Struct fast_paillier::DecryptionKey

pub struct DecryptionKey { /* private fields */ }

Paillier decryption key

Implementations

impl DecryptionKey

pub fn generate(rng: &mut (impl RngCore + CryptoRng)) -> Result<Self, Error>

Generates a paillier key

Samples two safe 1536-bits primes that meets 128 bits security level

pub fn from_primes(p: Integer, q: Integer) -> Result<Self, Error>

Constructs a paillier key from primes p, q

p and q need to be safe primes sufficiently large to meet security level requirements.

Returns error if p and q do not correspond to a valid paillier key.

pub fn decrypt(&self, c: &Ciphertext) -> Result<Plaintext, Error>

Decrypts the ciphertext, returns plaintext in {-N/2, .., N_2}

pub fn encrypt_with( &self, x: &Plaintext, nonce: &Nonce ) -> Result<Ciphertext, Error>

Encrypts a plaintext x in {-N/2, .., N/2} with nonce from Z*_n

It uses the fact that factorization of N is known to speed up encryption.

Returns error if inputs are not in specified range

pub fn encrypt_with_random( &self, rng: &mut (impl RngCore + CryptoRng), x: &Plaintext ) -> Result<(Ciphertext, Nonce), Error>

Encrypts the plaintext x in {-N/2, .., N_2}

It’s uses the fact that factorization of N is known to speed up encryption.

Nonce is sampled randomly using rng.

Returns error if plaintext is not in specified range

pub fn omul( &self, scalar: &Integer, ciphertext: &Ciphertext ) -> Result<Ciphertext, Error>

Homomorphic multiplication of scalar at ciphertext

It uses the fact that factorization of N is known to speed up an operation.

omul(a, Enc(c)) = Enc(a * c)

pub fn encryption_key(&self) -> &EncryptionKey

Returns a (public) encryption key corresponding to the (secret) decryption key

pub fn n(&self) -> &Integer

The Paillier modulus

pub fn lambda(&self) -> &Integer

The Paillier lambda

pub fn mu(&self) -> &Integer

The Paillier mu

pub fn p(&self) -> &Integer

Prime p

pub fn q(&self) -> &Integer

Prime q

pub fn bits_length(&self) -> u32

Bits length of smaller prime (p or q)

Trait Implementations

impl AnyEncryptionKey for DecryptionKey

fn n(&self) -> &Integer

Returns N

fn nn(&self) -> &Integer

Returns N^2

fn half_n(&self) -> &Integer

Returns N/2

fn encrypt_with( &self, x: &Plaintext, nonce: &Nonce ) -> Result<Ciphertext, Error>

Encrypts the plaintext x in {-N/2, .., N_2} with nonce in Z*_n

fn oadd(&self, c1: &Ciphertext, c2: &Ciphertext) -> Result<Ciphertext, Error>

Homomorphic addition of two ciphertexts

fn osub(&self, c1: &Ciphertext, c2: &Ciphertext) -> Result<Ciphertext, Error>

Homomorphic subtraction of two ciphertexts

fn omul( &self, scalar: &Integer, ciphertext: &Ciphertext ) -> Result<Ciphertext, Error>

Homomorphic multiplication of scalar at ciphertext

fn oneg(&self, ciphertext: &Ciphertext) -> Result<Ciphertext, Error>

Homomorphic negation of a ciphertext

fn in_signed_group(&self, x: &Integer) -> bool

Checks whether x is {-N/2, .., N/2}

impl Clone for DecryptionKey

fn clone(&self) -> DecryptionKey

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.