Method decrypt

saver/src/encryption.rs:289–299

Decrypt the given ciphertext and return the message and a "commitment" to randomness to help in verifying the decryption without knowledge of secret key. This is "Dec" from algorithm 2 in the paper

(
        c_0: &E::G1Affine,
        c: &[E::G1Affine],
        sk: &SecretKey<E::ScalarField>,
        dk: impl Into<PreparedDecryptionKey<E>>,
        g_i: &[E::G1Affine],
        chunk_bit_size: u8

    /// Decrypt the given ciphertext and return the message and a "commitment" to randomness to help in
    /// verifying the decryption without knowledge of secret key. This is "Dec" from algorithm 2 in the paper
    pub fn decrypt(
        c_0: &E::G1Affine,
        c: &[E::G1Affine],
        sk: &SecretKey<E::ScalarField>,
        dk: impl Into<PreparedDecryptionKey<E>>,
        g_i: &[E::G1Affine],
        chunk_bit_size: u8,
    ) -> crate::Result<(E::ScalarField, E::G1Affine)> {
        let (chunks, nu) = Self::decrypt_to_chunks(c_0, c, sk, dk, g_i, chunk_bit_size)?;
        Ok((utils::compose(&chunks, chunk_bit_size)?, nu))
    }

    /// Same as `Self::decrypt` but expects pairing powers (see `PreparedDecryptionKey::pairing_powers`)
    /// that can be precomputed for even faster decryption