wipe function to overwrite the addressable storage memory of the computing device where a first, second, and third data objects are stored, wherein the third data object is the particular data object, and

reclaiming the addressable storage memory where the first, second, and third data objects were stored.