  Investigating how to construct a secure hash algorithm needs in-depth study,
as various existing hash functions like the MD5 algorithm have recently exposed
their security flaws. At the same time, hash function based on chaotic theory
has become an emerging research in the field of nonlinear information security.
As an extension of our previous research works, a new chaotic iterations keyed
hash function is proposed in this article. Chaotic iterations are used both to
construct strategies with pseudorandom number generator and to calculate new
hash values using classical hash functions. It is shown that, by doing so, it
is possible to apply a kind of post-treatment on existing hash algorithms,
which preserves their security properties while adding Devaney's chaos.
Security performance analysis of such a post-treatment are finally provided.
