// IsOnCurve, all other behavior is undefined.
func TestInvalidCoordinates(t *testing.T) {
	t.Parallel()
	testAllCurves(t, testInvalidCoordinates)
}

func testInvalidCoordinates(t *testing.T, curve Curve) {
	checkIsOnCurveFalse := func(name string, x, y *big.Int) {
		if curve.IsOnCurve(x, y) {
			t.Errorf("IsOnCurve(%s) unexpectedly returned true", name)
		}
	}

	p224 := P224()
	pointData, _ := hex.DecodeString("049B535B45FB0A2072398A6831834624C7E32CCFD5A4B933BCEAF77F1DD945E08BBE5178F5EDF5E733388F196D2A631D2E075BB16CBFEEA15B")
	x, y := Unmarshal(p224, pointData)
	if !p224.IsOnCurve(x, y) {
		t.Error("P224 failed to validate a correct point")
	}

pkg crypto/elliptic, method (*CurveParams) IsOnCurve //deprecated #34648
pkg crypto/elliptic, method (*CurveParams) ScalarBaseMult //deprecated #34648
pkg crypto/elliptic, method (*CurveParams) ScalarMult //deprecated #34648
pkg crypto/elliptic, type Curve interface, Add //deprecated #52221
pkg crypto/elliptic, type Curve interface, Double //deprecated #52221
pkg crypto/elliptic, type Curve interface, IsOnCurve //deprecated #52221

	testAllCurves(t, testKeyGeneration)
}

func testKeyGeneration(t *testing.T, c elliptic.Curve) {
	priv, err := GenerateKey(c, rand.Reader)
	if err != nil {
		t.Fatal(err)
	}
	if !c.IsOnCurve(priv.PublicKey.X, priv.PublicKey.Y) {
		t.Errorf("public key invalid: %s", err)
	}
}

func TestSignAndVerify(t *testing.T) {
	testAllCurves(t, testSignAndVerify)
}

// Curve is not supported by crypto/ecdh.
func (k *PublicKey) ECDH() (*ecdh.PublicKey, error) {
	c := curveToECDH(k.Curve)
	if c == nil {
		return nil, errors.New("ecdsa: unsupported curve by crypto/ecdh")
	}
	if !k.Curve.IsOnCurve(k.X, k.Y) {
		return nil, errors.New("ecdsa: invalid public key")
	}
	return c.NewPublicKey(elliptic.Marshal(k.Curve, k.X, k.Y))
}

// Equal reports whether pub and x have the same value.
//