Files
lattigo/circuits/integer/circuits_bfv_test.go
2023-09-12 11:23:46 +02:00

396 lines
12 KiB
Go

package integer
import (
"encoding/json"
"flag"
"fmt"
"math"
"math/big"
"runtime"
"testing"
"github.com/stretchr/testify/require"
"github.com/tuneinsight/lattigo/v4/bfv"
"github.com/tuneinsight/lattigo/v4/bgv"
"github.com/tuneinsight/lattigo/v4/ring"
"github.com/tuneinsight/lattigo/v4/rlwe"
"github.com/tuneinsight/lattigo/v4/utils"
"github.com/tuneinsight/lattigo/v4/utils/bignum"
"github.com/tuneinsight/lattigo/v4/utils/sampling"
)
var flagPrintNoise = flag.Bool("print-noise", false, "print the residual noise")
var flagParamString = flag.String("params", "", "specify the test cryptographic parameters as a JSON string. Overrides -short.")
func GetTestName(opname string, p bgv.Parameters, lvl int) string {
return fmt.Sprintf("%s/LogN=%d/logQ=%d/logP=%d/logT=%d/Qi=%d/Pi=%d/lvl=%d",
opname,
p.LogN(),
int(math.Round(p.LogQ())),
int(math.Round(p.LogP())),
int(math.Round(p.LogT())),
p.QCount(),
p.PCount(),
lvl)
}
var (
// These parameters are for test purpose only and are not 128-bit secure.
testInsecure = bgv.ParametersLiteral{
LogN: 10,
Q: []uint64{0x3fffffa8001, 0x1000090001, 0x10000c8001, 0x10000f0001, 0xffff00001},
P: []uint64{0x7fffffd8001},
}
testPlaintextModulus = []uint64{0x101, 0xffc001}
testParams = []bgv.ParametersLiteral{testInsecure}
)
func TestBFV(t *testing.T) {
var err error
paramsLiterals := testParams
if *flagParamString != "" {
var jsonParams bgv.ParametersLiteral
if err = json.Unmarshal([]byte(*flagParamString), &jsonParams); err != nil {
t.Fatal(err)
}
paramsLiterals = []bgv.ParametersLiteral{jsonParams} // the custom test suite reads the parameters from the -params flag
}
for _, p := range paramsLiterals[:] {
for _, plaintextModulus := range testPlaintextModulus[:] {
p.PlaintextModulus = plaintextModulus
params, err := bfv.NewParametersFromLiteral(bfv.ParametersLiteral(p))
require.NoError(t, err)
tc, err := genTestParams(params)
require.NoError(t, err)
for _, testSet := range []func(tc *testContext, t *testing.T){
testLinearTransformation,
} {
testSet(tc, t)
runtime.GC()
}
}
}
}
func testLinearTransformation(tc *testContext, t *testing.T) {
level := tc.params.MaxLevel()
t.Run(GetTestName("Evaluator/LinearTransform/BSGS=true", bgv.Parameters(tc.params.Parameters), level), func(t *testing.T) {
params := tc.params
values, _, ciphertext := newBFVTestVectorsLvl(level, tc.params.DefaultScale(), tc, tc.encryptorSk)
diagonals := make(Diagonals[uint64])
totSlots := values.N()
diagonals[-15] = make([]uint64, totSlots)
diagonals[-4] = make([]uint64, totSlots)
diagonals[-1] = make([]uint64, totSlots)
diagonals[0] = make([]uint64, totSlots)
diagonals[1] = make([]uint64, totSlots)
diagonals[2] = make([]uint64, totSlots)
diagonals[3] = make([]uint64, totSlots)
diagonals[4] = make([]uint64, totSlots)
diagonals[15] = make([]uint64, totSlots)
for i := 0; i < totSlots; i++ {
diagonals[-15][i] = 1
diagonals[-4][i] = 1
diagonals[-1][i] = 1
diagonals[0][i] = 1
diagonals[1][i] = 1
diagonals[2][i] = 1
diagonals[3][i] = 1
diagonals[4][i] = 1
diagonals[15][i] = 1
}
ltparams := LinearTransformationParameters{
DiagonalsIndexList: []int{-15, -4, -1, 0, 1, 2, 3, 4, 15},
Level: ciphertext.Level(),
Scale: tc.params.DefaultScale(),
LogDimensions: ciphertext.LogDimensions,
LogBabyStepGianStepRatio: 1,
}
// Allocate the linear transformation
linTransf := NewLinearTransformation(params, ltparams)
// Encode on the linear transformation
require.NoError(t, EncodeLinearTransformation[uint64](ltparams, tc.encoder, diagonals, linTransf))
galEls := GaloisElementsForLinearTransformation(params, ltparams)
ltEval := NewLinearTransformationEvaluator(tc.evaluator.WithKey(rlwe.NewMemEvaluationKeySet(nil, tc.kgen.GenGaloisKeysNew(galEls, tc.sk)...)))
