diff --git a/LICENSE b/LICENSE
index 0eae6e7..c3f5b52 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,21 +1,674 @@
-MIT License
-
-Copyright (c) 2018 arnau
-
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+
+16. Limitation of Liability.
+
+IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+17. Interpretation of Sections 15 and 16.
+
+If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+ END OF TERMS AND CONDITIONS
+
+How to Apply These Terms to Your New Programs
+
+If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+To do so, attach the following notices to the program. It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+
+Copyright (C)
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see .
+
+Also add information on how to contact you by electronic and paper mail.
+
+If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+ Copyright (C)
+This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+This is free software, and you are welcome to redistribute it
+under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License. Of course, your program's commands
+might be different; for a GUI interface, you would use an "about box".
+
+You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU GPL, see
+.
+
+The GNU General Public License does not permit incorporating your program
+into proprietary programs. If your program is a subroutine library, you
+may consider it more useful to permit linking proprietary applications with
+the library. If this is what you want to do, use the GNU Lesser General
+Public License instead of this License. But first, please read
+.
diff --git a/README.md b/README.md
index b49be32..a85ce63 100644
--- a/README.md
+++ b/README.md
@@ -186,15 +186,15 @@ if err!=nil {
fmt.Println(err)
}
-// define how many secrets are needed to recover the secret
-nNeededSecrets := big.NewInt(int64(3))
-
// define how many shares want to generate
nShares := big.NewInt(int64(6))
+// define how many shares are needed to recover the secret
+nNeededShares := big.NewInt(int64(3))
+
// create the shares
shares, err := Create(
- nNeededSecrets,
+ nNeededShares,
nShares,
p,
big.NewInt(int64(k)))
diff --git a/bn128/README.md b/bn128/README.md
new file mode 100644
index 0000000..ff43b3e
--- /dev/null
+++ b/bn128/README.md
@@ -0,0 +1,145 @@
+## Bn128
+**[not finished]**
+
+This is implemented followng the implementations and info from:
+- https://github.com/zcash/zcash/tree/master/src/snark
+- https://github.com/iden3/snarkjs
+- https://github.com/ethereum/py_ecc/tree/master/py_ecc/bn128
+- `Multiplication and Squaring on Pairing-Friendly
+Fields`, Augusto Jun Devegili, Colm Ó hÉigeartaigh, Michael Scott, and Ricardo Dahab https://pdfs.semanticscholar.org/3e01/de88d7428076b2547b60072088507d881bf1.pdf
+- `Optimal Pairings`, Frederik Vercauteren https://www.cosic.esat.kuleuven.be/bcrypt/optimal.pdf
+- `Double-and-Add with Relative Jacobian
+Coordinates`, Björn Fay https://eprint.iacr.org/2014/1014.pdf
+- `Fast and Regular Algorithms for Scalar Multiplication
