spaces.php

aws/Aws/Crypto/AesGcmEncryptingStream.php

@@ -0,0 +1,101 @@
+<?php
+namespace Aws\Crypto;
+
+use GuzzleHttp\Psr7;
+use GuzzleHttp\Psr7\StreamDecoratorTrait;
+use Psr\Http\Message\StreamInterface;
+use \RuntimeException;
+
+/**
+ * @internal Represents a stream of data to be gcm encrypted.
+ */
+class AesGcmEncryptingStream implements AesStreamInterface
+{
+    use StreamDecoratorTrait;
+
+    private $aad;
+
+    private $initializationVector;
+
+    private $key;
+
+    private $keySize;
+
+    private $plaintext;
+
+    private $tag = '';
+
+    private $tagLength;
+
+    /**
+     * @param StreamInterface $plaintext
+     * @param string $key
+     * @param string $initializationVector
+     * @param string $aad
+     * @param int $tagLength
+     * @param int $keySize
+     */
+    public function __construct(
+        StreamInterface $plaintext,
+        $key,
+        $initializationVector,
+        $aad = '',
+        $tagLength = 16,
+        $keySize = 256
+    ) {
+        if (version_compare(PHP_VERSION, '7.1', '<')) {
+            throw new RuntimeException(
+                'AES-GCM decryption is only supported in PHP 7.1 or greater'
+            );
+        }
+
+        $this->plaintext = $plaintext;
+        $this->key = $key;
+        $this->initializationVector = $initializationVector;
+        $this->aad = $aad;
+        $this->tagLength = $tagLength;
+        $this->keySize = $keySize;
+    }
+
+    public function getOpenSslName()
+    {
+        return "aes-{$this->keySize}-gcm";
+    }
+
+    public function getAesName()
+    {
+        return 'AES/GCM/NoPadding';
+    }
+
+    public function getCurrentIv()
+    {
+        return $this->initializationVector;
+    }
+
+    public function createStream()
+    {
+        return Psr7\stream_for(openssl_encrypt(
+            (string) $this->plaintext,
+            $this->getOpenSslName(),
+            $this->key,
+            OPENSSL_RAW_DATA,
+            $this->initializationVector,
+            $this->tag,
+            $this->aad,
+            $this->tagLength
+        ));
+    }
+
+    /**
+     * @return string
+     */
+    public function getTag()
+    {
+        return $this->tag;
+    }
+
+    public function isWritable()
+    {
+        return false;
+    }
+}