Fix ed25519 public key (#519)

Fix EdDSA algorithm

Author: Spomky

composer.json

@@ -101,6 +101,7 @@
         "ext-sodium": "*",
         "brick/math": "^0.9|^0.10|^0.11|^0.12",
         "paragonie/constant_time_encoding": "^2.6",
+        "paragonie/sodium_compat": "^1.20",
         "psr/clock": "^1.0",
         "psr/event-dispatcher": "^1.0",
         "psr/http-client": "^1.0",

src/Component/KeyManagement/KeyConverter/KeyConverter.php

@@ -7,6 +7,7 @@
 use InvalidArgumentException;
 use OpenSSLCertificate;
 use ParagonIE\ConstantTime\Base64UrlSafe;
+use ParagonIE\Sodium\Core\Ed25519;
 use RuntimeException;
 use SpomkyLabs\Pki\CryptoEncoding\PEM;
 use SpomkyLabs\Pki\CryptoTypes\Asymmetric\PrivateKey;
@@ -250,14 +251,29 @@ private static function tryToLoadOtherKeyTypes(string $input): array
      */
     private static function populatePoints(PrivateKey $key, array $values): array
     {
-        if (($values['crv'] === 'Ed25519' || $values['crv'] === 'X25519') && extension_loaded('sodium')) {
-            $x = sodium_crypto_scalarmult_base($key->privateKeyData());
+        $x = self::getPublicKey($key, $values['crv']);
+        if ($x !== null) {
             $values['x'] = Base64UrlSafe::encodeUnpadded($x);
         }
 
         return $values;
     }
 
+    private static function getPublicKey(PrivateKey $key, string $crv): ?string
+    {
+        switch ($crv) {
+            case 'Ed25519':
+                return Ed25519::publickey_from_secretkey($key->privateKeyData());
+            case 'X25519':
+                if (extension_loaded('sodium')) {
+                    return sodium_crypto_scalarmult_base($key->privateKeyData());
+                }
+                // no break
+            default:
+                return null;
+        }
+    }
+
     private static function checkType(string $curve): void
     {
         $curves = ['Ed448ph', 'Ed25519ph', 'Ed448', 'Ed25519', 'X448', 'X25519'];

src/SignatureAlgorithm/EdDSA/EdDSA.php

@@ -7,6 +7,7 @@
 use InvalidArgumentException;
 use Jose\Component\Core\JWK;
 use ParagonIE\ConstantTime\Base64UrlSafe;
+use ParagonIE\Sodium\Core\Ed25519;
 use RuntimeException;
 use function extension_loaded;
 use function in_array;
@@ -40,7 +41,7 @@ public function sign(JWK $key, string $input): string
             throw new InvalidArgumentException('Invalid "d" parameter.');
         }
         if (! $key->has('x')) {
-            $x = sodium_crypto_sign_publickey_from_secretkey($d);
+            $x = $this->getPublicKey($key);
         } else {
             $x = $key->get('x');
         }
@@ -84,6 +85,21 @@ public function name(): string
         return 'EdDSA';
     }
 
+    private static function getPublicKey(JWK $key): string
+    {
+        switch ($key->get('crv')) {
+            case 'Ed25519':
+                return Ed25519::publickey_from_secretkey($key->get('d'));
+            case 'X25519':
+                if (extension_loaded('sodium')) {
+                    return sodium_crypto_scalarmult_base($key->get('d'));
+                }
+                // no break
+            default:
+                throw new InvalidArgumentException('Unsupported key type');
+        }
+    }
+
     private function checkKey(JWK $key): void
     {
         if (! in_array($key->get('kty'), $this->allowedKeyTypes(), true)) {

src/SignatureAlgorithm/EdDSA/composer.json

@@ -40,6 +40,7 @@
     "require": {
         "php": ">=8.1",
         "ext-sodium": "*",
+        "paragonie/sodium_compat": "^1.20",
         "web-token/jwt-signature": "^3.2"
     }
 }

tests/Component/KeyManagement/JWKFactoryTest.php

@@ -297,7 +297,7 @@ public static function dataKeys(): iterable
                 'kty' => 'OKP',
                 'crv' => 'Ed25519',
                 'd' => 'Pr9AxZivB-zSq95wLrZfYa7DQ3TUPqZTkP_0w33r3rc',
-                'x' => 'uRhai1TsvrSB43HD-36TQ2hMQfV8ruJz7F8o0wIe1VI',
+                'x' => 'wrI33AEj15KHHYplueUE5cnJKtbM8oVHFf6wGnw2oOE',
             ],
         ];
         yield [