Add Dlog' ggm proof

This commit is contained in:
2023-05-09 10:01:01 +02:00
parent 8a7b0d4d75
commit 56f6c785bb
9 changed files with 280 additions and 8 deletions

View File

@@ -26,6 +26,7 @@ This section shows that \somdl implies MU-\igame using the Algebraic Group Model
\vspace{2mm}
\begin{algorithmic}[1]
\Statex \underline{\oracle $DL(i \in \{1,2,...,N\})$}
\vspace{1mm}
\State $I \assign I + 1$
\State \Return $a_i$
\end{algorithmic}
@@ -146,7 +147,7 @@ This section shows that \somdl implies MU-\igame using the Algebraic Group Model
\Leftrightarrow \groupelement{A} &= (2^c s^* - r_b)(r_i + 2^c \ch^*)^{-1} \groupelement{B}
\end{align*}
Assuming that $r_i + 2^c \ch^*$ is invertible in $\field{L}$ (i.e. not equal to 0), which is ensured by the abort in $G_2$ for all $i$, both equations can be used to calculate the discrete logarithm if $A_i$. Together with the discrete logarithms of the other public keys, which where obtained by the \textit{DL} oracle, the adversary $\adversary{B}$ is able to craft a valid solution for the \somdl challenger.
Assuming that $r_i + 2^c \ch^*$ is invertible in $\field{L}$ (i.e., not equal to 0), which is ensured by the abort in $G_2$ for all $i$, both equations can be used to calculate the discrete logarithm of $A_i$. Together with the discrete logarithms of the other public keys, which were obtained by the \textit{DL} oracle, the adversary $\adversary{B}$ is able to craft a valid solution for the \somdl challenger.
\item This proves theorem \ref{theorem:adv_omdl'}.
\end{proof}