Refactor WebCrypto code

content/child/webcrypto/algorithm_registry.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef CONTENT_CHILD_WEBCRYPTO_JWK_H_
-#define CONTENT_CHILD_WEBCRYPTO_JWK_H_
+#ifndef CONTENT_CHILD_WEBCRYPTO_ALGORITHM_REGISTRY_H_
+#define CONTENT_CHILD_WEBCRYPTO_ALGORITHM_REGISTRY_H_
 
-#include <vector>
-
-#include "base/basictypes.h"
-#include "third_party/WebKit/public/platform/WebArrayBuffer.h"
 #include "third_party/WebKit/public/platform/WebCrypto.h"
-#include "third_party/WebKit/public/platform/WebCryptoAlgorithmParams.h"
 
 namespace content {
 
 namespace webcrypto {
 
-class CryptoData;
+class AlgorithmImplementation;
 class Status;
 
-Status ImportKeyJwk(const CryptoData& key_data,
-                    const blink::WebCryptoAlgorithm& algorithm,
-                    bool extractable,
-                    blink::WebCryptoKeyUsageMask usage_mask,
-                    blink::WebCryptoKey* key);
-
-Status ExportKeyJwk(const blink::WebCryptoKey& key, std::vector<uint8>* buffer);
+// Retrieves the AlgorithmImplementation applicable for |id|.
+//
+// If there is no available implementation, then an error is returned, and
+// *impl is set to NULL.
+//
+// Otherwise Success is returned and *impl is set to a non-NULL value. The
+// AlgorithmImplementation pointer will remain valid until the program's
+// termination.
+Status GetAlgorithmImplementation(blink::WebCryptoAlgorithmId id,
+                                  const AlgorithmImplementation** impl);

[Ryan Sleevi, 2014/07/12 00:55:27]

How is this model supposed to support IPC-based crypto in the future?

That is, you're (indirectly) continuing a Singleton, where before, there was a
little bit of distinction (via PlatformCrypto having the virtual methods)

I'm having trouble convincing myself this is an idea we'll grow with, and wonder
whether the implementations shouldn't hang off a context object that is passed
around.

[eroman, 2014/07/12 01:59:30]

This is no different than before. Previously the platform crypto layer was just
a set of global functions so this isn't weaking any IPC handling.

The layering right now goes like:

(1) blink --> (2) WebCryptoImpl --> (3) post to crypto thread --> (4)
algorithm_dispatch.cc --> (5) AlgorithmImplementation

Depending what we want to achieve with the browser side crypto, I could imagine
a desin where you modify step (2), so instead of posting to the crypto thread it
serializes the blink::WebCryptoAlgorithm and calls an async IPC. The browser
side would then unmarshal the algorithm and be ready to resume things at step
(2)

 
 }  // namespace webcrypto
 
 }  // namespace content
 
-#endif  // CONTENT_CHILD_WEBCRYPTO_JWK_H_
+#endif  // CONTENT_CHILD_WEBCRYPTO_ALGORITHM_REGISTRY_H_