System and method for transmitting and utilizing attachments

• US 8,615,661 B2
• Filed: 03/20/2003
• Issued: 12/24/2013
• Est. Priority Date: 03/20/2002
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Blackberry Limited
• Inventors: Little, Herbert A., Hecht-Enns, Albert, Tapuska, David F., Brown, Michael S., Kirkup, Michael G.
• Primary Examiner(s): Yalew, Fikremariam A
• Application Number:
  US10/508,644
• Publication Number:
  US 20050114671A1
• Time in Patent Office: 3,932 Days
• Field of Search: 713/192, 713/153, 709/206
• US Class Current: 713/182
• CPC Class Codes: H04L 51/063 Content adaptation, e.g. replacement of unsuitable content
• CPC Class Codes: H04L 51/58 Message adaptation for wireless communication
• CPC Class Codes: H04L 63/0428 wherein the data content is protected, e.g. by encrypting or encapsulating the payload
• CPC Class Codes: H04L 63/0464 using hop-by-hop encryption, i.e. wherein an intermediate entity decrypts the information and re-encrypts it before forwarding it
• CPC Class Codes: H04L 63/08 for authentication of entities cryptographic mechanisms or cryptographic arrangements for entity authentication H04L9/32
• CPC Class Codes: H04L 63/0823 using certificates cryptographic mechanisms or cryptographic arrangements for entity authentication involving certificates H04L9/3263
• CPC Class Codes: H04L 63/12 Applying verification of the received information cryptographic mechanisms or cryptographic arrangements for data integrity or data verification H04L9/32
• CPC Class Codes: H04L 63/123 received data contents, e.g. message integrity

Abstract

A method of handling cryptographic information in a communication comprising body elements and attachment elements to a mobile device includes the steps of determining if the communication includes an attachment element comprising cryptographic information and converting the attachment element into a body element upon determining that the communication includes an attachment element comprising cryptographic information.

Claims

1. A system for preventing information contained in a cryptographic attachment from being stripped from a message to a mobile device, the system comprising:

a memory subsystem configured to store data;

a processor being coupled to the memory subsystem and configured to read data from the memory subsystem; and

an inline generator software module stored in the memory subsystem and executable on the processor, the inline generator software module configured to;

identify a cryptographic attachment element in a message having body elements and attachment elements, the cryptographic attachment element including cryptographic information specifying cryptographic protocols associated with the cryptographic attachment element;

extract the cryptographic information from the cryptographic attachment element;

generate a body element by converting the cryptographic attachment element in accordance with the extracted cryptographic information; and

insert the body element into a body part of the message.

2. The system of claim 1 wherein the inline generator software module comprises instructions to generate the body element from the cryptographic information in the cryptographic attachment element and insert the body element into the body part of the message.

3. The system of claim 2, further comprising an extractor table stored in the memory subsystem, the extractor table comprising one or more extraction conditions, each of the extraction conditions defining an extraction criteria for the body element.

4. The system of claim 3, wherein the inline generator software module is further configured to generate conversion data detailing the generation of the body element from the cryptographic information in the cryptographic attachment element.

17. The system of claim 1, wherein the cryptographic attachment element is reconstructed by a receiver based on the body element.

5. A method of preventing information contained in a cryptographic attachment from being stripped from a communication to a mobile device, the communication comprising body elements and attachment elements, the method comprising the steps of:

executing instructions on a processor to determine if the communication includes a cryptographic attachment element, the cryptographic attachment element including cryptographic information specifying cryptographic protocols associated with the cryptographic attachment element; and

executing instructions on the processor to convert the cryptographic attachment element into a body element in accordance with cryptographic information extracted from the cryptographic attachment element.

6. The method of claim 5, wherein the step of converting the cryptographic attachment element into a body element comprises the steps of:

executing instructions on the processor to create the body element; and

executing instructions on the processor to copy the cryptographic information extracted from the attachment element into the body element.

7. The method of claim 6, further comprising the step of executing instructions on the processor to delete the cryptographic attachment element from the communication.

8. The method of claim 7, further comprising the step of executing instructions on the processor to append conversion information to the communication, the conversion information detailing the conversion of the cryptographic attachment element into the body element.

9. The method of claim 8, wherein the step of executing instructions on the processor to append conversion information to the communication comprises the step of including the conversion information in a conversion body element.

10. The method of claim 5, wherein the communication is a Secure Multipurpose Internet Mail Extensions (S/MIME) message, and wherein the step of executing instructions on the processor to determine if the communication includes a cryptographic attachment element comprises the steps of:

identifying an S/MIME entity in the S/MIME message;

determining if the S/MIME entity comprises cryptographic information; and

upon determining that the S/MIME entity comprises cryptographic information, determining if the S/MIME entity has an attachment content disposition.

11. The method of claim 10, wherein the step of executing instructions on the processor to convert the attachment element into a body element upon determining that the communication includes an attachment element comprising cryptographic information comprises the step of:

upon determining that the S/MIME entity has an attachment content disposition, changing the attachment content disposition to an inline content disposition.

12. The method of claim 11, further comprising the step of executing instructions on the processor to append conversion information to the S/MIME message, the conversion information detailing the conversion of the attachment content disposition to an inline content disposition.

13. The method of claim 5, wherein the step of executing instructions on the processor to convert the cryptographic attachment element into a body element comprises the step of executing instructions on the processor to recast the cryptographic information.

14. The method of claim 13, wherein the step of executing instructions on the processor to recast the cryptographic information comprises the steps of:

selecting a subset of the cryptographic information; and

including only the subset of the cryptographic information in the body element.

15. The method of claim 14, wherein the cryptographic information comprises a digital certificate, and wherein the subset of the cryptographic information comprises a public key.

16. The system of claim 5, wherein the attachment element is not converted into a body element if the attachment element does not comprise cryptographic information.