Tamper and Leakage
Resilience in the Split-State Model
Feng-Hao Liu (
Anna Lysyanskaya (
Abstract:
It is notoriously difficult to create hardware that is immune from side
channel and tampering attacks. A lot of recent literature, therefore, has
instead considered algorithmic defenses from such attacks.
In this paper, we show how to algorithmically secure any cryptographic
functionality from continual split-state leakage and tampering attacks. A
split-state attack on cryptographic hardware is one that targets separate
parts of the hardware separately. Our construction does not require the hardware
to have access to randomness. In contrast, prior work on protecting from
continual combined leakage and tampering [KalaiKS11] required true randomness
for each update. Our construction is in the common reference string (CRS)
model; the CRS must be hard-wired into the device. We note that prior
negative results show that it is impossible to algorithmically secure a
cryptographic functionality against a combination of arbitrary continual
leakage and tampering attacks without true randomness; therefore restricting
our attention to the split-state model is justified.
Our construction is simple and modular, and relies on a new construction, in
the CRS model, of non-malleable codes with respect to split-state tampering
functions, which may be of independent interest.