Skip to content

Commit

Permalink
Fixed CI and updated slides
Browse files Browse the repository at this point in the history
  • Loading branch information
rasmus-kirk committed Jan 31, 2025
1 parent 35a5f0d commit 3ba3e27
Show file tree
Hide file tree
Showing 2 changed files with 93 additions and 13 deletions.
27 changes: 15 additions & 12 deletions flake.lock

Some generated files are not rendered by default. Learn more about how customized files appear on GitHub.

79 changes: 78 additions & 1 deletion slides/slides.md
Original file line number Diff line number Diff line change
Expand Up @@ -224,7 +224,84 @@ As for the $\ASDLDecider$, it just runs $\PCDLCheck$ on the provided
accumulator, which represents a evaluation proof i.e. an instance. This
check will always pass, as the prover constructed it honestly.

## Soundness proof
## Soundness proof (1/?)

Let $\CM = (\CMSetup, \CMCommit)$ be a perfectly binding commitment scheme. Fix
a maximum degree $D \in \Nb$ and a random oracle $\rho$ that takes commitments
from $\CM$ to $F_\pp$. Then for every family of functions $\{f_\pp\}_\pp$
and fields $\{F_\pp\}_\pp$ where:

- $f_\pp \in \Mc \to F_\pp^{\leq D}[X]$
- $F \in \Nb \to \Nb$
- $|F_\pp| \geq F(\l)$

That is, for all functions, $f_\pp$, that takes a message, $\Mc$ as input and
outputs a maximum D-degree polynomial. Also, usually $|F_\pp| \approx F(\l)$.
For every message format $L$ and computationally unbounded $t$-query oracle
algorithm $\Ac$, the following holds:
$$
\Pr\left[
\begin{array}{c}
p \neq 0 \\
\land \\
p(z) = 0
\end{array}
\middle|
\begin{array}{c}
\rho \from \mathcal{U}(\l) \\
\pp_\CM \gets \CMSetup(1^\l, L) \\
(m, \omega) \gets \Ac^\rho(\pp_\CM) \\
C \gets \CMCommit(m, \o) \\
z \in F_{\pp} \from \rho(C) \\
p := f_{\pp}(m)
\end{array}
\right] \leq \sqrt{\frac{D(t+1)}{F(\l)}}
$$

## Soundness proof (1/?)

$$
\Pr \left[
\begin{array}{c}
\ASDLVerifier^{\rho_1}((q_{\acc_{i-1}} \cat \vec{q}), \acc_i) = \top, \\
\ASDLDecider^{\rho_1}(\acc_i) = \top \\
\land \\
\exists i \in [n] : \Phi_\AS(q_i) = \bot
\end{array}
\right] \leq \negl(\l)
$$
Given:
$$
\begin{alignedat}{4}
&\rho_0 &&\leftarrow \Uc(\l), &&\quad \rho_1 &&\leftarrow \Uc(\l), \\
&\pp_\PC &&\leftarrow \PCDLSetup^{\rho_0}(1^\l, D), &&\quad \pp_\AS &&\leftarrow \ASDLSetup^{\rho_1}(1^\l, \pp_\PC), \\
&(\vec{q}, \acc_{i-1}, \acc_i) &&\leftarrow \Ac^{\rho_1}(\pp_\AS, \pp_\PC), &&\quad q_{acc_{i-1}} &&\leftarrow \ToInstance(\acc_{i-1})
\end{alignedat}
$$

- We call the probability that the adversary $\Ac$ wins the above game
$\d$. We bound $\d$ by constructing two adversaries, $\Bc_1, \Bc_2$, for
the zero-finding game. Assuming:
- $\Pr[\Bc_1 \text{ wins} \lor \Bc_2 \text{wins}] = \delta - \negl(\l)$
- $\Pr[\Bc_1 \text{ wins} \lor \Bc_2 \text{wins}] = 0$

## Soundness Proof (3/?)


$$
\begin{aligned}
\Pr[\Bc_1 \text{ wins} \lor \Bc_2 \text{ wins}] &= \Pr[\Bc_1 \text{ wins}] + \Pr[\Bc_2\text{ wins}] - \Pr[\Bc_1 \text{ wins} \land \Bc_2 \text{ wins}]\\
\Pr[\Bc_1 \text{ wins} \lor \Bc_2 \text{ wins}] &= \Pr[\Bc_1 \text{ wins}] + \Pr[\Bc_2\text{ wins}] - 0 \\
\delta - \negl(\l) &\leq \sqrt{\frac{D(t+1)}{F(\l)}} + \sqrt{\frac{D(t+1)}{F(\l)}} \\
\delta - \negl(\l) &\leq 2 \cdot \sqrt{\frac{D(t+1)}{|\Fb_q|}} \\
\delta &\leq 2 \cdot \sqrt{\frac{D(t+1)}{|\Fb_q|}} + \negl(\l) \\
\end{aligned}
$$

Meaning that $\delta$ is negligible, since $q = |\Fb_q|$ is superpolynomial
in $\l$.

## Soundness Proof (3/?)

## Efficiency analysis

Expand Down

0 comments on commit 3ba3e27

Please sign in to comment.