aboutsummaryrefslogtreecommitdiff
path: root/slides/2018-lwm/src/body.tex
diff options
context:
space:
mode:
Diffstat (limited to 'slides/2018-lwm/src/body.tex')
-rw-r--r--slides/2018-lwm/src/body.tex268
1 files changed, 268 insertions, 0 deletions
diff --git a/slides/2018-lwm/src/body.tex b/slides/2018-lwm/src/body.tex
new file mode 100644
index 0000000..67f3c5e
--- /dev/null
+++ b/slides/2018-lwm/src/body.tex
@@ -0,0 +1,268 @@
+\begin{frame}
+ \frametitle{Certificate Transparency (CT)}
+ \begin{columns}
+ \begin{column}{0.49\textwidth}
+ \begin{itemize}
+ \item Add transparency to CA ecosystem
+ \item Publicly log all certificates
+ \item No need\footnotemark{} to trust the log
+ \begin{itemize}
+ \item Membership proofs
+ \item Append-only proofs
+ \end{itemize}
+ \end{itemize}
+ \end{column}
+ \begin{column}{0.49\textwidth}
+ \centering
+ \includegraphics[width=\textwidth]{img/ct}
+ \burl{http://www.certificate-transparency.org/what-is-ct}
+ \end{column}
+ \end{columns}
+ \footnotetext{As deployed right now we do trust the logs tho \Frowny}
+\end{frame}
+
+\begin{frame}
+ \frametitle{Certificate logging in greater detail
+ \titlefloatright{Merkle tree}}
+ \centering
+ \vfill
+ \input{img/mt}
+ \pause
+ \vfill
+ \begin{columns}
+ \begin{column}{0.49\textwidth}
+ \begin{itemize}
+ \item Append new certificates in batches
+ \end{itemize}
+ \end{column}
+ \begin{column}{0.49\textwidth}
+ \begin{itemize}
+ \item Sign tree head every hour \ding{224} STH
+ \end{itemize}
+ \end{column}
+ \end{columns}
+ \vfill
+ %\vfill\centering\alert{Anyone can audit and monitor the log, but as deployed
+ % not much of this yet}
+\end{frame}
+
+\begin{frame}
+ \frametitle{Generating a membership proof
+ \titlefloatright{Audit path}}
+ \centering
+ \vfill
+ \input{img/mtp}
+ \vfill
+ \begin{columns}
+ \begin{column}{0.49\textwidth}
+ \begin{itemize}
+ \item Traverse tree from root to leaf
+ \end{itemize}
+ \end{column}
+ \begin{column}{0.49\textwidth}
+ \begin{itemize}
+ \item Grab all sibling hashes on the way
+ \end{itemize}
+ \end{column}
+ \end{columns}
+ \vfill
+\end{frame}
+
+\begin{frame}
+ \frametitle{Two approaches towards monitoring a CT log}
+ \begin{columns}
+ \begin{column}{0.49\textwidth}
+ \centering
+ \vbox to 0.8\textheight {
+ \textbf{Self-monitoring}
+ \vfill
+ \input{img/self-monitor}
+ \vfill
+ \pause
+ \begin{description}
+ \item[\Frowny] Continuous uptime
+ \item[\Frowny] Download everything
+ \end{description}
+ \pause
+ }
+ \end{column}
+ \begin{column}{0.49\textwidth}
+ \centering
+ \vbox to 0.8\textheight {
+ \textbf{Monitoring-as-a-service}
+ \vfill
+ \input{img/tp-monitor}
+ \pause
+ \vfill
+ \begin{description}
+ \item[\Smiley] Ezpz
+ \item[\Frowny] Trusted 3rd party
+ \end{description}
+ }
+ \end{column}
+ \end{columns}
+\end{frame}
+
+\begin{frame}
+ \frametitle{Notion of what we would like to achieve
+ \titlefloatright{`Wish list'}}
+ \begin{columns}
+ \begin{column}{0.59\textwidth}
+ \begin{itemize}
+ \item CT/bis backwards compatibility
+ \item Piggy-back on gossip-audit model
+ \item Self-monitor wildcards w/o full download
+ \item Reduced 3rd party monitoring trust
+ \end{itemize}
+ \end{column}
+ \begin{column}{0.39\textwidth}
+ \centering
+ \includegraphics[height=0.8\textheight]{img/wish}
+ \end{column}
+ \end{columns}
+\end{frame}
+
+\begin{frame}
+ \frametitle{An overview of light-weight monitoring}
+ \centering
+ \input{img/overview}
+ \vfill
+ \begin{columns}
+ \begin{column}{0.49\textwidth}
+ \begin{itemize}
+ \item A new Merkle tree for each batch
+ \end{itemize}
+ \end{column}
+ \begin{column}{0.49\textwidth}
+ \begin{itemize}
+ \item Add snapshot to STH as extension
