Countering server-based attacks on encrypted content

摘要

Embodiments of the present invention relate to providing encrypted content to authorized content consumers while providing robust traitor tracing. In one embodiment, a key bundle comprising at least one device key is read. A key block is read. A media key precursor is determined from the key block and the at least one device key. A security program is read. At least one encrypted block key is read. The security program is executed to determine a decrypted block key from the media key precursor and the encrypted block key. Encrypted content is read. The decrypted block key is applied to the encrypted content to obtain decrypted content.

主权项

1. A method comprising:
reading a key bundle comprising at least one device key; reading a key block; determining a media key precursor from the key block and the at least one device key; reading a security program; reading at least one encrypted block key; executing the security program to determine a decrypted block key from the media key precursor and the encrypted block key, wherein executing the security program comprises determining a block master key from the media key precursor and providing the block master key to the security program; reading encrypted content; applying the decrypted block key to the encrypted content to obtain decrypted content.