+over Elliptic Curves`, Matthieu Rivain https://eprint.iacr.org/2011/338.pdf
+
+- [x] Fq, Fq2, Fq6, Fq12 operations
+- [x] G1, G2 operations
+
+
+#### Usage
+First let's define three basic functions to convert integer compositions to big integer compositions:
+```go
+func iToBig(a int) *big.Int {
+ return big.NewInt(int64(a))
+}
+
+func iiToBig(a, b int) [2]*big.Int {
+ return [2]*big.Int{iToBig(a), iToBig(b)}
+}
+
+func iiiToBig(a, b int) [2]*big.Int {
+ return [2]*big.Int{iToBig(a), iToBig(b)}
+}
+```
+
+- Finite Fields (1, 2, 6, 12) operations
+```go
+// new finite field of order 1
+fq1 := NewFq(iToBig(7))
+
+// basic operations of finite field 1
+res := fq1.Add(iToBig(4), iToBig(4))
+res = fq1.Double(iToBig(5))
+res = fq1.Sub(iToBig(5), iToBig(7))
+res = fq1.Neg(iToBig(5))
+res = fq1.Mul(iToBig(5), iToBig(11))
+res = fq1.Inverse(iToBig(4))
+res = fq1.Square(iToBig(5))
+
+// new finite field of order 2
+nonResidueFq2str := "-1" // i / Beta
+nonResidueFq2, ok := new(big.Int).SetString(nonResidueFq2str, 10)
+fq2 := Fq2{fq1, nonResidueFq2}
+nonResidueFq6 := iiToBig(9, 1)
+
+// basic operations of finite field of order 2
+res := fq2.Add(iiToBig(4, 4), iiToBig(3, 4))
+res = fq2.Double(iiToBig(5, 3))
+res = fq2.Sub(iiToBig(5, 3), iiToBig(7, 2))
+res = fq2.Neg(iiToBig(4, 4))
+res = fq2.Mul(iiToBig(4, 4), iiToBig(3, 4))
+res = fq2.Inverse(iiToBig(4, 4))
+res = fq2.Div(iiToBig(4, 4), iiToBig(3, 4))
+res = fq2.Square(iiToBig(4, 4))
+
+
+// new finite field of order 6
+nonResidueFq6 := iiToBig(9, 1) // TODO
+fq6 := Fq6{fq2, nonResidueFq6}
+
+// define two new values of Finite Field 6, in order to be able to perform the operations
+a := [3][2]*big.Int{
+ iiToBig(1, 2),
+ iiToBig(3, 4),
+ iiToBig(5, 6)}
+b := [3][2]*big.Int{
+ iiToBig(12, 11),
+ iiToBig(10, 9),
+ iiToBig(8, 7)}
+
+// basic operations of finite field order 6
+res := fq6.Add(a, b)
+res = fq6.Sub(a, b)
+res = fq6.Mul(a, b)
+divRes := fq6.Div(mulRes, b)
+
+
+// new finite field of order 12
+q, ok := new(big.Int).SetString("21888242871839275222246405745257275088696311157297823662689037894645226208583", 10) // i
+if !ok {
+ fmt.Println("error parsing string to big integer")
+}
+
+fq1 := NewFq(q)
+nonResidueFq2, ok := new(big.Int).SetString("21888242871839275222246405745257275088696311157297823662689037894645226208582", 10) // i
+assert.True(t, ok)
+nonResidueFq6 := iiToBig(9, 1)
+
+fq2 := Fq2{fq1, nonResidueFq2}
+fq6 := Fq6{fq2, nonResidueFq6}
+fq12 := Fq12{fq6, fq2, nonResidueFq6}
+
+```
+
+- G1 operations
+```go
+bn128, err := NewBn128()
+assert.Nil(t, err)
+
+r1 := big.NewInt(int64(33))
+r2 := big.NewInt(int64(44))
+
+gr1 := bn128.G1.MulScalar(bn128.G1.G, bn128.Fq1.Copy(r1))
+gr2 := bn128.G1.MulScalar(bn128.G1.G, bn128.Fq1.Copy(r2))
+
+grsum1 := bn128.G1.Add(gr1, gr2)
+r1r2 := bn128.Fq1.Add(r1, r2)
+grsum2 := bn128.G1.MulScalar(bn128.G1.G, r1r2)
+
+a := bn128.G1.Affine(grsum1)
+b := bn128.G1.Affine(grsum2)
+assert.Equal(t, a, b)
+assert.Equal(t, "0x2f978c0ab89ebaa576866706b14787f360c4d6c3869efe5a72f7c3651a72ff00", utils.BytesToHex(a[0].Bytes()))
