Céline Chevalier, Stéphanie Delaune, and Steve Kremer. Transforming Password Protocols to Compose. In Proceedings of the 31st Conference on Foundations of Software Technology and Theoretical Computer Science (FSTTCS'11), pp. 204–216, Leibniz International Proceedings in Informatics 13, Leibniz-Zentrum für Informatik, Mumbai, India, December 2011.
Formal, symbolic techniques are extremely useful for modelling and analysing security protocols. They improved our understanding of security protocols, allowed to discover flaws, and also provide support for protocol design. However, such analyses usually consider that the protocol is executed in isolation or assume a bounded number of protocol sessions. Hence, no security guarantee is provided when the protocol is executed in a more complex environment.
In this paper, we study whether password protocols can be safely composed, even when a same password is reused. More precisely, we present a transformation which maps a password protocol that is secure for a single protocol session (a decidable problem) to a protocol that is secure for an unbounded number of sessions. Our result provides an effective strategy to design secure password protocols: (i) design a protocol intended to be secure for one protocol session; (ii) apply our transformation and obtain a protocol which is secure for an unbounded number of sessions. Our technique also applies to compose different password protocols allowing us to obtain both inter-protocol and inter-session composition.
@inproceedings{CDK-fsttcs11,
abstract = {Formal, symbolic techniques are extremely useful for
modelling and analysing security protocols. They
improved our understanding of security protocols,
allowed to discover flaws, and also provide support
for protocol design. However, such analyses usually
consider that the protocol is executed in isolation
or assume a bounded number of protocol sessions.
Hence, no security guarantee is provided when the
protocol is executed in a more complex
environment.\par In this paper, we study whether
password protocols can be safely composed, even when
a same password is reused. More precisely, we present
a transformation which maps a password protocol that
is secure for a single protocol session (a~decidable
problem) to a protocol that is secure for an
unbounded number of sessions. Our result provides an
effective strategy to design secure password
protocols: (i)~design a protocol intended to be
secure for one protocol session; (ii)~apply our
transformation and obtain a protocol which is secure
for an unbounded number of sessions. Our technique
also applies to compose different password protocols
allowing us to obtain both inter-protocol and
inter-session composition.},
address = {Mumbai, India},
author = {Chevalier, C{\'e}line and Delaune, St{\'e}phanie and
Kremer, Steve},
booktitle = {{P}roceedings of the 31st {C}onference on
{F}oundations of {S}oftware {T}echnology and
{T}heoretical {C}omputer {S}cience ({FSTTCS}'11)},
OPTDOI = {10.4230/LIPIcs.FSTTCS.2011.204},
editor = {Chakraborty, Supratik and Kumar, Amit},
month = dec,
pages = {204-216},
publisher = {Leibniz-Zentrum f{\"u}r Informatik},
series = {Leibniz International Proceedings in Informatics},
title = {Transforming Password Protocols to Compose},
volume = {13},
year = {2011},
acceptrate = {37/116},
acronym = {{FSTTCS}'11},
nmonth = {12},
OPTLONGPDF = {http://www.lsv.ens-cachan.fr/Publis/RAPPORTS_LSV/PDF/
rr-lsv-2011-21.pdf},
lsv-category = {intc},
wwwpublic = {public and ccsb},
}