libcruft-util/hash/hmac.cpp
Danny Robson 9a798446b5 build: remove unnecessary includes
discovered with include-what-you-use
2016-10-12 15:08:22 +11:00

125 lines
3.1 KiB
C++

/*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* Copyright 2015 Danny Robson <danny@nerdcruft.net>
*/
#include "hmac.hpp"
#include "../debug.hpp"
#include <algorithm>
using util::hash::HMAC;
//-----------------------------------------------------------------------------
static const uint8_t IFILL = 0x36;
static const uint8_t OFILL = 0x5C;
//-----------------------------------------------------------------------------
template <class T>
HMAC<T>::HMAC (const uint8_t *restrict key, size_t len)
{
CHECK (key);
static_assert (sizeof (m_ikey) == sizeof (m_okey), "key padding must match");
// If the key is larger than the blocklength, use the hash of the key
if (len > T::BLOCK_SIZE) {
m_hash.update (key, len);
m_hash.finish ();
auto d = m_hash.digest ();
m_hash.reset ();
std::copy (d.begin (), d.end (), m_ikey.begin ());
len = d.size ();
// Use the key directly
} else {
std::copy (key, key + len, m_ikey.begin ());
}
std::fill (m_ikey.begin () + len,
m_ikey.end (),
0);
m_okey = m_ikey;
std::transform (m_ikey.begin (),
m_ikey.end (),
m_ikey.begin (),
[] (auto v) { return v ^ IFILL; });
std::transform (m_okey.begin (),
m_okey.end (),
m_okey.begin (),
[] (auto v) { return v ^ OFILL; });
m_hash.update (m_ikey.data (), m_ikey.size ());
}
//-----------------------------------------------------------------------------
template <class T>
void
HMAC<T>::update (const void *restrict data, size_t len)
{
m_hash.update ((const uint8_t*)data, len);
}
//-----------------------------------------------------------------------------
template <class T>
void
HMAC<T>::finish (void)
{
m_hash.finish ();
auto d = m_hash.digest ();
m_hash.reset ();
m_hash.update (m_okey.data (), m_okey.size ());
m_hash.update (d.data (), d.size ());
m_hash.finish ();
}
//-----------------------------------------------------------------------------
template <class T>
void
HMAC<T>::reset (void)
{
m_hash.reset ();
m_hash.update (m_ikey.data (), m_ikey.size ());
}
//-----------------------------------------------------------------------------
template <class T>
typename HMAC<T>::digest_t
HMAC<T>::digest (void)
{
return m_hash.digest ();
}
//-----------------------------------------------------------------------------
#include "md5.hpp"
#include "sha1.hpp"
namespace util::hash {
template class HMAC<MD5>;
template class HMAC<SHA1>;
}