mirror of
https://github.com/luxfi/lattice.git
synced 2026-09-24 00:25:44 +00:00
zeekay
eaf864890e
- Update module path to github.com/luxfi/lattice/v7 - Add GPU acceleration with Metal (macOS) and CUDA backends - Enhance threshold FHE operations - Revert to vanilla Apache 2.0 license (remove tfhe) - Update Go version to 1.25.5 - Merge upstream lattigo improvements
69 lines
1.7 KiB
Go
69 lines
1.7 KiB
Go
package bootstrapping
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import (
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"github.com/luxfi/lattice/v7/core/rlwe"
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"github.com/luxfi/lattice/v7/schemes/ckks"
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"github.com/luxfi/lattice/v7/utils/bignum"
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)
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// SecretKeyBootstrapper is an implementation of the [rlwe.Bootstrapping] interface that
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// uses the secret-key to decrypt and re-encrypt the bootstrapped ciphertext.
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type SecretKeyBootstrapper struct {
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ckks.Parameters
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*ckks.Encoder
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*rlwe.Decryptor
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*rlwe.Encryptor
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sk *rlwe.SecretKey
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Counter int // records the number of bootstrapping
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MinLevel int
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}
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func NewSecretKeyBootstrapper(params ckks.Parameters, sk *rlwe.SecretKey) *SecretKeyBootstrapper {
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return &SecretKeyBootstrapper{
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Parameters: params,
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Encoder: ckks.NewEncoder(params),
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Decryptor: rlwe.NewDecryptor(params, sk),
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Encryptor: rlwe.NewEncryptor(params, sk),
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sk: sk,
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}
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}
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func (d *SecretKeyBootstrapper) Bootstrap(ct *rlwe.Ciphertext) (*rlwe.Ciphertext, error) {
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values := make([]*bignum.Complex, 1<<ct.LogDimensions.Cols)
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if err := d.Decode(d.DecryptNew(ct), values); err != nil {
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return nil, err
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}
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pt := ckks.NewPlaintext(d.Parameters, d.MaxLevel())
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pt.MetaData = ct.MetaData
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pt.Scale = d.Parameters.DefaultScale()
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if err := d.Encode(values, pt); err != nil {
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return nil, err
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}
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ct.Resize(1, d.MaxLevel())
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d.Counter++
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return ct, d.Encrypt(pt, ct)
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}
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func (d SecretKeyBootstrapper) BootstrapMany(cts []rlwe.Ciphertext) ([]rlwe.Ciphertext, error) {
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for i := range cts {
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ct, err := d.Bootstrap(&cts[i])
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if err != nil {
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return nil, err
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}
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cts[i] = *ct
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}
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return cts, nil
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}
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func (d SecretKeyBootstrapper) Depth() int {
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return 0
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}
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func (d SecretKeyBootstrapper) MinimumInputLevel() int {
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return d.MinLevel
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}
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func (d SecretKeyBootstrapper) OutputLevel() int {
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return d.MaxLevel()
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}
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