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Cryptographic protection of usage restrictions in electronic devices

Smeets, Ben LU orcid ; Ståhl, Per and Loreskar, Chris (2012) 8225110
Abstract
An electronic device requires valid control keys to change any usage restriction setting. The device is provided control keys, a secret key, and a signed software object including a batch ID and a hash of the secret key. For each control key, the device generates a cryptographic footprint bound to the device and the secret key. A message authentication code (MAC) of each usage restriction setting is generated, the MAC bound to the device and a control key. To change a usage restriction, the device receives a control key, validates it against the stored footprint, changes the usage restriction settings, and generates a new usage restriction setting MAC. The control key footprints are bound to the secret key, but the device retains only a... (More)
An electronic device requires valid control keys to change any usage restriction setting. The device is provided control keys, a secret key, and a signed software object including a batch ID and a hash of the secret key. For each control key, the device generates a cryptographic footprint bound to the device and the secret key. A message authentication code (MAC) of each usage restriction setting is generated, the MAC bound to the device and a control key. To change a usage restriction, the device receives a control key, validates it against the stored footprint, changes the usage restriction settings, and generates a new usage restriction setting MAC. The control key footprints are bound to the secret key, but the device retains only a hash of the secret key. (Less)
Please use this url to cite or link to this publication:
inventor
LU orcid ; Ståhl, Per and Loreskar, Chris
organization
publishing date
type
Patent
publication status
published
subject
patent number
8225110
language
English
LU publication?
yes
id
74fef603-af16-443a-acd0-6fcd34a12563
alternative location
https://worldwide.espacenet.com/patent/search?q=pn%3DUS8225110B2
date added to LUP
2021-10-24 12:37:40
date last changed
2021-10-25 16:20:10
@misc{74fef603-af16-443a-acd0-6fcd34a12563,
  abstract     = {{An electronic device requires valid control keys to change any usage restriction setting. The device is provided control keys, a secret key, and a signed software object including a batch ID and a hash of the secret key. For each control key, the device generates a cryptographic footprint bound to the device and the secret key. A message authentication code (MAC) of each usage restriction setting is generated, the MAC bound to the device and a control key. To change a usage restriction, the device receives a control key, validates it against the stored footprint, changes the usage restriction settings, and generates a new usage restriction setting MAC. The control key footprints are bound to the secret key, but the device retains only a hash of the secret key.}},
  author       = {{Smeets, Ben and Ståhl, Per and Loreskar, Chris}},
  language     = {{eng}},
  month        = {{07}},
  note         = {{Patent, Patent Number: 8225110}},
  title        = {{Cryptographic protection of usage restrictions in electronic devices}},
  url          = {{https://worldwide.espacenet.com/patent/search?q=pn%3DUS8225110B2}},
  year         = {{2012}},
}