期刊名称:Electronic Colloquium on Computational Complexity
印刷版ISSN:1433-8092
出版年度:1999
卷号:1999
出版社:Universität Trier, Lehrstuhl für Theoretische Computer-Forschung
摘要:We study the security of individual bits in an
RSA encrypted message EN(x). We show that given EN(x),
predicting any single bit in x with only a non-negligible
advantage over the trivial guessing strategy, is (through a
polynomial time reduction) as hard as breaking RSA\@. Moreover, we
prove that blocks of O(loglogN) bits of x are
computationally indistinguishable from random bits. The results
carry over to the Rabin encryption scheme.
Considering the discrete exponentiation function gx modulo p, with
probability 1−o(1) over random choices of the prime p, the
analog results are demonstrated. Finally, we prove that the
bits of ax+b modulo p give hard core predicates for any one-way
function f.