+assert.Equal(t, "0x12e4ba7f0edca8b4fa668fe153aebd908d322dc26ad964d4cd314795844b62b2", utils.BytesToHex(a[1].Bytes()))
+```
+
+- G2 operations
+```go
+bn128, err := NewBn128()
+assert.Nil(t, err)
+
+r1 := big.NewInt(int64(33))
+r2 := big.NewInt(int64(44))
+
+gr1 := bn128.G2.MulScalar(bn128.G2.G, bn128.Fq1.Copy(r1))
+gr2 := bn128.G2.MulScalar(bn128.G2.G, bn128.Fq1.Copy(r2))
+
+grsum1 := bn128.G2.Add(gr1, gr2)
+r1r2 := bn128.Fq1.Add(r1, r2)
+grsum2 := bn128.G2.MulScalar(bn128.G2.G, r1r2)
+
+a := bn128.G2.Affine(grsum1)
+b := bn128.G2.Affine(grsum2)
+assert.Equal(t, a, b)
+```
diff --git a/bn128/fq.go b/bn128/fq.go
index 615122e..9021802 100644
--- a/bn128/fq.go
+++ b/bn128/fq.go
@@ -89,3 +89,6 @@ func (fq Fq) Copy(a *big.Int) *big.Int {
func (fq Fq) Affine(a *big.Int) *big.Int {
return a
}
+func (fq Fq) Equal(a, b *big.Int) bool {
+ return bytes.Equal(a.Bytes(), b.Bytes())
+}
diff --git a/bn128/fq2.go b/bn128/fq2.go
index 401bab5..db1fe82 100644
--- a/bn128/fq2.go
+++ b/bn128/fq2.go
@@ -135,3 +135,6 @@ func (fq2 Fq2) Affine(a [2]*big.Int) [2]*big.Int {
fq2.F.Affine(a[1]),
}
}
+func (fq2 Fq2) Equal(a, b [2]*big.Int) bool {
+ return fq2.F.Equal(a[0], b[0]) && fq2.F.Equal(a[1], b[1])
+}
diff --git a/bn128/g2.go b/bn128/g2.go
index 614fe72..ebb33b8 100644
--- a/bn128/g2.go
+++ b/bn128/g2.go
@@ -21,8 +21,8 @@ func NewG2(f Fq2, g [2][2]*big.Int) G2 {
return g2
}
-func (g2 G2) Zero() [2][2]*big.Int {
- return [2][2]*big.Int{g2.F.Zero(), g2.F.Zero()}
+func (g2 G2) Zero() [3][2]*big.Int {
+ return [3][2]*big.Int{g2.F.Zero(), g2.F.One(), g2.F.Zero()}
}
func (g2 G2) IsZero(p [3][2]*big.Int) bool {
return g2.F.IsZero(p[2])
@@ -155,7 +155,7 @@ func (g2 G2) MulScalar(base [3][2]*big.Int, e *big.Int) [3][2]*big.Int {
return res
}
-func (g2 G2) Affine(p [3][2]*big.Int) [2][2]*big.Int {
+func (g2 G2) Affine(p [3][2]*big.Int) [3][2]*big.Int {
if g2.IsZero(p) {
return g2.Zero()
}
@@ -167,8 +167,12 @@ func (g2 G2) Affine(p [3][2]*big.Int) [2][2]*big.Int {
zinv3 := g2.F.Mul(zinv2, zinv)
y := g2.F.Mul(p[1], zinv3)
- return [2][2]*big.Int{
+ return [3][2]*big.Int{
x,
y,
+ [2]*big.Int{
+ big.NewInt(int64(0)),
+ big.NewInt(int64(0)),
+ },
}
}
diff --git a/ecdsa/README.md b/ecdsa/README.md
new file mode 100644
index 0000000..70c8014
--- /dev/null
+++ b/ecdsa/README.md
@@ -0,0 +1,49 @@
+## ECC ECDSA
+- https://en.wikipedia.org/wiki/Elliptic_Curve_Digital_Signature_Algorithm
+
+- [x] define ECDSA data structure
+- [x] ECDSA Sign
+- [x] ECDSA Verify signature
+
+
+#### Usage
+```go
+// define new elliptic curve
+ec := ecc.NewEC(big.NewInt(int64(1)), big.NewInt(int64(18)), big.NewInt(int64(19)))
+// define new point
+g := ecc.Point{big.NewInt(int64(7)), big.NewInt(int64(11))}
+
+// define new ECDSA system
+dsa, err := NewDSA(ec, g)
+if err!=nil {
+ fmt.Println(err)
+}
+
+// define privK&pubK over the elliptic curve
+privK := big.NewInt(int64(5))
+pubK, err := dsa.PubK(privK)
+if err!=nil {
+ fmt.Println(err)
+}
+
+// hash value to sign
+hashval := big.NewInt(int64(40))
