HMAC-SHA1 implementation for Mac based on CommonCrypto;
allow Windows HMAC-SHA1 to use keys longer than 16 bytes.
Review URL: http://codereview.chromium.org/218
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@1724 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/base/hmac.h b/base/hmac.h
index dac4e82..f9c0e604 100644
--- a/base/hmac.h
+++ b/base/hmac.h
@@ -1,20 +1,26 @@
// Copyright (c) 2006-2008 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.
-//
+
// Utility class for calculating the HMAC for a given message. We currently
// only support SHA1 for the hash algorithm, but this can be extended easily.
-#ifndef BASE_HMAC_H__
-#define BASE_HMAC_H__
+#ifndef BASE_HMAC_H_
+#define BASE_HMAC_H_
+#include "build/build_config.h"
+
+#if defined(OS_WIN)
#include <windows.h>
#include <wincrypt.h>
+#endif
#include <string>
#include "base/basictypes.h"
+namespace base {
+
class HMAC {
public:
// The set of supported hash functions. Extend as required.
@@ -25,16 +31,17 @@
HMAC(HashAlgorithm hash_alg, const unsigned char* key, int key_length);
~HMAC();
- // Returns the HMAC in 'digest' for the message in 'data' and the key
- // specified in the contructor.
+ // Calculates the HMAC for the message in |data| using the algorithm and key
+ // supplied to the constructor. The HMAC is returned in |digest|, which
+ // has |digest_length| bytes of storage available.
bool Sign(const std::string& data, unsigned char* digest, int digest_length);
private:
+#if defined(OS_POSIX)
+ HashAlgorithm hash_alg_;
+ std::string key_;
+#elif defined(OS_WIN)
// Import the key so that we don't have to store it ourself.
- // TODO(paulg): Bug: http://b/1084719, 'ImportKey' will not currently work on
- // Windows 2000 since it requires special handling for importing
- // keys. See this link for details:
- // http://www.derkeiler.com/Newsgroups/microsoft.public.platformsdk.security/2004-06/0270.html
void ImportKey(const unsigned char* key, int key_length);
// Returns the SHA1 hash of 'data' and 'key' in 'digest'. If there was any
@@ -43,10 +50,6 @@
unsigned char* digest,
int digest_length);
- // Required for the SHA1 key_blob struct. We limit this to 16 bytes since
- // Windows 2000 doesn't support keys larger than that.
- static const int kMaxKeySize = 16;
-
// The hash algorithm to use.
HashAlgorithm hash_alg_;
@@ -54,10 +57,11 @@
HCRYPTPROV provider_;
HCRYPTHASH hash_;
HCRYPTKEY hkey_;
+#endif // OS_WIN
- DISALLOW_EVIL_CONSTRUCTORS(HMAC);
+ DISALLOW_COPY_AND_ASSIGN(HMAC);
};
+} // namespace base
-#endif // BASE_HMAC_H__
-
+#endif // BASE_HMAC_H_
