[webcrypto] Add length parameter to HmacKeyAlgorithm. (chromium)

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 "base/base64.h"
 #include "base/logging.h"
 #include "base/strings/stringprintf.h"
 #include "third_party/WebKit/public/platform/WebCryptoAlgorithm.h"
@@ skipping 367 matching lines @@
 
 bool CreateSecretKeyAlgorithm(const blink::WebCryptoAlgorithm& algorithm,
                               unsigned keylen_bytes,
                               blink::WebCryptoKeyAlgorithm* key_algorithm) {
   switch (algorithm.id()) {
     case blink::WebCryptoAlgorithmIdHmac: {
       blink::WebCryptoAlgorithm hash = GetInnerHashAlgorithm(algorithm);
       if (hash.isNull())
         return false;
       *key_algorithm = blink::WebCryptoKeyAlgorithm::adoptParamsAndCreate(
-          algorithm.id(), new blink::WebCryptoHmacKeyAlgorithmParams(hash));
+          algorithm.id(),
+#if defined(WEBCRYPTO_HMAC_KEY_HAS_LENGTH)
+          new blink::WebCryptoHmacKeyAlgorithmParams(hash, keylen_bytes * 8));

[eroman, 2014/03/18 23:50:01]

I didn't check for overflow, probably should. wdyt?

[eroman, 2014/03/19 00:04:19]

OK done.

+#else
+          new blink::WebCryptoHmacKeyAlgorithmParams(hash));
+#endif
       return true;
     }
     case blink::WebCryptoAlgorithmIdAesKw:
     case blink::WebCryptoAlgorithmIdAesCbc:
     case blink::WebCryptoAlgorithmIdAesCtr:
     case blink::WebCryptoAlgorithmIdAesGcm:
       *key_algorithm = blink::WebCryptoKeyAlgorithm::adoptParamsAndCreate(
           algorithm.id(),
           new blink::WebCryptoAesKeyAlgorithmParams(keylen_bytes * 8));
       return true;
     default:
       return false;
   }
 }
 
 }  // namespace webcrypto
 
 }  // namespace content