+
+// define r
+r := big.NewInt(int64(11))
+
+// sign hashed value
+sig, err := dsa.Sign(hashval, privK, r)
+if err!=nil {
+ fmt.Println(err)
+}
+
+// verify signature
+verified, err := dsa.Verify(hashval, sig, pubK)
+if err!=nil {
+ fmt.Println(err)
+}
+if verified {
+ fmt.Println("signature correctly verified")
+}
+```
diff --git a/elgamal/README.md b/elgamal/README.md
new file mode 100644
index 0000000..e164f36
--- /dev/null
+++ b/elgamal/README.md
@@ -0,0 +1,50 @@
+## ECC ElGamal
+- https://en.wikipedia.org/wiki/ElGamal_encryption
+
+- [x] ECC ElGamal key generation
+- [x] ECC ElGamal Encrypton
+- [x] ECC ElGamal Decryption
+
+
+#### Usage
+- NewEG, Encryption, Decryption
+```go
+// define new elliptic curve
+ec := ecc.NewEC(big.NewInt(int64(1)), big.NewInt(int64(18)), big.NewInt(int64(19)))
+
+// define new point
+g := ecc.Point{big.NewInt(int64(7)), big.NewInt(int64(11))}
+
+// define new ElGamal crypto system with the elliptic curve and the point
+eg, err := NewEG(ec, g)
+if err!=nil {
+ fmt.Println(err)
+}
+
+// define privK&pubK over the elliptic curve
+privK := big.NewInt(int64(5))
+pubK, err := eg.PubK(privK)
+if err!=nil {
+ fmt.Println(err)
+}
+
+// define point to encrypt
+m := ecc.Point{big.NewInt(int64(11)), big.NewInt(int64(12))}
+
+// encrypt
+c, err := eg.Encrypt(m, pubK, big.NewInt(int64(15)))
+if err!=nil {
+ fmt.Println(err)
+}
+
+// decrypt
+d, err := eg.Decrypt(c, privK)
+if err!=nil {
+ fmt.Println(err)
+}
+
+// check that decryption is correct
+if !m.Equal(d) {
+ fmt.Println("decrypted not equal to original")
+}
+```
diff --git a/paillier/README.md b/paillier/README.md
new file mode 100644
index 0000000..0b206f7
--- /dev/null
+++ b/paillier/README.md
@@ -0,0 +1,56 @@
+## Paillier cryptosystem & Homomorphic Addition
+- https://en.wikipedia.org/wiki/Paillier_cryptosystem
+- https://en.wikipedia.org/wiki/Homomorphic_encryption
+
+- [x] GenerateKeyPair
+- [x] Encrypt
+- [x] Decrypt
+- [x] Homomorphic Addition
+
+#### Usage
+- Encrypt, Decrypt
+```go
+// key generation
+key, err := GenerateKeyPair()
+if err!=nil {
+ fmt.Println(err)
+}
+
+mBytes := []byte("Hi")
+m := new(big.Int).SetBytes(mBytes)
+
+// encryption
+c := Encrypt(m, key.PubK)
+
+// decryption
+d := Decrypt(c, key.PubK, key.PrivK)
+if m == d {
+ fmt.Println("ciphertext decrypted correctly")
+}
+```
+
+- Homomorphic Addition
+```go
+// key generation [Alice]
+key, err := GenerateKeyPair()
+if err!=nil {
+ fmt.Println(err)
+}
+
+// define values [Alice]
+n1 := big.NewInt(int64(110))
+n2 := big.NewInt(int64(150))
+
+// encrypt values [Alice]
+c1 := Encrypt(n1, key.PubK)
+c2 := Encrypt(n2, key.PubK)
+
+// compute homomorphic addition [Bob]
+c3c4 := HomomorphicAddition(c1, c2, key.PubK)
+
+// decrypt the result [Alice]
+d := Decrypt(c3c4, key.PubK, key.PrivK)
+if !bytes.Equal(new(big.Int).Add(n1, n2).Bytes(), d.Bytes()) {
+ fmt.Println("decrypted result not equal to expected result")
+}
+```
diff --git a/rsa/README.md b/rsa/README.md
new file mode 100644
index 0000000..a5ba489