+ \end{itemize}
+ \end{column}
+ \end{columns}
+ \vfill\centering\alert{One wildcard (non-)membership notification per STH}\\
+ \pause
+ \alert{How do you know if you got all notifications \ding{224} index
+ extension}
+\end{frame}
+
+\begin{frame}
+ \frametitle{Wildcard notifications}
+ \centering
+ \input{img/wildcard}
+ \begin{columns}
+ \begin{column}{0.39\textwidth}
+ \begin{itemize}
+ \item Merkleize reverse-sorted list
+ \end{itemize}
+ \end{column}
+ \begin{column}{0.59\textwidth}
+ \begin{itemize}
+ \item Wildcard proof \ding{224} at most two audit paths
+ \end{itemize}
+ \end{column}
+ \end{columns}
+ \pause
+ \vfill\centering\alert{Security of this data structure? It is still just a
+ Merkle tree...}
+\end{frame}
+
+\begin{frame}
+ \frametitle{Performance evaluation \titlefloatright{Experimental setup}}
+ \begin{columns}
+ \begin{column}{0.49\textwidth}
+ \vbox to .6\textheight{
+ \begin{itemize}
+ \item PoC: 351 lines of Go\footnotemark
+ \item Interesting metrics
+ \begin{itemize}
+ \item Snapshot creation time
+ \item Proof generation time
+ \item Proof verification time
+ \item Bandwidth overhead
+ \end{itemize}
+ \item Two log characteristics that matter
+ \begin{itemize}
+ \item STH frequency
+ \item Batch size
+ \end{itemize}
+ \end{itemize}
+ \vfill\centering\alert{We observed all Chrome-included logs for eight
+ months to determine these characteristics}
+ }
+ \end{column}
+ \begin{column}{0.49\textwidth}
+ \vbox to 0.8\textheight{
+ \centering
+ \vfill
+ \textbf{Google's Icarus Log}\\
+ \vfill
+ \includegraphics[width=\textwidth]{img/frequency}\\
+ \vfill
+ \includegraphics[width=\textwidth]{img/batch}
+ \vfill
+ }
+ \end{column}
+ \end{columns}
+ \footnotetext{\burl{https://github.com/rgdd/lwm}}
+\end{frame}
+
+\begin{frame}
+ \frametitle{Snapshot creation time}
+ \centering
+ \includegraphics[height=0.6\textheight]{img/snapshot}
+ \vfill\centering\alert{Negligible in comparison to STH issuance rate (1h)}
+\end{frame}
+
+\begin{frame}
+ \frametitle{Proof generation time}
+ \centering
+ \includegraphics[height=0.6\textheight]{img/proofgen}
+ \vfill\centering\alert{At least 288M non-membership proofs per hour on a
+ single core}
+\end{frame}
+
+\begin{frame}
+ \frametitle{Proof generation and verification for *.com}
+ \centering
+ \includegraphics[height=0.6\textheight]{img/proofcom}
+ \vfill\centering\alert{352k matches in max batch \ding{224} 29k proofs per
+ hour on a single core}
+\end{frame}
+
+\begin{frame}
+ \frametitle{Bandwidth overhead}
+ \begin{columns}
+ \begin{column}{0.69\textwidth}
+ \begin{description}
+ \item[Audit paths] max batch size \ding{224} 1 KB
+ \item[Self-monitor] compare to median batch size of 32.6 MB
+ \item[Notifier] 288M audit paths per hour \ding{224} 640 Mbps
+ \end{description}
+ \end{column}
+ \begin{column}{0.39\textwidth}
+ \centering\includegraphics[width=\textwidth]{img/perf}
+ \burl{http://blog.coviam.com/wp-content/uploads/2016/07/Performance-Evaluation-Process-z.jpg}
+ \end{column}
+ \end{columns}
+\end{frame}
+
+\begin{frame}
+ \frametitle{Take away}
+ \begin{columns}
+ \begin{column}{0.79\textwidth}
+ \begin{itemize}
+ \item Unfortunate if CT monitoring relies on trusted parties
+ \item Light-weight monitoring
+ \begin{itemize}
+ \item One verifiable wildcard notification per batch
+ \item Untrusted notification component with push/pull model
+ \item Untrusted log \ding{224} rely on one honest monitor
+ \item Trusted log \ding{224} no need to also trust monitor
+ \end{itemize}
+ \end{itemize}
+ \end{column}
+ \begin{column}{0.19\textwidth}
+ \centering\includegraphics[width=\textwidth]{img/takeaway}
+ \end{column}
+ \end{columns}
+\end{frame}