first commit

libraries/vendor/web-token/jwt-signature-algorithm-hmac/HMAC.php

@@ -0,0 +1,49 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Jose\Component\Signature\Algorithm;
+
+use function in_array;
+use InvalidArgumentException;
+use function is_string;
+use Jose\Component\Core\JWK;
+use ParagonIE\ConstantTime\Base64UrlSafe;
+
+abstract class HMAC implements MacAlgorithm
+{
+    public function allowedKeyTypes(): array
+    {
+        return ['oct'];
+    }
+
+    public function verify(JWK $key, string $input, string $signature): bool
+    {
+        return hash_equals($this->hash($key, $input), $signature);
+    }
+
+    public function hash(JWK $key, string $input): string
+    {
+        $k = $this->getKey($key);
+
+        return hash_hmac($this->getHashAlgorithm(), $input, $k, true);
+    }
+
+    protected function getKey(JWK $key): string
+    {
+        if (! in_array($key->get('kty'), $this->allowedKeyTypes(), true)) {
+            throw new InvalidArgumentException('Wrong key type.');
+        }
+        if (! $key->has('k')) {
+            throw new InvalidArgumentException('The key parameter "k" is missing.');
+        }
+        $k = $key->get('k');
+        if (! is_string($k)) {
+            throw new InvalidArgumentException('The key parameter "k" is invalid.');
+        }
+
+        return Base64UrlSafe::decode($k);
+    }
+
+    abstract protected function getHashAlgorithm(): string;
+}