paper: Minor corrections for submission
This commit is contained in:
parent
7a3bcc5489
commit
af41cb2a27
2 changed files with 18 additions and 19 deletions
|
|
@ -250,7 +250,7 @@
|
|||
@Book{iaea2011,
|
||||
author = {{{International Atomic Energy Agency}}},
|
||||
date = {2011},
|
||||
title = {Safeguards, techniques and equipmen.},
|
||||
title = {Safeguards, techniques and equipment},
|
||||
isbn = {978-92-0-118910-3},
|
||||
series = {International Nuclear Verification Series},
|
||||
url = {https://www-pub.iaea.org/MTCD/Publications/PDF/nvs1_web.pdf},
|
||||
|
|
|
|||
|
|
@ -47,8 +47,8 @@
|
|||
\maketitle
|
||||
|
||||
\begin{abstract}
|
||||
In this paper, we introduce a novel countermeasure against physical attacks: Inertial hardware security modules
|
||||
(iHSMs). Conventional systems have in common that their security requires the crafting of fine sensor structures
|
||||
In this paper, we introduce a novel countermeasure against physical attacks: Inertial Hardware Security Modules
|
||||
(IHSMs). Conventional systems have in common that their security requires the crafting of fine sensor structures
|
||||
that respond to minute manipulations of the monitored security boundary or volume. Our approach is novel in that we
|
||||
reduce the sensitivity requirement of security meshes and other sensors and increase the complexity of any
|
||||
manipulations by rotating the security mesh or sensor at high speed---thereby presenting a moving target to an
|
||||
|
|
@ -136,7 +136,7 @@ detection.
|
|||
HSMs are an old technology that traces back decades in its electronic realization. Today's common approach of monitoring
|
||||
meandering electrical traces on a fragile foil that is wrapped around the HSM essentially transforms the security
|
||||
problem into the challenge to manufacture very fine electrical traces on a flexible foil~\cite{isaacs2013, immler2019,
|
||||
anderson2020}. There has been some research on monitoring the HSM's inside using e.g.\ electromagnetic
|
||||
anderson2020}. There has been some research on monitoring the HSM's interior using e.g.\ electromagnetic
|
||||
radiation~\cite{tobisch2020, kreft2012} or ultrasound~\cite{vrijaldenhoven2004} but none of this research has found
|
||||
widespread adoption yet.
|
||||
|
||||
|
|
@ -161,15 +161,14 @@ reading, similar to an HSM. They are constructed from two components: A cable th
|
|||
monitoring device. The monitoring device itself is in effect an HSM and uses a security mesh foil such as it is used in
|
||||
commercial HSMs.
|
||||
|
||||
In~\cite{anderson2020}, Anderson gives a comprehensive overview on physical security. An example HSM that they cite is
|
||||
the IBM 4758 HSM whose details are laid out in depth in~\cite{smith1998}. This HSM is an example of an industry-standard
|
||||
construction. Although its turn of the century design is now a bit dated, the construction techniques of the physical
|
||||
security mechanisms have not evolved much in the last two decades. Besides some auxiliary temperature and radiation
|
||||
sensors to guard against attacks on the built-in SRAM memory, the module's main security barrier uses the traditional
|
||||
construction of a flexible mesh foil wrapped around the module's core. In~\cite{smith1998}, the authors state that the
|
||||
module monitors this mesh for short circuits, open circuits and conductivity. The fundamental approach to tamper
|
||||
detection and construction is similar to other commercial
|
||||
offerings~\cite{obermaier2018,drimer2008,anderson2020,isaacs2013}.
|
||||
In~\cite{anderson2020}, Anderson gives a comprehensive overview on physical security. An example HSM that he cites is
|
||||
the IBM 4758, the details of which are laid out in depth in~\cite{smith1998}. This HSM is an example of an
|
||||
industry-standard construction. Although its turn of the century design is now a bit dated, the construction techniques
|
||||
of the physical security mechanisms have not evolved much in the last two decades. Besides some auxiliary temperature
|
||||
and radiation sensors to guard against attacks on the built-in SRAM memory, the module's main security barrier uses the
|
||||
common construction of a flexible mesh foil wrapped around the module's core. In~\cite{smith1998}, the authors state
|
||||
that the module monitors this mesh for short circuits, open circuits and conductivity. Other commercial offerings use a
|
||||
fundamentally similar approach to tamper detection~\cite{obermaier2018,drimer2008,anderson2020,isaacs2013}.
|
||||
|
||||
Shifting our focus from industry use to the academic state of the art, in~\cite{immler2019}, Immler et al. describe an
|
||||
HSM based on precise capacitance measurements of a security mesh, creating a PUF from the mesh. In contrast to
|
||||
|
|
@ -388,9 +387,9 @@ rotation, at the point where the shaft penetrates the mesh. The mesh's tangentia
|
|||
and the shaft itself may allow an attacker to insert tools such as probes into the device through the opening it
|
||||
creates. This issue is related to the issue conventional HSMs also face with their power and data connections. In
|
||||
conventional HSMs, power and data are routed into the enclosure through the PCB or flat flex cables sandwiched in
|
||||
between security mesh foil layers~\cite{smith1998}. In traditional HSMs this interface rarely is a mechanical weak spot
|
||||
since they use a thin mesh substrate and create a meandering path by folding the interconnect substrate/security mesh
|
||||
layers several times. In inertial HSMs, careful engineering is necessary to achieve the same effect.
|
||||
between security mesh foil layers~\cite{smith1998}. In conventional HSMs this interface rarely is a mechanical weak
|
||||
spot since they use a thin mesh substrate and create a meandering path by folding the interconnect substrate/security
|
||||
mesh layers several times. In inertial HSMs, careful engineering is necessary to achieve the same effect.
|
||||
Figure~\ref{shaft_cm} shows variations of the shaft interface with increasing complexity.
|
||||
|
||||
\begin{figure}
|
||||
|
|
@ -669,8 +668,8 @@ Figure~\ref{fig-acc-theory} shows a plot of our measurement results against freq
|
|||
blue, and theoretical behavior is shown in orange. From our measurements we can conclude that an accelerometer is a good
|
||||
choice for an IHSM's braking sensor. A simple threshold set according to the sensor's calculated expected centrifugal
|
||||
force should be sufficient to reliably detect manipulation attempts without resulting in false positives. Periodic
|
||||
controlled changes in the IHSM's speed of rotation allow an offset and scale calibration of the accelerometer on the
|
||||
fly, without stopping the rotor.
|
||||
controlled changes in the IHSM's speed of rotation allow offset and scale calibration of the accelerometer on the fly,
|
||||
without stopping the rotor.
|
||||
|
||||
\begin{figure}
|
||||
\center
|
||||
|
|
@ -707,7 +706,7 @@ fly, without stopping the rotor.
|
|||
\section{Conclusion}
|
||||
\label{sec_conclusion}
|
||||
|
||||
In this paper we introduced Inertial Hardware Security Modules (iHSMs), a novel concept for the construction of advanced
|
||||
In this paper we introduced Inertial Hardware Security Modules (IHSMs), a novel concept for the construction of advanced
|
||||
hardware security modules from simple components. We analyzed the concept for its security properties and highlighted
|
||||
its ability to significantly strengthen otherwise weak tamper detection barriers. We validated our design by creating a
|
||||
proof of concept hardware prototype. In this prototype we have demonstrated practical solutions to the major electronics
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue