# Lattice-Based DAPS and Generalizations: Self-enforcement in Signature Schemes

**Authors:**

*D. Boneh, S. Kim, and V. Nikolaenko*

** Abstract: **

Double authentication preventing signatures (DAPS) is a
mechanism, due to Poettering and Stebila, for protecting certificate
authorities (CAs) from coercion. We construct the first lattice-based
DAPS signatures, thereby providing the first post-quantum DAPS system.
We go further and generalize DAPS to a more general mechanism we
call predicate authentication preventing signatures (PAPS). Here, for
a given k-ary predicate φ, a PAPS system for φ is regular signature
scheme. However, if the signer ever signs k messages m_{1}, …, m_{k} such that
φ(m_{1}, … , m_{k}) is true then these k signatures reveal the signerâ€™s secret
key. This self-enforcement mechanism incentivizes the signer to never sign
conflicting messages, namely messages that satisfy the predicate φ. The
k conflicting messages can be signed at different times and the signatures
may be generated independently of one another. We further generalize
to the case when the signatures are generated by multiple signers. We
motivate these primitives, give precise definitions, and provide several
constructions. These primitives are challenging to construct and give rise
to many new elegant open research questions.

** Reference:**

In proceedings of ACNS 2017, pp. 457-477.

**Full paper:**
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