Identity-Based Proxy Signature with Message Recovery over NTRU Lattice

. 2023 Mar 4;25(3):454. doi: 10.3390/e25030454

Algorithm 5 Pver

1:
Compute $α = H_{2} (h z_{i + 1} + z_{i} - H_{1} (I D) H_{3} (r, u_{2}))$
2:
Compute $u_{1}^{'} = r ⨁ α$
3:
$u_{1} = | u_{1}^{'} |_{l_{2}} ⨁ F_{2} (| u_{1}^{'} |^{l_{1}})$
4:
Compute $u = u_{1} ‖ u_{2}$
5:
if $‖ (z_{i}, z_{i + 1}) ‖ \leq 2 σ \sqrt{2 N}$ , $F_{1} (u_{1}) = {| u_{1}^{'} |}^{l_{1}}$ then
6:
$Return$ 1
7:
else
8:
$Return$ 0
9:
end if