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use crate::ciphertext::RadixCiphertext;
use crate::ServerKey;
impl ServerKey {
/// Computes homomorphically a multiplication between a ciphertext encrypting an integer value
/// and another encrypting a shortint value.
///
/// This function computes the operation without checking if it exceeds the capacity of the
/// ciphertext.
///
/// The result is assigned to the `ct_left` ciphertext.
///
/// # Example
///
///```rust
/// use concrete_integer::gen_keys_radix;
/// use concrete_shortint::parameters::PARAM_MESSAGE_2_CARRY_2;
/// let size = 4;
///
/// // Generate the client key and the server key:
/// let (cks, sks) = gen_keys_radix(&PARAM_MESSAGE_2_CARRY_2, size);
///
/// let clear_1 = 170;
/// let clear_2 = 3;
///
/// // Encrypt two messages
/// let mut ct_left = cks.encrypt(clear_1);
/// let ct_right = cks.encrypt_one_block(clear_2);
///
/// // Compute homomorphically a multiplication
/// sks.unchecked_block_mul_assign(&mut ct_left, &ct_right, 0);
///
/// // Decrypt
/// let res = cks.decrypt(&ct_left);
/// assert_eq!((clear_1 * clear_2) % 256, res);
/// ```
pub fn unchecked_block_mul_assign(
&self,
ct_left: &mut RadixCiphertext,
ct_right: &concrete_shortint::Ciphertext,
index: usize,
) {
*ct_left = self.unchecked_block_mul(ct_left, ct_right, index);
}
/// Computes homomorphically a multiplication between a ciphertexts encrypting an integer
/// value and another encrypting a shortint value.
///
/// This function computes the operation without checking if it exceeds the capacity of the
/// ciphertext.
///
/// The result is returned as a new ciphertext.
///
/// # Example
///
///```rust
/// use concrete_integer::gen_keys_radix;
/// use concrete_shortint::parameters::PARAM_MESSAGE_2_CARRY_2;
/// let size = 4;
///
/// // Generate the client key and the server key:
/// let (cks, sks) = gen_keys_radix(&PARAM_MESSAGE_2_CARRY_2, size);
///
/// let clear_1 = 55;
/// let clear_2 = 3;
///
/// // Encrypt two messages
/// let ct_left = cks.encrypt(clear_1);
/// let ct_right = cks.encrypt_one_block(clear_2);
///
/// // Compute homomorphically a multiplication
/// let ct_res = sks.unchecked_block_mul(&ct_left, &ct_right, 0);
///
/// // Decrypt
/// let res = cks.decrypt(&ct_res);
/// assert_eq!((clear_1 * clear_2) % 256, res);
/// ```
pub fn unchecked_block_mul(
&self,
ct1: &RadixCiphertext,
ct2: &concrete_shortint::Ciphertext,
index: usize,
) -> RadixCiphertext {
let shifted_ct = self.blockshift(ct1, index);
let mut result_lsb = shifted_ct.clone();
let mut result_msb = shifted_ct;
for res_lsb_i in result_lsb.blocks[index..].iter_mut() {
self.key.unchecked_mul_lsb_assign(res_lsb_i, ct2);
}
let len = result_msb.blocks.len() - 1;
for res_msb_i in result_msb.blocks[index..len].iter_mut() {
self.key.unchecked_mul_msb_assign(res_msb_i, ct2);
}
result_msb = self.blockshift(&result_msb, 1);
self.unchecked_add(&result_lsb, &result_msb)
}
/// Computes homomorphically a multiplication between a ciphertext encrypting integer value
/// and another encrypting a shortint value.
///
/// The result is returned as a new ciphertext.
///
/// # Example
///
///```rust
/// use concrete_integer::gen_keys_radix;
/// use concrete_shortint::parameters::PARAM_MESSAGE_2_CARRY_2;
/// let size = 4;
///
/// // Generate the client key and the server key:
/// let (cks, sks) = gen_keys_radix(&PARAM_MESSAGE_2_CARRY_2, size);
///
/// let clear_1 = 170;
/// let clear_2 = 3;
///
/// // Encrypt two messages
/// let mut ctxt_1 = cks.encrypt(clear_1);
/// let ctxt_2 = cks.encrypt_one_block(clear_2);
///
/// // Compute homomorphically a multiplication
/// let ct_res = sks.smart_block_mul(&mut ctxt_1, &ctxt_2, 0);
///
/// // Decrypt
/// let res = cks.decrypt(&ct_res);
/// assert_eq!((clear_1 * clear_2) % 256, res);
/// ```
pub fn smart_block_mul(
&self,
ct1: &mut RadixCiphertext,
ct2: &concrete_shortint::Ciphertext,
index: usize,
) -> RadixCiphertext {
//Makes sure we can do the multiplications
self.full_propagate(ct1);
let shifted_ct = self.blockshift(ct1, index);
let mut result_lsb = shifted_ct.clone();
let mut result_msb = shifted_ct;
for res_lsb_i in result_lsb.blocks[index..].iter_mut() {
self.key.unchecked_mul_lsb_assign(res_lsb_i, ct2);
}
let len = result_msb.blocks.len() - 1;
for res_msb_i in result_msb.blocks[index..len].iter_mut() {
self.key.unchecked_mul_msb_assign(res_msb_i, ct2);
}
result_msb = self.blockshift(&result_msb, 1);
self.smart_add(&mut result_lsb, &mut result_msb)
}
pub fn smart_block_mul_assign(
&self,
ct1: &mut RadixCiphertext,
ct2: &concrete_shortint::Ciphertext,
index: usize,
) {
*ct1 = self.smart_block_mul(ct1, ct2, index);
}
/// Computes homomorphically a multiplication between two ciphertexts encrypting integer values.
