[refactor] Use base::CheckedNumeric<> in place of manual checks.

content/child/webcrypto/nss/rsa_key_nss.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/nss/rsa_key_nss.h"
 
 #include "base/logging.h"
+#include "base/numerics/safe_math.h"
 #include "content/child/webcrypto/crypto_data.h"
 #include "content/child/webcrypto/jwk.h"
 #include "content/child/webcrypto/nss/key_nss.h"
 #include "content/child/webcrypto/nss/util_nss.h"
 #include "content/child/webcrypto/status.h"
 #include "content/child/webcrypto/webcrypto_util.h"
 #include "crypto/scoped_nss_types.h"
 #include "third_party/WebKit/public/platform/WebCryptoAlgorithmParams.h"
 #include "third_party/WebKit/public/platform/WebCryptoKeyAlgorithm.h"
 
@@ skipping 573 matching lines @@
       (public_exponent != 3 && public_exponent != 65537)) {
     return Status::ErrorGenerateKeyPublicExponent();
   }
 
   crypto::ScopedPK11Slot slot(PK11_GetInternalKeySlot());
   if (!slot)
     return Status::OperationError();
 
   PK11RSAGenParams rsa_gen_params;
   // keySizeInBits is a signed type, don't pass in a negative value.
-  if (params->modulusLengthBits() > INT_MAX)
+  base::CheckedNumeric<int> signed_modulus(params->modulusLengthBits());
+  if (!signed_modulus.IsValid())
     return Status::OperationError();
-  rsa_gen_params.keySizeInBits = params->modulusLengthBits();
+  rsa_gen_params.keySizeInBits = signed_modulus.ValueOrDie();
   rsa_gen_params.pe = public_exponent;
 
   const CK_FLAGS operation_flags_mask =
       CKF_ENCRYPT | CKF_DECRYPT | CKF_SIGN | CKF_VERIFY | CKF_WRAP | CKF_UNWRAP;
 
   // The private key must be marked as insensitive and extractable, otherwise it
   // cannot later be exported in unencrypted form or structured-cloned.
   const PK11AttrFlags attribute_flags =
       PK11_ATTR_INSENSITIVE | PK11_ATTR_EXTRACTABLE;
 
@@ skipping 274 matching lines @@
       return Status::Success();
     }
     default:
       return Status::ErrorUnexpected();
   }
 }
 
 }  // namespace webcrypto
 
 }  // namespace content