require.NoError(t, ltEval.Evaluate(ciphertext, linTransf, ciphertext))
tmp := make([]uint64, totSlots)
copy(tmp, values.Coeffs[0])
subRing := tc.params.RingT().SubRings[0]
subRing.Add(values.Coeffs[0], utils.RotateSlotsNew(tmp, -15), values.Coeffs[0])
subRing.Add(values.Coeffs[0], utils.RotateSlotsNew(tmp, -4), values.Coeffs[0])
subRing.Add(values.Coeffs[0], utils.RotateSlotsNew(tmp, -1), values.Coeffs[0])
subRing.Add(values.Coeffs[0], utils.RotateSlotsNew(tmp, 1), values.Coeffs[0])
subRing.Add(values.Coeffs[0], utils.RotateSlotsNew(tmp, 2), values.Coeffs[0])
subRing.Add(values.Coeffs[0], utils.RotateSlotsNew(tmp, 3), values.Coeffs[0])
subRing.Add(values.Coeffs[0], utils.RotateSlotsNew(tmp, 4), values.Coeffs[0])
subRing.Add(values.Coeffs[0], utils.RotateSlotsNew(tmp, 15), values.Coeffs[0])
verifyBFVTestVectors(tc, tc.decryptor, values, ciphertext, t)
})
t.Run(GetTestName("Evaluator/LinearTransform/BSGS=false", bgv.Parameters(tc.params.Parameters), level), func(t *testing.T) {
params := tc.params
values, _, ciphertext := newBFVTestVectorsLvl(level, tc.params.DefaultScale(), tc, tc.encryptorSk)
diagonals := make(Diagonals[uint64])
totSlots := values.N()
diagonals[-15] = make([]uint64, totSlots)
diagonals[-4] = make([]uint64, totSlots)
diagonals[-1] = make([]uint64, totSlots)
diagonals[0] = make([]uint64, totSlots)
diagonals[1] = make([]uint64, totSlots)
diagonals[2] = make([]uint64, totSlots)
diagonals[3] = make([]uint64, totSlots)
diagonals[4] = make([]uint64, totSlots)
diagonals[15] = make([]uint64, totSlots)
for i := 0; i < totSlots; i++ {
diagonals[-15][i] = 1
diagonals[-4][i] = 1
diagonals[-1][i] = 1
diagonals[0][i] = 1
diagonals[1][i] = 1
diagonals[2][i] = 1
diagonals[3][i] = 1
diagonals[4][i] = 1
diagonals[15][i] = 1
}
ltparams := LinearTransformationParameters{
DiagonalsIndexList: []int{-15, -4, -1, 0, 1, 2, 3, 4, 15},
Level: ciphertext.Level(),
Scale: tc.params.DefaultScale(),
LogDimensions: ciphertext.LogDimensions,
LogBabyStepGianStepRatio: -1,
}
// Allocate the linear transformation
linTransf := NewLinearTransformation(params, ltparams)
// Encode on the linear transformation
require.NoError(t, EncodeLinearTransformation[uint64](ltparams, tc.encoder, diagonals, linTransf))
galEls := GaloisElementsForLinearTransformation(params, ltparams)
ltEval := NewLinearTransformationEvaluator(tc.evaluator.WithKey(rlwe.NewMemEvaluationKeySet(nil, tc.kgen.GenGaloisKeysNew(galEls, tc.sk)...)))
