skip if curve not supported

Author: qmuntal

ec.go

@@ -5,10 +5,31 @@ package openssl
 import (
 	"errors"
 	"strconv"
+	"sync"
 
 	"github.com/golang-fips/openssl/v2/internal/ossl"
 )
 
+func SupportsCurve(curve string) bool {
+	switch curve {
+	case "P-224", "P-256", "P-384", "P-521":
+		return true
+	case "X25519":
+		return supportsX25519()
+	default:
+		return false
+	}
+}
+
+var supportsX25519 = sync.OnceValue(func() bool {
+	ctx, _ := ossl.EVP_PKEY_CTX_new_id(ossl.EVP_PKEY_X25519, nil)
+	if ctx != nil {
+		ossl.EVP_PKEY_CTX_free(ctx)
+		return true
+	}
+	return false
+})
+
 func curveID(curve string) int32 {
 	switch curve {
 	case "P-224":

ecdh_test.go

@@ -14,6 +14,7 @@ func TestECDH(t *testing.T) {
 	for _, tt := range []string{"P-256", "P-384", "P-521", "X25519"} {
 		t.Run(tt, func(t *testing.T) {
 			name := tt
+			skipUnsupportedCurve(t, name)
 			aliceKey, alicPrivBytes, err := openssl.GenerateKeyECDH(name)
 			if err != nil {
 				t.Fatal(err)
@@ -121,6 +122,7 @@ var ecdhvectors = []struct {
 func TestECDHVectors(t *testing.T) {
 	for _, tt := range ecdhvectors {
 		t.Run(tt.Name, func(t *testing.T) {
+			skipUnsupportedCurve(t, tt.Name)
 			key, err := openssl.NewPrivateKeyECDH(tt.Name, hexDecode(t, tt.PrivateKey))
 			if err != nil {
 				t.Fatal(err)
@@ -285,6 +287,7 @@ var invalidECDHPublicKeys = map[string][]string{
 func TestECDHNewPrivateKeyECDH_Invalid(t *testing.T) {
 	for _, curve := range []string{"P-256", "P-384", "P-521", "X25519"} {
 		t.Run(curve, func(t *testing.T) {
+			skipUnsupportedCurve(t, curve)
 			for _, input := range invalidECDHPrivateKeys[curve] {
 				k, err := openssl.NewPrivateKeyECDH(curve, hexDecode(t, input))
 				if err == nil {
@@ -300,6 +303,7 @@ func TestECDHNewPrivateKeyECDH_Invalid(t *testing.T) {
 func TestECDHNewPublicKeyECDH_Invalid(t *testing.T) {
 	for _, curve := range []string{"P-256", "P-384", "P-521", "X25519"} {
 		t.Run(curve, func(t *testing.T) {
+			skipUnsupportedCurve(t, curve)
 			for _, input := range invalidECDHPublicKeys[curve] {
 				k, err := openssl.NewPublicKeyECDH(curve, hexDecode(t, input))
 				if err == nil {
@@ -313,6 +317,7 @@ func TestECDHNewPublicKeyECDH_Invalid(t *testing.T) {
 }
 
 func TestX25519Failure(t *testing.T) {
+	skipUnsupportedCurve(t, "X25519")
 	identity := hexDecode(t, "0000000000000000000000000000000000000000000000000000000000000000")
 	lowOrderPoint := hexDecode(t, "e0eb7a7c3b41b8ae1656e3faf19fc46ada098deb9c32b1fd866205165f49b800")
 	randomScalar := make([]byte, 32)
@@ -340,3 +345,10 @@ func testX25519Failure(t *testing.T, private, public []byte) {
 		t.Errorf("unexpected ECDH output: %x", secret)
 	}
 }
+
+func skipUnsupportedCurve(t *testing.T, curve string) {
+	t.Helper()
+	if !openssl.SupportsCurve(curve) {
+		t.Skipf("skipping test: curve %q is not supported", curve)
+	}
+}