[webcrypto] Some fixes for HMAC

content/renderer/webcrypto/webcrypto_util.cc

 // Copyright 2013 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/renderer/webcrypto/webcrypto_util.h"
 
 #include "base/base64.h"
 #include "base/logging.h"
 #include "third_party/WebKit/public/platform/WebCryptoAlgorithm.h"
 #include "third_party/WebKit/public/platform/WebCryptoAlgorithmParams.h"
@@ skipping 154 matching lines @@
   return CreateAesKeyGenAlgorithm(blink::WebCryptoAlgorithmIdAesCbc,
                                   key_length_bits);
 }
 
 blink::WebCryptoAlgorithm CreateAesGcmKeyGenAlgorithm(
     unsigned short key_length_bits) {
   return CreateAesKeyGenAlgorithm(blink::WebCryptoAlgorithmIdAesGcm,
                                   key_length_bits);
 }
 
+unsigned int ShaBlockSizeBytes(blink::WebCryptoAlgorithmId hash_id) {
+  switch (hash_id) {
+    case blink::WebCryptoAlgorithmIdSha1:
+    case blink::WebCryptoAlgorithmIdSha224:
+    case blink::WebCryptoAlgorithmIdSha256:
+      return 64;
+    case blink::WebCryptoAlgorithmIdSha384:
+    case blink::WebCryptoAlgorithmIdSha512:
+      return 128;
+    default:
+      NOTREACHED();
+      return 0;
+  }
+}
+
 }  // namespace webcrypto
 
 }  // namespace content