diff --git a/LICENSE b/LICENSE index a9d7db6..d3061a3 100644 --- a/LICENSE +++ b/LICENSE @@ -1,21 +1,13 @@ -MIT License +Zero-Clause BSD +============= -Copyright (c) 2022 Jude Southworth +Permission to use, copy, modify, and/or distribute this software for +any purpose with or without fee is hereby granted. -Permission is hereby granted, free of charge, to any person obtaining a copy -of this software and associated documentation files (the "Software"), to deal -in the Software without restriction, including without limitation the rights -to use, copy, modify, merge, publish, distribute, sublicense, and/or sell -copies of the Software, and to permit persons to whom the Software is -furnished to do so, subject to the following conditions: - -The above copyright notice and this permission notice shall be included in all -copies or substantial portions of the Software. - -THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR -IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, -FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE -AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER -LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, -OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE -SOFTWARE. +THE SOFTWARE IS PROVIDED “AS IS” AND THE AUTHOR DISCLAIMS ALL +WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES +OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE +FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY +DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN +AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT +OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. diff --git a/whitepaper/Dissertation.pdf b/whitepaper/Dissertation.pdf index 2c52d8c..6719236 100644 Binary files a/whitepaper/Dissertation.pdf and b/whitepaper/Dissertation.pdf differ diff --git a/whitepaper/Dissertation.tex b/whitepaper/Dissertation.tex index 9a0c436..49381a3 100644 --- a/whitepaper/Dissertation.tex +++ b/whitepaper/Dissertation.tex @@ -60,7 +60,11 @@ \chapter*{} -\section{Disambiguation} +\section*{Abstract} + +We present a modern implementation of the Paillier cryptosystem for the browser, using Jurik's form to optimise encryption. Furthermore, we present an application of this cryptosystem with zero-knowledge proofs to enable peers to maintain private state in a peer-to-peer implementation of the board game Risk. Use of novel zero-knowledge proofs enables peers to verify that the actions of other players adhere to the game's rules without learning additional information about their private state. Finally, we present benchmarks of the implementation. + +\section*{Disambiguation} \begin{table}[htp] \begin{tabularx}{\textwidth}{c X} @@ -83,7 +87,7 @@ \end{tabularx} \end{table} -\vspace*{0.1\paperheight} +\vspace*{0.05\paperheight} \begin{center} "Never create anything, it will be misinterpreted, it will chain you and follow you for the rest of your life." - Hunter S. Thompson @@ -573,7 +577,7 @@ Let $c$ be the ciphertext. The corresponding plaintext is computed as \begin{ali \subsection{Implementation details} -Paillier is implemented by four classes: \texttt{PubKey}, \texttt{PrivKey}, \texttt{Ciphertext}, and \texttt{ReadOnlyCiphertext}. \texttt{PubKey.encrypt} converts a \texttt{BigInt} into either a \texttt{Ciphertext} or a \texttt{ReadOnlyCiphertext} by the encryption function above. The distinction between these is that a \texttt{ReadOnlyCiphertext} does not know the random $r$ that was used to form it, and so is created by decrypting a ciphertext that originated with another peer. A regular \texttt{Ciphertext} maintains knowledge of $r$ and the plaintext it enciphers, which enables using \hyperref[protocol0]{Protocol~\ref*{protocol0}}. +Paillier is implemented by four classes: \texttt{PubKey}, \texttt{PrivKey}, \texttt{Ciphertext}, and \texttt{ReadOnlyCiphertext}. \texttt{PubKey.encrypt} converts a \texttt{BigInt} into either a \texttt{Ciphertext} or a \texttt{ReadOnlyCiphertext} by the encryption function above. The distinction between these is that a \texttt{ReadOnlyCiphertext} does not know the random $r$ that was used to form it, and so is created by decrypting a ciphertext that originated with another peer. A regular \texttt{Ciphertext} maintains knowledge of $r$ and the plaintext it enciphers, which is used later in \hyperref[protocol0]{Protocol~\ref*{protocol0}}. \section{Shared random values} @@ -628,7 +632,7 @@ The encryption function used must also guarantee the integrity of decrypted ciph The final value is dictated by the sum of all decrypted values. $P_n$ is therefore left in a position of choosing $N_n$ to control the outcome of $a + N_n$, where $a$ is selected uniformly at random from the abelian group $\mathbb{Z}_{2^\ell}$ for $\ell$ the agreed upon bit length. - As every element of this group is of order $2^\ell$, the distribution of $a + N_n$ is identical no matter the choice of $N_n$. So $P_n$ maintains no control over the outcome of $a + N_n$. + As every element of this group is of order $2^\ell$, the distribution of $a + N_n$ is identical regardless of the choice of $N_n$. So $P_n$ maintains no control over the outcome of $a + N_n$. \end{proof} This extends inductively to support $n-1$ cheating participants, even if colluding. Finally, we must consider how to reduce random noise to useful values. @@ -1284,7 +1288,7 @@ Using a language that can interact with the operating system would have further The P2P implementation requires more processing power and more bandwidth on each peer than a client-server implementation would. This is the main limitation of the P2P implementation. The program ran in a reasonable time, using a reasonable amount of resources on the computers I had access to, but these are not representative of the majority of computers in use today. Using greater processing power increases power consumption, which is undesirable. In a client-server implementation, the power consumption should be lower than the P2P implementation presented as no processing time is spent validating proofs or using the Paillier cryptosystem, which is less efficient than the hybrid cryptosystems used in standard online communication. -\emph{Final word count: 9,086} +\emph{Final word count: 9,088} \bibliography{Dissertation}