Extending the number of applications for accessing protected content in a media using media key blocks
View Patent ↗Embodiments of the invention relate to digital content protection for recordable media using encryption and decryption based on device keys in the media. The invention increases the number of extended applications supported the media key blocks and facilitates the assignment of the applications to the media key blocks. One aspect of the invention concerns a method that comprises assigning a first media key block in a protected area of the media for extended applications accessing protected content, processing the first media key block with a first device key set to generate a first media key, and for each extended application, creating a second media key block in a protected area of the media. The second media key block is processed to generate a second media key. A content-accessing device processes the first and second media keys in order to access protected content.
1. A method, comprising:
retrieving a first media key block on a protected area of a media, the first media key block being previously designated by a media association for new applications accessing protected content stored on the media;
processing the first media key block with a first device key set to generate a first media key;
for a particular application among the new applications, processing a second media key block on the user area the media with a second device key set to generate a second media key, the second media key block being previously designated by a licensing entity for the particular application; and
wherein a content-accessing device, coupled to a processor, uses the first media key and second media key to access the protected content and implements the particular application.
2. The method of claim 1 , wherein the first and second keys are processed sequentially.
3. The method of claim 1 , wherein the first and second keys are processed concurrently.
4. The method of claim 1 , wherein the first and second media keys are combined and processed as a single key.
5. The method of claim 1 , wherein the media is selected from a group consisting: a Secure Digital (SD) card, flash media, and DVD.
6. The method of claim 1 , wherein the content is protected using a standard selected from the group consisting of: Content Protection for Recordable Media (CPRM) standard and Content Protection for Extended Media (CPXM) standard.
7. The method of claim 1 , wherein the first media key block is an updateable media key block.
8. The method of claim 1 , wherein the first media key block is a read-only media key block.
9. The method of claim 1 , wherein the media association is the SD Association.
10. The method of claim 1 , wherein the licensing entity is the 4C Entity.
11. A system, comprising:
a device for accessing protected content in a media;
a memory having computer readable instructions; and
a processor for executing the computer readable instructions, the instructions include:
retrieving a first media key block on a protected area of a media, the first media key block being previously designated by a media association for new applications accessing protected content stored on the media;
processing the first media key block with a first device key set to generate a first media key;
for a particular application among the new applications, processing a second media key block on the user area the media with a second device key set to generate a second media key, the second media key block being previously designated by a licensing entity for the particular application; and
wherein using the first media key and second media key to access the protected content and implement the particular application.
12. The system of claim 11 , wherein the media is selected from a group consisting: a Secure Digital (SD) card, flash media, and DVD.
13. The system of claim 11 , wherein the content is protected using a standard selected from the group consisting of: Content Protection for Recordable Media (CPRM) standard and Content Protection for Extended Media (CPXM) standard.
14. The system of claim 11 , wherein the media association is the SD Association.
15. The system of claim 11 , wherein the licensing entity is the 4C Entity.
16. A computer program product comprising a non-transitory computer readable storage medium having computer readable program code embodied therewith, the computer readable program code being executable by a processor to:
retrieve a first media key block on a protected area of a media, the first media key block being previously designated by a media association for new applications accessing protected content stored on the media;
process the first media key block with a first device key set to generate a first media key;
for a particular application among the new applications, process a second media key block on the user area the media with a second device key set to generate a second media key, the second media key block being previously designated by a licensing entity for the particular application; and
use the first media key and second media key to access the protected content and implement the particular application.
17. The computer program product of claim 16 , wherein the content is protected using on a standard selected from the group consisting of: Content Protection for Recordable Media (CPRM) standard and Content Protection for Extended Media (CPXM) standard.
18. The computer program product of claim 16 , wherein the media is selected from a group consisting: a SD card, flash media, and DVD.
19. The computer program product of claim 16 , wherein the media association is the SD Association.
20. The computer program product of claim 16 , wherein the licensing entity is the 4C Entity.