spaces.php

aws/Aws/S3/SSECMiddleware.php

@@ -0,0 +1,75 @@
+<?php
+namespace Aws\S3;
+
+use Aws\CommandInterface;
+use Psr\Http\Message\RequestInterface;
+
+/**
+ * Simplifies the SSE-C process by encoding and hashing the key.
+ * @internal
+ */
+class SSECMiddleware
+{
+    private $endpointScheme;
+    private $nextHandler;
+
+    /**
+     * Provide the URI scheme of the client sending requests.
+     *
+     * @param string $endpointScheme URI scheme (http/https).
+     *
+     * @return callable
+     */
+    public static function wrap($endpointScheme)
+    {
+        return function (callable $handler) use ($endpointScheme) {
+            return new self($endpointScheme, $handler);
+        };
+    }
+
+    public function __construct($endpointScheme, callable $nextHandler)
+    {
+        $this->nextHandler = $nextHandler;
+        $this->endpointScheme = $endpointScheme;
+    }
+
+    public function __invoke(
+        CommandInterface $command,
+        RequestInterface $request = null
+    ) {
+        // Allows only HTTPS connections when using SSE-C
+        if (($command['SSECustomerKey'] || $command['CopySourceSSECustomerKey'])
+            && $this->endpointScheme !== 'https'
+        ) {
+            throw new \RuntimeException('You must configure your S3 client to '
+                . 'use HTTPS in order to use the SSE-C features.');
+        }
+
+        // Prepare the normal SSE-CPK headers
+        if ($command['SSECustomerKey']) {
+            $this->prepareSseParams($command);
+        }
+
+        // If it's a copy operation, prepare the SSE-CPK headers for the source.
+        if ($command['CopySourceSSECustomerKey']) {
+            $this->prepareSseParams($command, 'CopySource');
+        }
+
+        $f = $this->nextHandler;
+        return $f($command, $request);
+    }
+
+    private function prepareSseParams(CommandInterface $command, $prefix = '')
+    {
+        // Base64 encode the provided key
+        $key = $command[$prefix . 'SSECustomerKey'];
+        $command[$prefix . 'SSECustomerKey'] = base64_encode($key);
+
+        // Base64 the provided MD5 or, generate an MD5 if not provided
+        if ($md5 = $command[$prefix . 'SSECustomerKeyMD5']) {
+            $command[$prefix . 'SSECustomerKeyMD5'] = base64_encode($md5);
+        } else {
+            $command[$prefix . 'SSECustomerKeyMD5'] = base64_encode(md5($key, true));
+        }
+    }
+}