imported from https://bitbucket.org/ustraca/crypto

thresholdkey_test.go

@@ -0,0 +1,369 @@
+package paillier
+
+import (
+	"crypto/rand"
+	"math/big"
+	"reflect"
+	"testing"
+)
+
+func GetThresholdPrivateKey() *ThresholdPrivateKey {
+	tkh := GetThresholdKeyGenerator(32, 10, 6, rand.Reader)
+	tpks, err := tkh.Generate()
+	if err != nil {
+		panic(err)
+	}
+	return tpks[6]
+}
+
+func TestDelta(t *testing.T) {
+	tk := new(ThresholdKey)
+	tk.TotalNumberOfDecryptionServers = 6
+	if delta := tk.Delta(); 720 != n(delta) {
+		t.Error("Delta is not 720 but", delta)
+	}
+}
+
+func TestCombineSharesConstant(t *testing.T) {
+	tk := new(ThresholdKey)
+	tk.N = big.NewInt(101 * 103)
+	tk.TotalNumberOfDecryptionServers = 6
+
+	if c := tk.CombineSharesConstant(); !reflect.DeepEqual(big.NewInt(4558), c) {
+		t.Error("wrong combined key.  ", c)
+	}
+}
+
+func TestDecrypt(t *testing.T) {
+	key := new(ThresholdPrivateKey)
+	key.TotalNumberOfDecryptionServers = 10
+	key.N = b(101 * 103)
+	key.Share = b(862)
+	key.Id = 9
+	c := b(56)
+
+	partial := key.Decrypt(c)
+
+	if partial.Id != 9 {
+		t.Fail()
+	}
+	if n(partial.Decryption) != 40644522 {
+		t.Error("wrong decryption ", partial.Decryption)
+	}
+}
+
+func TestCopyVi(t *testing.T) {
+	key := new(ThresholdPrivateKey)
+	key.Vi = []*big.Int{b(34), b(2), b(29)}
+	vi := key.copyVi()
+	if !reflect.DeepEqual(vi, key.Vi) {
+		t.Fail()
+	}
+	key.Vi[1] = b(89)
+	if reflect.DeepEqual(vi, key.Vi) {
+		t.Fail()
+	}
+}
+
+func TestEncryptWithThresholdKey(t *testing.T) {
+	pd := GetThresholdPrivateKey()
+	_, err := pd.Encrypt(big.NewInt(876), rand.Reader)
+	if err != nil {
+		t.Fail()
+	}
+}
+
+func TestDecryptWithThresholdKey(t *testing.T) {
+	pd := GetThresholdPrivateKey()
+	c, err := pd.Encrypt(big.NewInt(876), rand.Reader)
+	if err != nil {
+		t.Fail()
+	}
+	pd.Decrypt(c.C)
+}
+
+func TestVerifyPart1(t *testing.T) {
+	pd := new(PartialDecryptionZKP)
+	pd.Key = new(ThresholdKey)
+	pd.Key.N = b(131)
+	pd.Decryption = b(101)
+	pd.C = b(99)
+	pd.E = b(112)
+	pd.Z = b(88)
+
+	if a := pd.verifyPart1(); n(a) != 11986 {
+		t.Error("wrong a ", a)
+	}
+}
+
+func TestVerifyPart2(t *testing.T) {
+	pd := new(PartialDecryptionZKP)
+	pd.Key = new(ThresholdKey)
+	pd.Id = 1
+	pd.Key.Vi = []*big.Int{b(77), b(67)} // vi is 67
+	pd.Key.N = b(131)
+	pd.Key.V = b(101)
+	pd.E = b(112)
+	pd.Z = b(88)
+	if b := pd.verifyPart2(); n(b) != 14602 {
+		t.Error("wrong b ", b)
+	}
+}
+
+func TestDecryptAndProduceZNP(t *testing.T) {
+	pd := GetThresholdPrivateKey()
