Hardware Reference
In-Depth Information
As another example, let us consider the case of an error detection mechanism
(EDM). The detection is only possible when an error is activated. It is based either
on the direct observation of an alteration of the dynamic state:
8
t;
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;
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(8.6)
or via the explicit sensitization (e.g., via a specific test program) of a an erroneous
static state and on the observation of the resulting modification of the dynamic
state:
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I
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(8.7)
8.3.2
The Fault Injection Techniques
Numerous injection techniques have been proposed (
Benso and Prinetto
,
2003
)
,
ranging classically from (1) simulation-based techniques at various levels of rep-
resentation of the target system (physical, logical, RTL, PMS, etc.), (2) hardware-
implemented techniques (
HWIFI
, for short), e.g., pin-level injection, heavy-ion
radiation, laser injection, EMI, power supply alteration, etc., and (3) software-
implemented fault injection (also known as
SWIFI
) techniques that are meant to
corrupt the execution of a software program either at compile time (code mutation)
or at run time. In particular, the latter supports the bit-flip model in register/memory
elements. Many tools were developed to facilitate experiments based on these
techniques.
Most of the work on fault injection focused on the injection of faults/errors in-
tended to “mimic” the consequences of hardware faults (stuck-at, opens, bridging,
logical inversion, bit-flips, voltage spikes, etc.). Only during the past decade, several
efforts were devoted to the analysis of software faults. Indeed, besides the SWIFI
technique was primarily targeting hardware faults, the erroneous behaviors that can
be provoked by applying this technique can also simulate (to some extent) the
consequences of software faults (
Duraes and Madeira
2006
;
Crouzet et al.
2006
)
.
A typical branch of work on this area concerns the investigation of dependability
benchmarks aimed at characterizing the robustness of software executives, e.g., mi-
crokernels, OSs, middleware
(
Kanoun and Spainhower
2008
). More recently, some
studies addressed the analysis of cryptographic circuits with respect to malicious
attacks targeting potential vulnerabilities including also side channels procured by
scan chain test devices (
Hely et al.
2005
), as well as via fault injection applied to
Due to the context of this topic, we focus on typical techniques targeting hard-
ware faults. Hereafter, we emphasize the four injection techniques - heavy-ion
radiation, pin-level injection, electromagnetic interferences, as well as a compile-
time SWIFI - that were applied in the multi-site cooperative work carried out in
the late 1990s in the framework of the ESPRIT PDCS project. The objective was