require.NoError(t, ltEval.Evaluate(ciphertext, linTransf, ciphertext))
tmp := make([]uint64, totSlots)
copy(tmp, values.Coeffs[0])
subRing := tc.params.RingT().SubRings[0]
subRing.Add(values.Coeffs[0], utils.RotateSlotsNew(tmp, -15), values.Coeffs[0])
subRing.Add(values.Coeffs[0], utils.RotateSlotsNew(tmp, -4), values.Coeffs[0])
subRing.Add(values.Coeffs[0], utils.RotateSlotsNew(tmp, -1), values.Coeffs[0])
subRing.Add(values.Coeffs[0], utils.RotateSlotsNew(tmp, 1), values.Coeffs[0])
subRing.Add(values.Coeffs[0], utils.RotateSlotsNew(tmp, 2), values.Coeffs[0])
subRing.Add(values.Coeffs[0], utils.RotateSlotsNew(tmp, 3), values.Coeffs[0])
subRing.Add(values.Coeffs[0], utils.RotateSlotsNew(tmp, 4), values.Coeffs[0])
subRing.Add(values.Coeffs[0], utils.RotateSlotsNew(tmp, 15), values.Coeffs[0])
verifyBFVTestVectors(tc, tc.decryptor, values, ciphertext, t)
})
t.Run("PolyEval", func(t *testing.T) {
polyEval := NewPolynomialEvaluator(tc.params.Parameters, tc.evaluator.Evaluator, true)
t.Run("Single", func(t *testing.T) {
if tc.params.MaxLevel() < 4 {
t.Skip("MaxLevel() to low")
}
values, _, ciphertext := newBFVTestVectorsLvl(tc.params.MaxLevel(), tc.params.NewScale(1), tc, tc.encryptorSk)
coeffs := []uint64{1, 2, 3, 4, 5, 6, 7, 8}
T := tc.params.PlaintextModulus()
for i := range values.Coeffs[0] {
values.Coeffs[0][i] = ring.EvalPolyModP(values.Coeffs[0][i], coeffs, T)
}
poly := bignum.NewPolynomial(bignum.Monomial, coeffs, nil)
res, err := polyEval.Evaluate(ciphertext, poly, tc.params.DefaultScale()) // TODO simpler interface for BFV ?
require.NoError(t, err)
require.True(t, res.Scale.Cmp(tc.params.DefaultScale()) == 0)
verifyBFVTestVectors(tc, tc.decryptor, values, res, t)
})
t.Run("Vector", func(t *testing.T) {
if tc.params.MaxLevel() < 4 {
t.Skip("MaxLevel() to low")
}
values, _, ciphertext := newBFVTestVectorsLvl(tc.params.MaxLevel(), tc.params.NewScale(7), tc, tc.encryptorSk)
coeffs0 := []uint64{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}
coeffs1 := []uint64{2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17}
slots := values.N()
slotIndex := make(map[int][]int)
idx0 := make([]int, slots>>1)
idx1 := make([]int, slots>>1)
for i := 0; i < slots>>1; i++ {
idx0[i] = 2 * i
idx1[i] = 2*i + 1
}
slotIndex[0] = idx0
slotIndex[1] = idx1
polyVector, err := NewPolynomialVector([][]uint64{
coeffs0,
coeffs1,
}, slotIndex)
require.NoError(t, err)
TInt := new(big.Int).SetUint64(tc.params.PlaintextModulus())
for pol, idx := range slotIndex {
for _, i := range idx {
values.Coeffs[0][i] = polyVector.Value[pol].EvaluateModP(new(big.Int).SetUint64(values.Coeffs[0][i]), TInt).Uint64()
