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|
package secp256k1
import (
"bytes"
"encoding/hex"
"math/big"
"testing"
)
func TestTaggedHash(t *testing.T) {
// Just verify it produces 32 bytes
result := TaggedHash("test", []byte("hello"))
if len(result) != 32 {
t.Errorf("expected 32 bytes, got %d", len(result))
}
// Same inputs should produce same output
result2 := TaggedHash("test", []byte("hello"))
if !bytes.Equal(result, result2) {
t.Error("tagged hash should be deterministic")
}
// Different tag should produce different output
result3 := TaggedHash("other", []byte("hello"))
if bytes.Equal(result, result3) {
t.Error("different tags should produce different hashes")
}
}
func TestLiftX(t *testing.T) {
// Lift G.x should give us G (or its negation with even y)
p, err := liftX(Gx)
if err != nil {
t.Fatalf("failed to lift G.x: %v", err)
}
if !p.IsOnCurve() {
t.Error("lifted point should be on curve")
}
// x should match
if p.x.value.Cmp(Gx) != 0 {
t.Error("lifted x should match input")
}
// y should be even (BIP-340 convention)
if !hasEvenY(p) {
t.Error("lifted point should have even y")
}
}
func TestLiftXInvalid(t *testing.T) {
// x = 0 is not on the curve (0³ + 7 = 7, and 7 has no sqrt mod p)
_, err := liftX(big.NewInt(0))
if err == nil {
t.Error("x=0 should not be on curve")
}
}
func TestSignAndVerify(t *testing.T) {
priv, _ := GeneratePrivateKey()
pub := priv.PublicKey()
message := []byte("hello world")
sig, err := Sign(priv, message)
if err != nil {
t.Fatalf("signing failed: %v", err)
}
if !Verify(pub, message, sig) {
t.Error("signature should verify")
}
}
func TestSignatureIsDeteministic(t *testing.T) {
priv, _ := NewPrivateKeyFromHex("0000000000000000000000000000000000000000000000000000000000000001")
message := []byte("test message")
sig1, _ := Sign(priv, message)
sig2, _ := Sign(priv, message)
if sig1.R.Cmp(sig2.R) != 0 || sig1.S.Cmp(sig2.S) != 0 {
t.Error("BIP-340 signing should be deterministic")
}
}
func TestVerifyWrongMessage(t *testing.T) {
priv, _ := GeneratePrivateKey()
pub := priv.PublicKey()
sig, _ := Sign(priv, []byte("correct message"))
if Verify(pub, []byte("wrong message"), sig) {
t.Error("signature should not verify with wrong message")
}
}
func TestVerifyWrongPublicKey(t *testing.T) {
priv1, _ := GeneratePrivateKey()
priv2, _ := GeneratePrivateKey()
pub2 := priv2.PublicKey()
message := []byte("test")
sig, _ := Sign(priv1, message)
if Verify(pub2, message, sig) {
t.Error("signature should not verify with wrong public key")
}
}
func TestVerifyTamperedSignature(t *testing.T) {
priv, _ := GeneratePrivateKey()
pub := priv.PublicKey()
message := []byte("test")
sig, _ := Sign(priv, message)
// Tamper with s
tamperedSig := &Signature{
R: sig.R,
S: new(big.Int).Add(sig.S, big.NewInt(1)),
}
if Verify(pub, message, tamperedSig) {
t.Error("tampered signature should not verify")
}
}
func TestSignatureBytes(t *testing.T) {
priv, _ := GeneratePrivateKey()
message := []byte("test")
sig, _ := Sign(priv, message)
b := sig.Bytes()
if len(b) != 64 {
t.Errorf("signature should be 64 bytes, got %d", len(b))
}
}
func TestSignatureRoundTrip(t *testing.T) {
priv, _ := GeneratePrivateKey()
message := []byte("test")
sig1, _ := Sign(priv, message)
b := sig1.Bytes()
sig2, err := SignatureFromBytes(b)
if err != nil {
t.Fatalf("failed to parse signature: %v", err)
}
if sig1.R.Cmp(sig2.R) != 0 || sig1.S.Cmp(sig2.S) != 0 {
t.Error("signature should survive round-trip")
}
}
func TestSignatureFromBytesInvalid(t *testing.T) {
_, err := SignatureFromBytes(make([]byte, 63))
if err == nil {
t.Error("should reject wrong-length input")
}
}
// BIP-340 Test Vector 0
func TestBIP340Vector0(t *testing.T) {
privHex := "0000000000000000000000000000000000000000000000000000000000000003"
msgHex := "0000000000000000000000000000000000000000000000000000000000000000"
expectedSigHex := "e907831f80848d1069a5371b402410364bdf1c5f8307b0084c55f1ce2dca821525f66a4a85ea8b71e482a74f382d2ce5ebeee8fdb2172f477df4900d310536c0"
priv, err := NewPrivateKeyFromHex(privHex)
if err != nil {
t.Fatalf("failed to parse private key: %v", err)
}
msg, _ := hex.DecodeString(msgHex)
sig, err := Sign(priv, msg)
if err != nil {
t.Fatalf("signing failed: %v", err)
}
sigHex := sig.Hex()
if sigHex != expectedSigHex {
t.Errorf("signature mismatch\ngot: %s\nwant: %s", sigHex, expectedSigHex)
}
// Also verify it
pub := priv.PublicKey()
if !Verify(pub, msg, sig) {
t.Error("BIP-340 test vector should verify")
}
}
// BIP-340 Test Vector 1
func TestBIP340Vector1(t *testing.T) {
privHex := "b7e151628aed2a6abf7158809cf4f3c762e7160f38b4da56a784d9045190cfef"
msgHex := "243f6a8885a308d313198a2e03707344a4093822299f31d0082efa98ec4e6c89"
auxHex := "0000000000000000000000000000000000000000000000000000000000000001"
expectedSigHex := "6896bd60eeae296db48a229ff71dfe071bde413e6d43f917dc8dcf8c78de33418906d11ac976abccb20b091292bff4ea897efcb639ea871cfa95f6de339e4b0a"
priv, err := NewPrivateKeyFromHex(privHex)
if err != nil {
t.Fatalf("failed to parse private key: %v", err)
}
msg, _ := hex.DecodeString(msgHex)
aux, _ := hex.DecodeString(auxHex)
sig, err := Sign(priv, msg, aux)
if err != nil {
t.Fatalf("signing failed: %v", err)
}
sigHex := sig.Hex()
if sigHex != expectedSigHex {
t.Errorf("signature mismatch\ngot: %s\nwant: %s", sigHex, expectedSigHex)
}
pub := priv.PublicKey()
if !Verify(pub, msg, sig) {
t.Error("BIP-340 test vector should verify")
}
}
func TestXOnlyBytes(t *testing.T) {
priv, _ := NewPrivateKeyFromHex("0000000000000000000000000000000000000000000000000000000000000001")
pub := priv.PublicKey()
xOnly := pub.XOnlyBytes()
if len(xOnly) != 32 {
t.Errorf("x-only pubkey should be 32 bytes, got %d", len(xOnly))
}
// Should match G.x
expectedX := make([]byte, 32)
gxBytes := Gx.Bytes()
copy(expectedX[32-len(gxBytes):], gxBytes)
if !bytes.Equal(xOnly, expectedX) {
t.Error("x-only bytes should match G.x")
}
}
|