--- /dev/null
+++ b/rsa/README.md
@@ -0,0 +1,94 @@
+## RSA cryptosystem & Blind signature & Homomorphic Multiplication
+- https://en.wikipedia.org/wiki/RSA_(cryptosystem)#
+- https://en.wikipedia.org/wiki/Blind_signature
+- https://en.wikipedia.org/wiki/Homomorphic_encryption
+
+- [x] GenerateKeyPair
+- [x] Encrypt
+- [x] Decrypt
+- [x] Blind
+- [x] Blind Signature
+- [x] Unblind Signature
+- [x] Verify Signature
+- [x] Homomorphic Multiplication
+
+
+#### Usage
+- Key generation, Encryption, Decryption
+```go
+// generate key pair
+key, err := GenerateKeyPair()
+if err!=nil {
+ fmt.Println(err)
+}
+mBytes := []byte("Hi")
+m := new(big.Int).SetBytes(mBytes)
+
+// encrypt message
+c := Encrypt(m, key.PubK)
+
+// decrypt ciphertext
+d := Decrypt(c, key.PrivK)
+if m == d {
+ fmt.Println("correctly decrypted")
+}
+```
+
+- Blind signatures
+```go
+// key generation [Alice]
+key, err := GenerateKeyPair()
+if err!=nil {
+ fmt.Println(err)
+}
+
+// create new message [Alice]
+mBytes := []byte("Hi")
+m := new(big.Int).SetBytes(mBytes)
+
+// define r value [Alice]
+rVal := big.NewInt(int64(101))
+
+// blind message [Alice]
+mBlinded := Blind(m, rVal, key.PubK)
+
+// Blind Sign the blinded message [Bob]
+sigma := BlindSign(mBlinded, key.PrivK)
+
+// unblind the blinded signed message, and get the signature of the message [Alice]
+mSigned := Unblind(sigma, rVal, key.PubK)
+
+// verify the signature [Alice/Bob/Trudy]
+verified := Verify(m, mSigned, key.PubK)
+if !verified {
+ fmt.Println("signature could not be verified")
+}
+```
+
+- Homomorphic Multiplication
+```go
+// key generation [Alice]
+key, err := GenerateKeyPair()
+if err!=nil {
+ fmt.Println(err)
+}
+
+// define values [Alice]
+n1 := big.NewInt(int64(11))
+n2 := big.NewInt(int64(15))
+
+// encrypt the values [Alice]
+c1 := Encrypt(n1, key.PubK)
+c2 := Encrypt(n2, key.PubK)
+
+// compute homomorphic multiplication with the encrypted values [Bob]
+c3c4 := HomomorphicMul(c1, c2, key.PubK)
+
+// decrypt the result [Alice]
+d := Decrypt(c3c4, key.PrivK)
+
+// check that the result is the expected
+if !bytes.Equal(new(big.Int).Mul(n1, n2).Bytes(), d.Bytes()) {
+ fmt.Println("decrypted result not equal to expected result")
+}
+```
diff --git a/schnorr/README.md b/schnorr/README.md
new file mode 100644
index 0000000..5f57e38
--- /dev/null
+++ b/schnorr/README.md
@@ -0,0 +1,47 @@
+## Schnorr signature
+- https://en.wikipedia.org/wiki/Schnorr_signature
+
+- [x] Hash[M || R] (where M is the msg bytes and R is a Point on the ECC, using sha256 hash function)
+- [x] Generate Schnorr scheme
+- [x] Sign
+- [x] Verify signature
+
+
+#### Usage
+```go
+// define new elliptic curve
+ec := ecc.NewEC(big.NewInt(int64(0)), big.NewInt(int64(7)), big.NewInt(int64(11)))
+// define new point
+g := ecc.Point{big.NewInt(int64(11)), big.NewInt(int64(27))} // Generator
+// define new random r
+r := big.NewInt(int64(23)) // random r
+
+// define new Schnorr crypto system using the values
+schnorr, sk, err := Gen(ec, g, r)
+if err!=nil {
+ fmt.println(err)
+}