}
}
res, err := polyEval.Evaluate(ciphertext, polyVector, tc.params.DefaultScale())
require.NoError(t, err)
require.True(t, res.Scale.Cmp(tc.params.DefaultScale()) == 0)
verifyBFVTestVectors(tc, tc.decryptor, values, res, t)
})
})
}
type testContext struct {
params bfv.Parameters
ringQ *ring.Ring
ringT *ring.Ring
prng sampling.PRNG
uSampler *ring.UniformSampler
encoder *bgv.Encoder
kgen *rlwe.KeyGenerator
sk *rlwe.SecretKey
pk *rlwe.PublicKey
encryptorPk *rlwe.Encryptor
encryptorSk *rlwe.Encryptor
decryptor *rlwe.Decryptor
evaluator *bfv.Evaluator
testLevel []int
}
func genTestParams(params bfv.Parameters) (tc *testContext, err error) {
tc = new(testContext)
tc.params = params
if tc.prng, err = sampling.NewPRNG(); err != nil {
return nil, err
}
tc.ringQ = params.RingQ()
tc.ringT = params.RingT()
tc.uSampler = ring.NewUniformSampler(tc.prng, tc.ringT)
tc.kgen = bfv.NewKeyGenerator(tc.params)
tc.sk, tc.pk = tc.kgen.GenKeyPairNew()
tc.encoder = bgv.NewEncoder(bgv.Parameters(tc.params.Parameters))
tc.encryptorPk = bfv.NewEncryptor(tc.params, tc.pk)
tc.encryptorSk = bfv.NewEncryptor(tc.params, tc.sk)
tc.decryptor = bfv.NewDecryptor(tc.params, tc.sk)
tc.evaluator = bfv.NewEvaluator(tc.params, rlwe.NewMemEvaluationKeySet(tc.kgen.GenRelinearizationKeyNew(tc.sk)))
tc.testLevel = []int{0, params.MaxLevel()}
return
}
func newBFVTestVectorsLvl(level int, scale rlwe.Scale, tc *testContext, encryptor *rlwe.Encryptor) (coeffs ring.Poly, plaintext *rlwe.Plaintext, ciphertext *rlwe.Ciphertext) {
coeffs = tc.uSampler.ReadNew()
for i := range coeffs.Coeffs[0] {
coeffs.Coeffs[0][i] = uint64(i)
}
plaintext = bfv.NewPlaintext(tc.params, level)
plaintext.Scale = scale
tc.encoder.Encode(coeffs.Coeffs[0], plaintext)
if encryptor != nil {
var err error
ciphertext, err = encryptor.EncryptNew(plaintext)
if err != nil {
panic(err)
}
}
return coeffs, plaintext, ciphertext
}
func verifyBFVTestVectors(tc *testContext, decryptor *rlwe.Decryptor, coeffs ring.Poly, element rlwe.ElementInterface[ring.Poly], t *testing.T) {
coeffsTest := make([]uint64, tc.params.MaxSlots())
switch el := element.(type) {
case *rlwe.Plaintext:
require.NoError(t, tc.encoder.Decode(el, coeffsTest))
case *rlwe.Ciphertext:
pt := decryptor.DecryptNew(el)
require.NoError(t, tc.encoder.Decode(pt, coeffsTest))
if *flagPrintNoise {
require.NoError(t, tc.encoder.Encode(coeffsTest, pt))
ct, err := tc.evaluator.SubNew(el, pt)
require.NoError(t, err)
vartmp, _, _ := rlwe.Norm(ct, decryptor)
t.Logf("STD(noise): %f\n", vartmp)
}
default:
t.Fatal("invalid test object to verify")
}
require.True(t, utils.EqualSlice(coeffs.Coeffs[0], coeffsTest))
}