2
$\begingroup$

I am working on Ciphertext-Policy Attribute based Encryption (CP-ABE) and I need to understand how a secret key looks like.

For example, assume that the universe of attributes is defined to be {A,B,C,D} and user 1 receives a secret key (SK) to attributes {A,B} such that: A="NY" and B="Computer". My question is: Does SK have a certain structure or is it a bit-string? More specifically: - Does it leak the name of attributes the user have (in this case A and B)? - Does it leak information about "NY" and "Computer"? - If I generate another secret key for attributes A, B and C, can I distinguish between the two secret keys by just looking at them?

$\endgroup$
  • $\begingroup$ Are you talking about a specific implementation of CP-ABE? Generally the secret key contains the name of the attribute and its corresponding value in a retrievable format. Regarding your last question, yes because of the above. $\endgroup$ – Artjom B. Nov 20 '14 at 17:07
  • 1
    $\begingroup$ Keep in mind that you generally cannot determine who is the owner of those keys, because they may have been delegated and re-randomized, if that is what you're after. You would need some kind of traceability for that. $\endgroup$ – Artjom B. Nov 20 '14 at 17:10

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.