Sign CertificateVerify messages on a background thread.

net/ssl/threaded_ssl_private_key.h

+// Copyright 2015 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 NET_SSL_THREADED_SSL_PRIVATE_KEY_H_
+#define NET_SSL_THREADED_SSL_PRIVATE_KEY_H_
+
+#include <stdint.h>
+
+#include <vector>
+
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/weak_ptr.h"
+#include "base/strings/string_piece.h"
+#include "net/ssl/ssl_private_key.h"
+
+namespace base {
+class TaskRunner;
+}
+
+namespace net {
+
+// An SSLPrivateKey implementation which offloads key operations to a background
+// task runner.
+class ThreadedSSLPrivateKey : public SSLPrivateKey {
+ public:
+  // Interface for consumers to implement to perform the actual signing
+  // operation.
+  class Delegate {
+   public:
+    Delegate() {}
+    virtual ~Delegate() {}
+
+    // These methods behave as those of the same name on SSLPrivateKey. They
+    // must be callable on any thread.
+    virtual Type GetType() = 0;
+    virtual bool SupportsHash(Hash hash) = 0;
+    virtual size_t GetMaxSignatureLengthInBytes() = 0;
+
+    // Signs |input| as a digest of type |hash|. On sucess it returns OK and
+    // sets |signature| to the resulting signature. Otherwise it returns a net
+    // error code. It will only be called on the task runner passed to the
+    // owning ThreadedSSLPrivateKey.
+    virtual Error SignDigest(Hash hash,
+                             const base::StringPiece& input,
+                             std::vector<uint8_t>* signature) = 0;
+
+   private:
+    DISALLOW_COPY_AND_ASSIGN(Delegate);
+  };
+
+  ThreadedSSLPrivateKey(scoped_ptr<Delegate> delegate,
+                        scoped_refptr<base::TaskRunner> task_runner);
+  ~ThreadedSSLPrivateKey() override;
+
+  // SSLPrivateKey implementation.
+  Type GetType() override;
+  bool SupportsHash(Hash hash) override;
+  size_t GetMaxSignatureLengthInBytes() override;
+  void SignDigest(Hash hash,
+                  const base::StringPiece& input,
+                  const SignCallback& callback) override;
+
+ private:
+  class Core;
+
+  scoped_refptr<Core> core_;
+  scoped_refptr<base::TaskRunner> task_runner_;
+  base::WeakPtrFactory<ThreadedSSLPrivateKey> weak_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(ThreadedSSLPrivateKey);
+};
+
+}  // namespace net
+
+#endif  // NET_SSL_THREADED_SSL_PRIVATE_KEY_H_