poulpy-core 0.5.0

A backend agnostic crate implementing RLWE-based encryption & arithmetic.
Documentation
use poulpy_hal::{
    api::{ScratchAvailable, SvpPPolBytesOf, VecZnxAutomorphism},
    layouts::{Backend, DataMut, GaloisElement, Module, Scratch},
    source::Source,
};

use crate::{
    GGLWEEncryptSk, ScratchTakeCore,
    layouts::{
        GGLWEInfos, GGLWEToMut, GGLWEToRef, GLWEAutomorphismKey, GLWEInfos, GLWESecret, GLWESecretPrepared,
        GLWESecretPreparedFactory, GLWESecretToRef, LWEInfos, SetGaloisElement,
    },
};

impl GLWEAutomorphismKey<Vec<u8>> {
    pub fn encrypt_sk_tmp_bytes<M, A, BE: Backend>(module: &M, infos: &A) -> usize
    where
        A: GGLWEInfos,
        M: GLWEAutomorphismKeyEncryptSk<BE>,
    {
        module.glwe_automorphism_key_encrypt_sk_tmp_bytes(infos)
    }

    pub fn encrypt_pk_tmp_bytes<M, A, BE: Backend>(module: &M, infos: &A) -> usize
    where
        A: GGLWEInfos,
        M: GLWEAutomorphismKeyEncryptPk<BE>,
    {
        module.glwe_automorphism_key_encrypt_pk_tmp_bytes(infos)
    }
}

impl<DM: DataMut> GLWEAutomorphismKey<DM>
where
    Self: GGLWEToRef,
{
    pub fn encrypt_sk<S, M, BE: Backend>(
        &mut self,
        module: &M,
        p: i64,
        sk: &S,
        source_xa: &mut Source,
        source_xe: &mut Source,
        scratch: &mut Scratch<BE>,
    ) where
        S: GLWESecretToRef,
        M: GLWEAutomorphismKeyEncryptSk<BE>,
    {
        module.glwe_automorphism_key_encrypt_sk(self, p, sk, source_xa, source_xe, scratch);
    }
}

pub trait GLWEAutomorphismKeyEncryptSk<BE: Backend> {
    fn glwe_automorphism_key_encrypt_sk_tmp_bytes<A>(&self, infos: &A) -> usize
    where
        A: GGLWEInfos;

    fn glwe_automorphism_key_encrypt_sk<R, S>(
        &self,
        res: &mut R,
        p: i64,
        sk: &S,
        source_xa: &mut Source,
        source_xe: &mut Source,
        scratch: &mut Scratch<BE>,
    ) where
        R: GGLWEToMut + SetGaloisElement + GGLWEInfos,
        S: GLWESecretToRef;
}

impl<BE: Backend> GLWEAutomorphismKeyEncryptSk<BE> for Module<BE>
where
    Self: GGLWEEncryptSk<BE> + VecZnxAutomorphism + GaloisElement + SvpPPolBytesOf + GLWESecretPreparedFactory<BE>,
    Scratch<BE>: ScratchTakeCore<BE>,
{
    fn glwe_automorphism_key_encrypt_sk_tmp_bytes<A>(&self, infos: &A) -> usize
    where
        A: GGLWEInfos,
    {
        assert_eq!(
            infos.rank_in(),
            infos.rank_out(),
            "rank_in != rank_out is not supported for GGLWEAutomorphismKey"
        );
        assert_eq!(self.n() as u32, infos.n());

        let lvl_0: usize = GLWESecretPrepared::bytes_of_from_infos(self, infos);
        let lvl_1_encrypt: usize = self.gglwe_encrypt_sk_tmp_bytes(infos);
        let lvl_1_sk: usize = GLWESecret::bytes_of_from_infos(infos);
        let lvl_1: usize = lvl_1_encrypt.max(lvl_1_sk);

        lvl_0 + lvl_1
    }

    fn glwe_automorphism_key_encrypt_sk<R, S>(
        &self,
        res: &mut R,
        p: i64,
        sk: &S,
        source_xa: &mut Source,
        source_xe: &mut Source,
        scratch: &mut Scratch<BE>,
    ) where
        R: GGLWEToMut + SetGaloisElement + GGLWEInfos,
        S: GLWESecretToRef,
    {
        let sk: &GLWESecret<&[u8]> = &sk.to_ref();

        assert_eq!(res.n(), sk.n());
        assert_eq!(res.rank_out(), res.rank_in());
        assert_eq!(sk.rank(), res.rank_out());
        assert!(
            scratch.available() >= self.glwe_automorphism_key_encrypt_sk_tmp_bytes(res),
            "scratch.available(): {} < GLWEAutomorphismKeyEncryptSk::glwe_automorphism_key_encrypt_sk_tmp_bytes: {}",
            scratch.available(),
            self.glwe_automorphism_key_encrypt_sk_tmp_bytes(res)
        );

        let (mut sk_out_prepared, scratch_1) = scratch.take_glwe_secret_prepared(self, sk.rank());

        {
            let (mut sk_out, _) = scratch_1.take_glwe_secret(sk.n(), sk.rank());
            sk_out.dist = sk.dist;

            for i in 0..sk.rank().into() {
                self.vec_znx_automorphism(
                    self.galois_element_inv(p),
                    &mut sk_out.data.as_vec_znx_mut(),
                    i,
                    &sk.data.as_vec_znx(),
                    i,
                );
            }
            sk_out_prepared.prepare(self, &sk_out);
        }

        self.gglwe_encrypt_sk(res, &sk.data, &sk_out_prepared, source_xa, source_xe, scratch_1);

        res.set_p(p);
    }
}

pub trait GLWEAutomorphismKeyEncryptPk<BE: Backend> {
    fn glwe_automorphism_key_encrypt_pk_tmp_bytes<A>(&self, infos: &A) -> usize
    where
        A: GGLWEInfos;
}

impl<BE: Backend> GLWEAutomorphismKeyEncryptPk<BE> for Module<BE>
where
    Self:,
    Scratch<BE>: ScratchTakeCore<BE>,
{
    fn glwe_automorphism_key_encrypt_pk_tmp_bytes<A>(&self, _infos: &A) -> usize
    where
        A: GGLWEInfos,
    {
        unimplemented!()
    }
}