1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136

use concrete_commons::parameters::PlaintextCount;

use crate::backends::core::implementation::engines::CoreEngine;
use crate::backends::core::implementation::entities::{
    GlweCiphertext32, GlweCiphertext64, GlweSecretKey32, GlweSecretKey64, PlaintextVector32,
    PlaintextVector64,
};
use crate::backends::core::private::crypto::encoding::PlaintextList as ImplPlaintextList;
use crate::specification::engines::{
    GlweCiphertextDecryptionEngine, GlweCiphertextDecryptionError,
};
use crate::specification::entities::GlweSecretKeyEntity;

/// # Description:
/// Implementation of [`GlweCiphertextDecryptionEngine`] for [`CoreEngine`] that operates on 32 bits
/// integers.
impl GlweCiphertextDecryptionEngine<GlweSecretKey32, GlweCiphertext32, PlaintextVector32>
    for CoreEngine
{
    /// # Example:
    /// ```
    /// use concrete_commons::dispersion::Variance;
    /// use concrete_commons::parameters::{GlweDimension, PolynomialSize};
    /// use concrete_core::prelude::*;
    /// # use std::error::Error;
    ///
    /// # fn main() -> Result<(), Box<dyn Error>> {
    /// // DISCLAIMER: the parameters used here are only for test purpose, and are not secure.
    /// let glwe_dimension = GlweDimension(2);
    /// let polynomial_size = PolynomialSize(4);
    /// // Here a hard-set encoding is applied (shift by 20 bits)
    /// let input = vec![3_u32 << 20; polynomial_size.0];
    /// let noise = Variance(2_f64.powf(-25.));
    ///
    /// let mut engine = CoreEngine::new()?;
    /// let key: GlweSecretKey32 = engine.create_glwe_secret_key(glwe_dimension, polynomial_size)?;
    /// let plaintext_vector = engine.create_plaintext_vector(&input)?;
    /// let ciphertext = engine.encrypt_glwe_ciphertext(&key, &plaintext_vector, noise)?;
    ///
    /// let decrypted_plaintext_vector = engine.decrypt_glwe_ciphertext(&key, &ciphertext)?;
    /// #
    /// assert_eq!(
    /// #     decrypted_plaintext_vector.plaintext_count(),
    /// #     plaintext_vector.plaintext_count()
    /// # );
    ///
    /// engine.destroy(key)?;
    /// engine.destroy(plaintext_vector)?;
    /// engine.destroy(ciphertext)?;
    /// engine.destroy(decrypted_plaintext_vector)?;
    /// #
    /// # Ok(())
    /// # }
    /// ```
    fn decrypt_glwe_ciphertext(
        &mut self,
        key: &GlweSecretKey32,
        input: &GlweCiphertext32,
    ) -> Result<PlaintextVector32, GlweCiphertextDecryptionError<Self::EngineError>> {
        GlweCiphertextDecryptionError::perform_generic_checks(key, input)?;
        Ok(unsafe { self.decrypt_glwe_ciphertext_unchecked(key, input) })
    }

    unsafe fn decrypt_glwe_ciphertext_unchecked(
        &mut self,
        key: &GlweSecretKey32,
        input: &GlweCiphertext32,
    ) -> PlaintextVector32 {
        let mut plaintext =
            ImplPlaintextList::allocate(0u32, PlaintextCount(key.polynomial_size().0));
        key.0.decrypt_glwe(&mut plaintext, &input.0);
        PlaintextVector32(plaintext)
    }
}

/// # Description:
/// Implementation of [`GlweCiphertextDecryptionEngine`] for [`CoreEngine`] that operates on 64 bits
/// integers.
impl GlweCiphertextDecryptionEngine<GlweSecretKey64, GlweCiphertext64, PlaintextVector64>
    for CoreEngine
{
    /// # Example:
    /// ```
    /// use concrete_commons::dispersion::Variance;
    /// use concrete_commons::parameters::{GlweDimension, PolynomialSize};
    /// use concrete_core::prelude::*;
    /// # use std::error::Error;
    ///
    /// # fn main() -> Result<(), Box<dyn Error>> {
    /// // DISCLAIMER: the parameters used here are only for test purpose, and are not secure.
    /// let glwe_dimension = GlweDimension(2);
    /// let polynomial_size = PolynomialSize(4);
    /// // Here a hard-set encoding is applied (shift by 50 bits)
    /// let input = vec![3_u64 << 50; polynomial_size.0];
    /// let noise = Variance(2_f64.powf(-25.));
    ///
    /// let mut engine = CoreEngine::new()?;
    /// let key: GlweSecretKey64 = engine.create_glwe_secret_key(glwe_dimension, polynomial_size)?;
    /// let plaintext_vector = engine.create_plaintext_vector(&input)?;
    /// let ciphertext = engine.encrypt_glwe_ciphertext(&key, &plaintext_vector, noise)?;
    ///
    /// let decrypted_plaintext_vector = engine.decrypt_glwe_ciphertext(&key, &ciphertext)?;
    /// #
    /// assert_eq!(
    /// #     decrypted_plaintext_vector.plaintext_count(),
    /// #     plaintext_vector.plaintext_count()
    /// # );
    ///
    /// engine.destroy(key)?;
    /// engine.destroy(plaintext_vector)?;
    /// engine.destroy(ciphertext)?;
    /// engine.destroy(decrypted_plaintext_vector)?;
    /// #
    /// # Ok(())
    /// # }
    /// ```
    fn decrypt_glwe_ciphertext(
        &mut self,
        key: &GlweSecretKey64,
        input: &GlweCiphertext64,
    ) -> Result<PlaintextVector64, GlweCiphertextDecryptionError<Self::EngineError>> {
        GlweCiphertextDecryptionError::perform_generic_checks(key, input)?;
        Ok(unsafe { self.decrypt_glwe_ciphertext_unchecked(key, input) })
    }

    unsafe fn decrypt_glwe_ciphertext_unchecked(
        &mut self,
        key: &GlweSecretKey64,
        input: &GlweCiphertext64,
    ) -> PlaintextVector64 {
        let mut plaintext =
            ImplPlaintextList::allocate(0u64, PlaintextCount(key.polynomial_size().0));
        key.0.decrypt_glwe(&mut plaintext, &input.0);
        PlaintextVector64(plaintext)
    }
}