TY - GEN

T1 - On the (Im)possibility of key dependent encryption

AU - Haitner, Iftach

AU - Holenstein, Thomas

PY - 2009

Y1 - 2009

N2 - We study the possibility of constructing encryption schemes secure under messages that are chosen depending on the key k of the encryption scheme itself. We give the following separation results that hold both in the private and in the public key settings: Let be the family of poly(n)-wise independent hash-functions. There exists no fully-black-box reduction from an encryption scheme secure against key-dependent messages to one-way permutations (and also to families of trapdoor permutations) if the adversary can obtain encryptions of h(k) for . There exists no reduction from an encryption scheme secure against key-dependent messages to, essentially, any cryptographic assumption, if the adversary can obtain an encryption of g(k) for an arbitrary g, as long as the reduction's proof of security treats both the adversary and the function g as black boxes.

AB - We study the possibility of constructing encryption schemes secure under messages that are chosen depending on the key k of the encryption scheme itself. We give the following separation results that hold both in the private and in the public key settings: Let be the family of poly(n)-wise independent hash-functions. There exists no fully-black-box reduction from an encryption scheme secure against key-dependent messages to one-way permutations (and also to families of trapdoor permutations) if the adversary can obtain encryptions of h(k) for . There exists no reduction from an encryption scheme secure against key-dependent messages to, essentially, any cryptographic assumption, if the adversary can obtain an encryption of g(k) for an arbitrary g, as long as the reduction's proof of security treats both the adversary and the function g as black boxes.

KW - Black-box separations

KW - Key-dependent input

KW - One-way functions

UR - http://www.scopus.com/inward/record.url?scp=70350634168&partnerID=8YFLogxK

U2 - 10.1007/978-3-642-00457-5_13

DO - 10.1007/978-3-642-00457-5_13

M3 - ???researchoutput.researchoutputtypes.contributiontobookanthology.conference???

AN - SCOPUS:70350634168

SN - 3642004563

SN - 9783642004568

T3 - Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)

SP - 202

EP - 219

BT - Theory of Cryptography - 6th Theory of Cryptography Conference, TCC 2009, Proceedings

T2 - 6th Theory of Cryptography Conference, TCC 2009

Y2 - 15 March 2009 through 17 March 2009

ER -