+	c, err := pd.Encrypt(big.NewInt(876), rand.Reader)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	znp, err := pd.DecryptAndProduceZNP(c.C, rand.Reader)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+
+	if !znp.Verify() {
+		t.Fail()
+	}
+}
+
+func TestMakeVerificationBeforeCombiningPartialDecryptions(t *testing.T) {
+	tk := new(ThresholdKey)
+	tk.Threshold = 2
+	if tk.MakeVerificationBeforeCombiningPartialDecryptions([]*PartialDecryption{}) == nil {
+		t.Fail()
+	}
+	prms := []*PartialDecryption{new(PartialDecryption), new(PartialDecryption)}
+	prms[1].Id = 1
+	if tk.MakeVerificationBeforeCombiningPartialDecryptions(prms) != nil {
+		t.Fail()
+	}
+	prms[1].Id = 0
+	if tk.MakeVerificationBeforeCombiningPartialDecryptions(prms) == nil {
+		t.Fail()
+	}
+}
+
+func TestUpdateLambda(t *testing.T) {
+	tk := new(ThresholdKey)
+	lambda := b(11)
+	share1 := &PartialDecryption{3, b(5)}
+	share2 := &PartialDecryption{7, b(3)}
+	res := tk.UpdateLambda(share1, share2, lambda)
+	if n(res) != 20 {
+		t.Error("wrong lambda", n(res))
+	}
+}
+
+func TestupdateCprime(t *testing.T) {
+	tk := new(ThresholdKey)
+	tk.N = b(99)
+	cprime := b(77)
+	lambda := b(52)
+	share := &PartialDecryption{3, b(5)}
+	cprime = tk.updateCprime(cprime, lambda, share)
+	if n(cprime) != 8558 {
+		t.Error("wrong cprime", cprime)
+	}
+
+}
+
+func TestEncryptingDecryptingSimple(t *testing.T) {
+	tkh := GetThresholdKeyGenerator(10, 2, 1, rand.Reader)
+	tpks, err := tkh.Generate()
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	message := b(100)
+	c, err := tpks[1].Encrypt(message, rand.Reader)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	share1 := tpks[0].Decrypt(c.C)
+	message2, err := tpks[0].CombinePartialDecryptions([]*PartialDecryption{share1})
+	if err != nil {
+		t.Error(err)
+	}
+	if n(message) != n(message2) {
+		t.Error("decrypted message is not the same one than the input one ", message2)
+	}
+}
+
+func TestEncryptingDecrypting(t *testing.T) {
+	tkh := GetThresholdKeyGenerator(10, 2, 2, rand.Reader)
+	tpks, err := tkh.Generate()
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	message := b(100)
+	c, err := tpks[1].Encrypt(message, rand.Reader)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	share1 := tpks[0].Decrypt(c.C)
+	share2 := tpks[1].Decrypt(c.C)
+	message2, err := tpks[0].CombinePartialDecryptions([]*PartialDecryption{share1, share2})
+	if err != nil {
+		t.Error(err)
+	}
+	if n(message) != n(message2) {
+		t.Error("The decrypted cyphered is not original massage but ", message2)
+	}
+}
+
+func TestDecryption(t *testing.T) {
+	// test the correct decryption of '100'.
