jaseg/phd-thesis
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Fix broken reference

Browse source
This commit is contained in:
jaseg 2025-11-05 11:11:25 +01:00
parent 91d03d4ad2
commit d7eb668fcf
1 changed files with 21 additions and 18 deletions
Download patch file Download diff file Expand all files Collapse all files

39
chapter-ihsm/chapter.tex
View file

@ -83,14 +83,15 @@ detection.
HSMs are an old technology that traces back decades in its electronic realization, initially being conceived by the US HSMs are an old technology that traces back decades in its electronic realization, initially being conceived by the US
NSA during the second world war~\cite{boak1973}. Today's common approach of monitoring meandering electrical traces on a NSA during the second world war~\cite{boak1973}. 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 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, andersonSecurityEngineeringGuide2020}. There has been manufacture very fine electrical traces on a flexible foil~\cite{isaacs2013, immler2019,
some research on monitoring the HSM's interior using e.g.\ electromagnetic radiation~\cite{tobisch2020, kreft2012} or andersonSecurityEngineeringGuide2020}. There has been some research on monitoring the HSM's interior using e.g.\
ultrasound~\cite{vrijaldenhoven2004} but none of this research has found widespread adoption yet. electromagnetic radiation~\cite{tobisch2020, kreft2012} or ultrasound~\cite{vrijaldenhoven2004} but none of this
research has found widespread adoption yet.
HSMs can be compared to physical seals~\cite{andersonSecurityEngineeringGuide2020}. Both are tamper-evident devices. The difference is that an HSMs can be compared to physical seals~\cite{andersonSecurityEngineeringGuide2020}. Both are tamper-evident devices. The
HSM continuously monitors itself whereas a physical seal only serves to record tampering and requires someone to examine difference is that an HSM continuously monitors itself whereas a physical seal only serves to record tampering and
it. This examination can be done by eye in the field, but it can also be carried out in a laboratory using complex requires someone to examine it. This examination can be done by eye in the field, but it can also be carried out in a
equipment. An HSM in principle has to have this examination equipment built-in. laboratory using complex equipment. An HSM in principle has to have this examination equipment built-in.
Physical seals are used in a wide variety of applications. The most interesting ones from a research point of view that Physical seals are used in a wide variety of applications. The most interesting ones from a research point of view that
are recorded in public literature are those used for the monitoring of nuclear material under the International Atomic are recorded in public literature are those used for the monitoring of nuclear material under the International Atomic
@ -115,14 +116,16 @@ several minutes. While the state of electronics has advanced rapidly since Boak'
has not increased correspondingly. Thus, we can conclude that even today, against a ``smart, well-equipped opponent with has not increased correspondingly. Thus, we can conclude that even today, against a ``smart, well-equipped opponent with
plenty of time'' as noted by Boak, this self-destruction functionality is essential. plenty of time'' as noted by Boak, this self-destruction functionality is essential.
In~\cite{andersonSecurityEngineeringGuide2020}, Anderson gives a comprehensive overview of physical security. An example HSM that he cites is In~\cite{andersonSecurityEngineeringGuide2020}, Anderson gives a comprehensive overview of physical security. An example
the IBM 4758, the details of which are laid out in-depth in~\cite{smith1998}. This HSM is an example of an HSM that he cites is the IBM 4758, the details of which are laid out in-depth
industry-standard construction. Although its turn of the century design is now a bit dated, the construction techniques in~\cite{smithBuildingHighperformanceProgrammable1999}. This HSM is an example of an industry-standard construction.
of the physical security mechanisms have not evolved much in the last two decades. Besides some auxiliary temperature Although its turn of the century design is now a bit dated, the construction techniques of the physical security
and radiation sensors to guard against attacks on the built-in SRAM memory, the module's main security barrier uses the mechanisms have not evolved much in the last two decades. Besides some auxiliary temperature and radiation sensors to
common construction of a flexible mesh foil wrapped around the module's core. In~\cite{smith1998}, the authors state guard against attacks on the built-in SRAM memory, the module's main security barrier uses the common construction of a
that the module monitors this mesh for short circuits, open circuits, and conductivity. Other commercial offerings use flexible mesh foil wrapped around the module's core. In~\cite{smithBuildingHighperformanceProgrammable1999}, the authors
similar approaches to tamper detection~\cite{obermaier2018,drimer2008,andersonSecurityEngineeringGuide2020,isaacs2013}. state that the module monitors this mesh for short circuits, open circuits, and conductivity. Other commercial offerings
use similar approaches to tamper
detection~\cite{obermaier2018,drimer2008,andersonSecurityEngineeringGuide2020,isaacs2013}.
Shifting our focus from industry use to the academic state of the art, in~\cite{immler2019}, Immler et al. describe an 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 HSM based on precise capacitance measurements of a security mesh, creating a PUF from the mesh. In contrast to
@ -611,9 +614,9 @@ penetrates the mesh at the axis. The mesh's tangential velocity decreases close
allow an attacker to insert tools such as probes into the device through the opening it creates. Conventional HSMs also allow an attacker to insert tools such as probes into the device through the opening it creates. Conventional HSMs also
have to take precautions to protect their power and data connections. In conventional HSMs, power and data are routed have to take precautions to protect their power and data connections. In conventional HSMs, power and data are routed
into the enclosure along a meandering path through the PCB or through flat flex cables sandwiched in between security into the enclosure along a meandering path through the PCB or through flat flex cables sandwiched in between security
mesh foil layers~\cite{smith1998}. As a result of these precautions, in conventional HSMs, this interface rarely is a mesh foil layers~\cite{smithBuildingHighperformanceProgrammable1999}. As a result of these precautions, in conventional
mechanical weak spot. In inertial HSMs, careful engineering is necessary to achieve the same effect. HSMs, this interface rarely is a mechanical weak spot. In inertial HSMs, careful engineering is necessary to achieve the
Figure~\ref{shaft_cm} shows variations of the shaft interface with increasing complexity. same effect. Figure~\ref{shaft_cm} shows variations of the shaft interface with increasing complexity.
\begin{figure} \begin{figure}
\begin{subfigure}[t]{0.3\textwidth} \begin{subfigure}[t]{0.3\textwidth}