Refactor WebCrypto code

content/child/webcrypto/nss/util_nss.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_NSS_UTIL_NSS_H_
+#define CONTENT_CHILD_WEBCRYPTO_NSS_UTIL_NSS_H_
+
+#include <keythi.h>
+#include <pkcs11t.h>
+#include <seccomon.h>
+#include <secmodt.h>
+
+#include "base/lazy_instance.h"
+
+namespace content {
+
+namespace webcrypto {
+
+class CryptoData;
+
+SECItem MakeSECItemForBuffer(const CryptoData& buffer);
+enum EncryptOrDecrypt { ENCRYPT, DECRYPT };
+
+CryptoData SECItemToCryptoData(const SECItem& item);
+
+// Signature for PK11_Encrypt and PK11_Decrypt.
+typedef SECStatus (*PK11_EncryptDecryptFunction)(PK11SymKey*,
+                                                 CK_MECHANISM_TYPE,
+                                                 SECItem*,
+                                                 unsigned char*,
+                                                 unsigned int*,
+                                                 unsigned int,
+                                                 const unsigned char*,
+                                                 unsigned int);
+
+// Signature for PK11_PubEncrypt
+typedef SECStatus (*PK11_PubEncryptFunction)(SECKEYPublicKey*,
+                                             CK_MECHANISM_TYPE,
+                                             SECItem*,
+                                             unsigned char*,
+                                             unsigned int*,
+                                             unsigned int,
+                                             const unsigned char*,
+                                             unsigned int,
+                                             void*);
+
+// Signature for PK11_PrivDecrypt
+typedef SECStatus (*PK11_PrivDecryptFunction)(SECKEYPrivateKey*,
+                                              CK_MECHANISM_TYPE,
+                                              SECItem*,
+                                              unsigned char*,
+                                              unsigned int*,
+                                              unsigned int,
+                                              const unsigned char*,
+                                              unsigned int);
+
+// Singleton that detects whether or not AES-GCM and
+// RSA-OAEP are supported by the version of NSS being used.
+// On non-Linux platforms, Chromium embedders ship with a
+// fixed version of NSS, and these are always available.
+// However, on Linux (and ChromeOS), NSS is provided by the
+// system, and thus not all algorithms may be available
+// or be safe to use.
+class NssRuntimeSupport {
+ public:
+  bool IsAesGcmSupported() const {
+    return pk11_encrypt_func_ && pk11_decrypt_func_;
+  }
+
+  bool IsRsaOaepSupported() const {
+    return pk11_pub_encrypt_func_ && pk11_priv_decrypt_func_ &&
+           internal_slot_does_oaep_;
+  }
+
+  // Returns NULL if unsupported.
+  PK11_EncryptDecryptFunction pk11_encrypt_func() const {
+    return pk11_encrypt_func_;
+  }
+
+  // Returns NULL if unsupported.
+  PK11_EncryptDecryptFunction pk11_decrypt_func() const {
+    return pk11_decrypt_func_;
+  }
+
+  // Returns NULL if unsupported.
+  PK11_PubEncryptFunction pk11_pub_encrypt_func() const {
+    return pk11_pub_encrypt_func_;
+  }
+
+  // Returns NULL if unsupported.
+  PK11_PrivDecryptFunction pk11_priv_decrypt_func() const {
+    return pk11_priv_decrypt_func_;
+  }
+
+  static NssRuntimeSupport* Get();
+
+ private:
+  friend struct base::DefaultLazyInstanceTraits<NssRuntimeSupport>;
+
+  NssRuntimeSupport();
+
+  PK11_EncryptDecryptFunction pk11_encrypt_func_;
+  PK11_EncryptDecryptFunction pk11_decrypt_func_;
+  PK11_PubEncryptFunction pk11_pub_encrypt_func_;
+  PK11_PrivDecryptFunction pk11_priv_decrypt_func_;
+  bool internal_slot_does_oaep_;
+};
+
+}  // namespace webcrypto
+
+}  // namespace content
+
+#endif  // CONTENT_CHILD_WEBCRYPTO_NSS_UTIL_NSS_H_