Source identification for unauthorized copies of content

摘要

Systems and methods for authentication generate keys from secret credentials shared between authenticating parties and authenticators. Generation of the keys may involve utilizing specialized information in the form of parameters that are used to specialize keys. Keys and/or information derived from keys held by multiple authorities may be used to generate other keys such that signatures requiring such keys and/or information can be verified without access to the keys. Keys may also be derived to form a hierarchy of keys that are distributed such that a key holder's ability to decrypt data depends on the key's position in the hierarchy relative to the position of a key used to encrypt the data. Key hierarchies may also be used to distribute key sets to content processing devices to enable the devices to decrypt content such that sources or potential sources of unauthorized content are identifiable from the decrypted content.

主权项

1. A computer-implemented method, comprising:
under the control of one or more computer systems configured with executable instructions,
obtaining encrypted data comprising multiple copies of a portion of the encrypted data, each copy of the multiple copies being decryptable using a different key and being distinguishable from at least one other copy of the multiple copies;deriving, based at least in part on a key selected from a plurality of accessible keys, a second key, wherein deriving the second key includes determining output of a preimage-resistant function and wherein the second key is based at least in part on the output of the preimage-resistant function;using the derived second key to decrypt the portion; andproviding the decrypted portion.