summaryrefslogtreecommitdiff
path: root/crypto/hmac.h
diff options
context:
space:
mode:
Diffstat (limited to 'crypto/hmac.h')
-rw-r--r--crypto/hmac.h93
1 files changed, 0 insertions, 93 deletions
diff --git a/crypto/hmac.h b/crypto/hmac.h
deleted file mode 100644
index c7b22fa1bd..0000000000
--- a/crypto/hmac.h
+++ /dev/null
@@ -1,93 +0,0 @@
-// Copyright (c) 2012 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 CRYPTO_HMAC_H_
-#define CRYPTO_HMAC_H_
-
-#include "base/basictypes.h"
-#include "base/compiler_specific.h"
-#include "base/memory/scoped_ptr.h"
-#include "base/strings/string_piece.h"
-#include "crypto/crypto_export.h"
-
-namespace crypto {
-
-// Simplify the interface and reduce includes by abstracting out the internals.
-struct HMACPlatformData;
-class SymmetricKey;
-
-class CRYPTO_EXPORT HMAC {
- public:
- // The set of supported hash functions. Extend as required.
- enum HashAlgorithm {
- SHA1,
- SHA256,
- };
-
- explicit HMAC(HashAlgorithm hash_alg);
- ~HMAC();
-
- // Returns the length of digest that this HMAC will create.
- size_t DigestLength() const;
-
- // TODO(abarth): Add a PreferredKeyLength() member function.
-
- // Initializes this instance using |key| of the length |key_length|. Call Init
- // only once. It returns false on the second or later calls.
- //
- // NOTE: the US Federal crypto standard FIPS 198, Section 3 says:
- // The size of the key, K, shall be equal to or greater than L/2, where L
- // is the size of the hash function output.
- // In FIPS 198-1 (and SP-800-107, which describes key size recommendations),
- // this requirement is gone. But a system crypto library may still enforce
- // this old requirement. If the key is shorter than this recommended value,
- // Init() may fail.
- bool Init(const unsigned char* key, size_t key_length) WARN_UNUSED_RESULT;
-
- // Initializes this instance using |key|. Call Init
- // only once. It returns false on the second or later calls.
- bool Init(SymmetricKey* key) WARN_UNUSED_RESULT;
-
- // Initializes this instance using |key|. Call Init only once. It returns
- // false on the second or later calls.
- bool Init(const base::StringPiece& key) WARN_UNUSED_RESULT {
- return Init(reinterpret_cast<const unsigned char*>(key.data()),
- key.size());
- }
-
- // Calculates the HMAC for the message in |data| using the algorithm supplied
- // to the constructor and the key supplied to the Init method. The HMAC is
- // returned in |digest|, which has |digest_length| bytes of storage available.
- bool Sign(const base::StringPiece& data, unsigned char* digest,
- size_t digest_length) const WARN_UNUSED_RESULT;
-
- // Verifies that the HMAC for the message in |data| equals the HMAC provided
- // in |digest|, using the algorithm supplied to the constructor and the key
- // supplied to the Init method. Use of this method is strongly recommended
- // over using Sign() with a manual comparison (such as memcmp), as such
- // comparisons may result in side-channel disclosures, such as timing, that
- // undermine the cryptographic integrity. |digest| must be exactly
- // |DigestLength()| bytes long.
- bool Verify(const base::StringPiece& data,
- const base::StringPiece& digest) const WARN_UNUSED_RESULT;
-
- // Verifies a truncated HMAC, behaving identical to Verify(), except
- // that |digest| is allowed to be smaller than |DigestLength()|.
- bool VerifyTruncated(
- const base::StringPiece& data,
- const base::StringPiece& digest) const WARN_UNUSED_RESULT;
-
- private:
- HashAlgorithm hash_alg_;
- scoped_ptr<HMACPlatformData> plat_;
-
- DISALLOW_COPY_AND_ASSIGN(HMAC);
-};
-
-} // namespace crypto
-
-#endif // CRYPTO_HMAC_H_