QR ⇒ TDH

Standard model · DGI+19

Statement

QR implies trapdoor hash functions for the index predicates $f_i(x)=x_i$ with one-bit hints: for every index $i$, an encoding key hides $i$, and its trapdoor recovers $x_i$ from the hash $H(x)$ and the hint — DGI+19.