Refactor: Extract common code for generating asymmetric keys to a helper.

content/child/webcrypto/webcrypto_util.cc

 // 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.
 
 #include "content/child/webcrypto/webcrypto_util.h"
 
 #include <set>
 
 #include "base/logging.h"
 #include "base/numerics/safe_math.h"
@@ skipping 363 matching lines @@
     *length_bits = params->optionalLengthBits();
     if (*length_bits == 0)
       return Status::ErrorGetHmacKeyLengthZero();
     return Status::Success();
   }
 
   *has_length_bits = true;
   return GetShaBlockSizeBits(params->hash(), length_bits);
 }
 
+Status GetUsagesForGenerateAsymmetricKey(
+    blink::WebCryptoKeyUsageMask combined_usages,
+    blink::WebCryptoKeyUsageMask all_public_usages,
+    blink::WebCryptoKeyUsageMask all_private_usages,
+    blink::WebCryptoKeyUsageMask* public_usages,
+    blink::WebCryptoKeyUsageMask* private_usages) {
+  Status status = CheckKeyCreationUsages(all_public_usages | all_private_usages,
+                                         combined_usages);
+  if (status.IsError())
+    return status;
+
+  *public_usages = combined_usages & all_public_usages;
+  *private_usages = combined_usages & all_private_usages;
+
+  if (*private_usages == 0)
+    return Status::ErrorCreateKeyEmptyUsages();
+
+  return Status::Success();
+}
+
 }  // namespace webcrypto
 
 }  // namespace content