[webcrypto] Remove support for AES 192-bit keys (2 of 2)

content/child/webcrypto/shared_crypto.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/shared_crypto.h"
 
 #include "base/logging.h"
 #include "content/child/webcrypto/crypto_data.h"
 #include "content/child/webcrypto/jwk.h"
 #include "content/child/webcrypto/platform_crypto.h"
@@ skipping 201 matching lines @@
                     bool extractable,
                     blink::WebCryptoKeyUsageMask usage_mask,
                     blink::WebCryptoKey* key) {
   switch (algorithm.id()) {
     case blink::WebCryptoAlgorithmIdAesCtr:
     case blink::WebCryptoAlgorithmIdAesCbc:
     case blink::WebCryptoAlgorithmIdAesGcm:
     case blink::WebCryptoAlgorithmIdAesKw:
       if (!IsValidAesKeyLengthBytes(key_data.byte_length()))
         return Status::ErrorImportAesKeyLength();
+      if (key_data.byte_length() == 24 &&
+          algorithm.id() == blink::WebCryptoAlgorithmIdAesGcm) {
+        return Status::ErrorAesGcm192Unsupported();

[Ryan Sleevi, 2014/06/10 23:44:21]

Same comments re All AES

+      }
     // Fallthrough intentional!
     case blink::WebCryptoAlgorithmIdHmac:
       return platform::ImportKeyRaw(
           algorithm, key_data, extractable, usage_mask, key);
     default:
       return Status::ErrorUnsupported();
   }
 }
 
 // Returns the key format to use for structured cloning.
@@ skipping 423 matching lines @@
 
   // Get the secret key length in bytes from generation parameters.
   // This resolves any defaults.
   switch (algorithm.id()) {
     case blink::WebCryptoAlgorithmIdAesCbc:
     case blink::WebCryptoAlgorithmIdAesGcm:
     case blink::WebCryptoAlgorithmIdAesKw: {
       if (!IsValidAesKeyLengthBits(algorithm.aesKeyGenParams()->lengthBits()))
         return Status::ErrorGenerateKeyLength();
       keylen_bytes = algorithm.aesKeyGenParams()->lengthBits() / 8;
+
+      if (keylen_bytes == 24 &&
+          algorithm.id() == blink::WebCryptoAlgorithmIdAesGcm) {
+        return Status::ErrorAesGcm192Unsupported();
+      }

[Ryan Sleevi, 2014/06/10 23:44:21]

Same comments re All AES

+
       break;
     }
     case blink::WebCryptoAlgorithmIdHmac: {
       const blink::WebCryptoHmacKeyGenParams* params =
           algorithm.hmacKeyGenParams();
       DCHECK(params);
       if (params->hasLengthBits()) {
         if (params->optionalLengthBits() % 8)
           return Status::ErrorGenerateKeyLength();
         keylen_bytes = params->optionalLengthBits() / 8;
@@ skipping 310 matching lines @@
   if (!ContainsKeyUsages(GetValidKeyUsagesForKeyType(algorithm, key_type),
                          usages))
     return Status::ErrorCreateKeyBadUsages();
 
   return Status::Success();
 }
 
 }  // namespace webcrypto
 
 }  // namespace content