+	share1 := &PartialDecryption{1, b(384111638639)}
+	share2 := &PartialDecryption{2, b(235243761043)}
+	tk := new(ThresholdKey)
+	tk.Threshold = 2
+	tk.TotalNumberOfDecryptionServers = 2
+	tk.N = b(637753)
+	tk.G = b(637754)
+	tk.V = b(70661107826)
+	if msg, err := tk.CombinePartialDecryptions([]*PartialDecryption{share1, share2}); err != nil {
+		t.Error(err)
+	} else if n(msg) != 100 {
+		t.Error("decrypted message was not 100 but ", msg)
+	}
+
+}
+
+func TestDivide(t *testing.T) {
+	tk := new(ThresholdKey)
+	if r := tk.divide(b(77), b(4)); n(r) != 19 {
+		t.Error("77 / 4 != 19 ( ", r, " )")
+	}
+	if r := tk.divide(b(-77), b(-4)); n(r) != 19 {
+		t.Error("-77 / -4 != 19 ( ", r, " )")
+	}
+	if r := tk.divide(b(-77), b(4)); n(r) != -19 {
+		t.Error("-77 / 4 != -19 ( ", r, " )")
+	}
+	if r := tk.divide(b(77), b(-4)); n(r) != -19 {
+		t.Error("77 / -4 != -19 ( ", r, " )")
+	}
+}
+
+func TestValidate(t *testing.T) {
+	pk := GetThresholdPrivateKey()
+	if err := pk.Validate(rand.Reader); err != nil {
+		t.Error(err)
+	}
+	pk.Id++
+	if err := pk.Validate(rand.Reader); err == nil {
+		t.Fail()
+	}
+}
+
+func TestCombinePartialDecryptionsZKP(t *testing.T) {
+	tkh := GetThresholdKeyGenerator(10, 2, 2, rand.Reader)
+	tpks, err := tkh.Generate()
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	message := b(100)
+	c, err := tpks[1].Encrypt(message, rand.Reader)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	share1, err := tpks[0].DecryptAndProduceZNP(c.C, rand.Reader)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	share2, err := tpks[1].DecryptAndProduceZNP(c.C, rand.Reader)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	message2, err := tpks[0].CombinePartialDecryptionsZKP([]*PartialDecryptionZKP{share1, share2})
+	if err != nil {
+		t.Error(err)
+	}
+	if n(message) != n(message2) {
+		t.Error("The decrypted cyphered is not original massage but ", message2)
+	}
+	share1.E = b(687687678)
+	_, err = tpks[0].CombinePartialDecryptionsZKP([]*PartialDecryptionZKP{share1, share2})
+	if err == nil {
+		t.Fail()
+	}
+}
+
+func TestCombinePartialDecryptionsWith100Shares(t *testing.T) {
+	tkh := GetThresholdKeyGenerator(10, 100, 50, rand.Reader)
+	tpks, err := tkh.Generate()
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	message := b(100)
+	c, err := tpks[1].Encrypt(message, rand.Reader)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	shares := make([]*PartialDecryption, 75)
+	for i := 0; i < 75; i++ {
+		shares[i] = tpks[i].Decrypt(c.C)
+	}
+
+	message2, err := tpks[0].CombinePartialDecryptions(shares)
+	if err != nil {
+		t.Error(err)
+	}
+	if n(message) != n(message2) {
+		t.Error("The decrypted cyphered is not original massage but ", message2)
+	}
+}
+
+func TestVerifyDecryption(t *testing.T) {
+	tkh := GetThresholdKeyGenerator(10, 2, 2, rand.Reader)
+	tpks, err := tkh.Generate()
+
+	pk := &tpks[0].ThresholdKey
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	expt := b(101)
+	cypher, err := tpks[0].Encrypt(expt, rand.Reader)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	pd1, err := tpks[0].DecryptAndProduceZNP(cypher.C, rand.Reader)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	pd2, err := tpks[1].DecryptAndProduceZNP(cypher.C, rand.Reader)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	pds := []*PartialDecryptionZKP{pd1, pd2}
+	if err != nil {
+		t.Error(err)
+		return
+	}
+
+	if err = pk.VerifyDecryption(cypher.C, b(101), pds); err != nil {
+		t.Error(err)
+	}
+	if err = pk.VerifyDecryption(cypher.C, b(100), pds); err == nil {
+		t.Error(err)
+	}
+	if err = pk.VerifyDecryption(new(big.Int).Add(b(1), cypher.C), b(101), pds); err == nil {
+		t.Error(err)
+	}
+
+}