///
/// This function computes the operation without checking if it exceeds the capacity of the
/// ciphertext.
///
/// The result is assigned to the `ct_left` ciphertext.
/// # Example
///
/// ```rust
/// use concrete_integer::gen_keys_radix;
/// use concrete_shortint::parameters::PARAM_MESSAGE_2_CARRY_2;
/// let size = 4;
///
/// // Generate the client key and the server key:
/// let (cks, sks) = gen_keys_radix(&PARAM_MESSAGE_2_CARRY_2, size);
///
/// let clear_1 = 255;
/// let clear_2 = 143;
///
/// // Encrypt two messages
/// let mut ctxt_1 = cks.encrypt(clear_1);
/// let ctxt_2 = cks.encrypt(clear_2);
///
/// // Compute homomorphically a multiplication
/// let ct_res = sks.unchecked_mul(&mut ctxt_1, &ctxt_2);
///
/// // Decrypt
/// let res = cks.decrypt(&ct_res);
/// assert_eq!((clear_1 * clear_2) % 256, res);
/// ```
pub fn unchecked_mul_assign(&self, ct1: &mut RadixCiphertext, ct2: &RadixCiphertext) {
*ct1 = self.unchecked_mul(ct1, ct2);
}
/// Computes homomorphically a multiplication between two ciphertexts encrypting integer values.
///
/// This function computes the operation without checking if it exceeds the capacity of the
/// ciphertext.
///
/// The result is returned as a new ciphertext.
pub fn unchecked_mul(
&self,
ct1: &mut RadixCiphertext,
ct2: &RadixCiphertext,
) -> RadixCiphertext {
let copy = ct1.clone();
let mut result = self.create_trivial_zero_radix(ct1.blocks.len());
for (i, ct2_i) in ct2.blocks.iter().enumerate() {
let tmp = self.unchecked_block_mul(©, ct2_i, i);
self.unchecked_add_assign(&mut result, &tmp);
}
result
}
/// Computes homomorphically a multiplication between two ciphertexts encrypting integer values.
///
/// The result is assigned to the `ct_left` ciphertext.
///
/// # Example
///
/// ```rust
/// use concrete_integer::gen_keys_radix;
/// use concrete_shortint::parameters::PARAM_MESSAGE_2_CARRY_2;
/// let size = 4;
///
/// // Generate the client key and the server key:
/// let (cks, sks) = gen_keys_radix(&PARAM_MESSAGE_2_CARRY_2, size);
///
/// let clear_1 = 170;
/// let clear_2 = 6;
///
/// // Encrypt two messages
/// let mut ctxt_1 = cks.encrypt(clear_1);
/// let mut ctxt_2 = cks.encrypt(clear_2);
///
/// // Compute homomorphically a multiplication
/// let ct_res = sks.smart_mul(&mut ctxt_1, &mut ctxt_2);
/// // Decrypt
/// let res = cks.decrypt(&ct_res);
/// assert_eq!((clear_1 * clear_2) % 256, res);
/// ```
pub fn smart_mul_assign(&self, ct1: &mut RadixCiphertext, ct2: &mut RadixCiphertext) {
*ct1 = self.smart_mul(ct1, ct2);
}
/// Computes homomorphically a multiplication between two ciphertexts encrypting integer values.
///
/// The result is returned as a new ciphertext.
pub fn smart_mul(
&self,
ct1: &mut RadixCiphertext,
ct2: &mut RadixCiphertext,
) -> RadixCiphertext {
self.full_propagate(ct1);
self.full_propagate(ct2);
let copy = ct1.clone();
let mut result = self.create_trivial_zero_radix(ct1.blocks.len());
for (i, ct2_i) in ct2.blocks.iter().enumerate() {
let mut tmp = self.unchecked_block_mul(©, ct2_i, i);
self.smart_add_assign(&mut result, &mut tmp);
}
result
}
}