+
+// define message to sign
+m := []byte("hola")
+
+// also we can hash the message, but it's not mandatory, as it will be done inside the schnorr.Sign, but we can perform it now, just to check the function
+h := Hash([]byte("hola"), c)
+if h.String() != "34719153732582497359642109898768696927847420320548121616059449972754491425079") {
+ fmt.Println("not correctly hashed")
+}
+
+s, rPoint, err := schnorr.Sign(sk, m)
+if err!=nil {
+ fmt.println(err)
+}
+
+// verify Schnorr signature
+verified, err := Verify(schnorr.EC, sk.PubK, m, s, rPoint)
+if err!=nil {
+ fmt.println(err)
+}
+if verified {
+ fmt.Println("Schnorr signature correctly verified")
+}
+```
diff --git a/schnorr/schnorr.go b/schnorr/schnorr.go
index 184f528..75f261e 100644
--- a/schnorr/schnorr.go
+++ b/schnorr/schnorr.go
@@ -130,6 +130,9 @@ func Verify(ec ecc.EC, pk PubK, m []byte, s *big.Int, rPoint ecc.Point) (bool, e
// s x P
sp, err := ec.Mul(pk.P, s)
+ if err != nil {
+ return false, err
+ }
// return reQ.Equal(sp), nil
return eQ.Equal(sp), nil
diff --git a/shamirsecretsharing/README.md b/shamirsecretsharing/README.md
new file mode 100644
index 0000000..ff411d8
--- /dev/null
+++ b/shamirsecretsharing/README.md
@@ -0,0 +1,48 @@
+## Shamir Secret Sharing
+- https://en.wikipedia.org/wiki/Shamir%27s_Secret_Sharing
+
+- [x] create secret sharing from number of secrets needed, number of shares, random point p, secret to share
+- [x] Lagrange Interpolation to restore the secret from the shares
+
+#### Usage
+```go
+// define secret to share
+k := 123456789
+
+// define random prime
+p, err := rand.Prime(rand.Reader, bits/2)
+if err!=nil {
+ fmt.Println(err)
+}
+
+// define how many shares want to generate
+nShares := big.NewInt(int64(6))
+
+// define how many shares are needed to recover the secret
+nNeededShares := big.NewInt(int64(3))
+
+// create the shares
+shares, err := Create(
+ nNeededShares,
+ nShares,
+ p,
+ big.NewInt(int64(k)))
+assert.Nil(t, err)
+if err!=nil {
+ fmt.Println(err)
+}
+
+// select shares to use
+var sharesToUse [][]*big.Int
+sharesToUse = append(sharesToUse, shares[2])
+sharesToUse = append(sharesToUse, shares[1])
+sharesToUse = append(sharesToUse, shares[0])
+
+// recover the secret using Lagrange Interpolation
+secr := LagrangeInterpolation(sharesToUse, p)
+
+// check that the restored secret matches the original secret
+if !bytes.Equal(k.Bytes(), secr.Bytes()) {
+ fmt.Println("reconstructed secret not correspond to original secret")
+}
+```
diff --git a/shamirsecretsharing/shamirsecretsharing_test.go b/shamirsecretsharing/shamirsecretsharing_test.go
index b1048c5..f326ecc 100644
--- a/shamirsecretsharing/shamirsecretsharing_test.go
+++ b/shamirsecretsharing/shamirsecretsharing_test.go
@@ -15,10 +15,10 @@ func TestCreate(t *testing.T) {
p, err := rand.Prime(rand.Reader, bits/2)
assert.Nil(t, err)
- nNeededSecrets := big.NewInt(int64(3))
nShares := big.NewInt(int64(6))
+ nNeededShares := big.NewInt(int64(3))
shares, err := Create(
- nNeededSecrets,
+ nNeededShares,
nShares,
p,
k)