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  • Committer: Bazaar Package Importer
  • Author(s): Pierre Machard
  • Date: 2004-08-27 12:35:05 UTC
  • mfrom: (1.1.1 upstream)
  • Revision ID: james.westby@ubuntu.com-20040827123505-7evgxiu7k8memiyk
Tags: 5.2.1a-1
* Urgency set to high because lastest upload was unclean
* Rename libcrypto++-5.2.1.orig.tar.gz in  libcrypto++-5.2.1a.orig.tar.gz

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hmac.cpp
 
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// hmac.cpp - written and placed in the public domain by Wei Dai
 
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#include "pch.h"
 
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#ifndef CRYPTOPP_IMPORTS
 
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#include "hmac.h"
 
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NAMESPACE_BEGIN(CryptoPP)
 
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void HMAC_Base::UncheckedSetKey(const byte *userKey, unsigned int keylength)
 
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{
 
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        AssertValidKeyLength(keylength);
 
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        Restart();
 
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        HashTransformation &hash = AccessHash();
 
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        unsigned int blockSize = hash.BlockSize();
 
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        if (!blockSize)
 
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                throw InvalidArgument("HMAC: can only be used with a block-based hash function");
 
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        if (keylength <= blockSize)
 
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                memcpy(AccessIpad(), userKey, keylength);
 
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        else
 
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        {
 
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                AccessHash().CalculateDigest(AccessIpad(), userKey, keylength);
 
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                keylength = hash.DigestSize();
 
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        }
 
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        assert(keylength <= blockSize);
 
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        memset(AccessIpad()+keylength, 0, blockSize-keylength);
 
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        for (unsigned int i=0; i<blockSize; i++)
 
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        {
 
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                AccessOpad()[i] = AccessIpad()[i] ^ OPAD;
 
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                AccessIpad()[i] ^= IPAD;
 
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        }
 
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}
 
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void HMAC_Base::KeyInnerHash()
 
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{
 
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        assert(!m_innerHashKeyed);
 
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        HashTransformation &hash = AccessHash();
 
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        hash.Update(AccessIpad(), hash.BlockSize());
 
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        m_innerHashKeyed = true;
 
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}
 
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void HMAC_Base::Restart()
 
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{
 
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        if (m_innerHashKeyed)
 
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        {
 
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                AccessHash().Restart();
 
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                m_innerHashKeyed = false;
 
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        }
 
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}
 
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void HMAC_Base::Update(const byte *input, unsigned int length)
 
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{
 
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        if (!m_innerHashKeyed)
 
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                KeyInnerHash();
 
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        AccessHash().Update(input, length);
 
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}
 
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void HMAC_Base::TruncatedFinal(byte *mac, unsigned int size)
 
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{
 
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        ThrowIfInvalidTruncatedSize(size);
 
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        HashTransformation &hash = AccessHash();
 
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        if (!m_innerHashKeyed)
 
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                KeyInnerHash();
 
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        hash.Final(AccessInnerHash());
 
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        hash.Update(AccessOpad(), hash.BlockSize());
 
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        hash.Update(AccessInnerHash(), hash.DigestSize());
 
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        hash.TruncatedFinal(mac, size);
 
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        m_innerHashKeyed = false;
 
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}
 
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NAMESPACE_END
 
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#endif