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-rw-r--r--CryptoPP/iterhash.cpp160
1 files changed, 160 insertions, 0 deletions
diff --git a/CryptoPP/iterhash.cpp b/CryptoPP/iterhash.cpp
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+++ b/CryptoPP/iterhash.cpp
@@ -0,0 +1,160 @@
+// iterhash.cpp - written and placed in the public domain by Wei Dai
+
+#ifndef __GNUC__
+#define CRYPTOPP_MANUALLY_INSTANTIATE_TEMPLATES
+#endif
+
+#include "iterhash.h"
+#include "misc.h"
+
+NAMESPACE_BEGIN(CryptoPP)
+
+template <class T, class BASE> void IteratedHashBase<T, BASE>::Update(const byte *input, size_t len)
+{
+ HashWordType oldCountLo = m_countLo, oldCountHi = m_countHi;
+ if ((m_countLo = oldCountLo + HashWordType(len)) < oldCountLo)
+ m_countHi++; // carry from low to high
+ m_countHi += (HashWordType)SafeRightShift<8*sizeof(HashWordType)>(len);
+ if (m_countHi < oldCountHi || SafeRightShift<2*8*sizeof(HashWordType)>(len) != 0)
+ throw HashInputTooLong(this->AlgorithmName());
+
+ unsigned int blockSize = this->BlockSize();
+ unsigned int num = ModPowerOf2(oldCountLo, blockSize);
+ T* dataBuf = this->DataBuf();
+ byte* data = (byte *)dataBuf;
+
+ if (num != 0) // process left over data
+ {
+ if (num+len >= blockSize)
+ {
+ memcpy(data+num, input, blockSize-num);
+ HashBlock(dataBuf);
+ input += (blockSize-num);
+ len -= (blockSize-num);
+ num = 0;
+ // drop through and do the rest
+ }
+ else
+ {
+ memcpy(data+num, input, len);
+ return;
+ }
+ }
+
+ // now process the input data in blocks of blockSize bytes and save the leftovers to m_data
+ if (len >= blockSize)
+ {
+ if (input == data)
+ {
+ assert(len == blockSize);
+ HashBlock(dataBuf);
+ return;
+ }
+ else if (IsAligned<T>(input))
+ {
+ size_t leftOver = HashMultipleBlocks((T *)input, len);
+ input += (len - leftOver);
+ len = leftOver;
+ }
+ else
+ do
+ { // copy input first if it's not aligned correctly
+ memcpy(data, input, blockSize);
+ HashBlock(dataBuf);
+ input+=blockSize;
+ len-=blockSize;
+ } while (len >= blockSize);
+ }
+
+ if (len && data != input)
+ memcpy(data, input, len);
+}
+
+template <class T, class BASE> byte * IteratedHashBase<T, BASE>::CreateUpdateSpace(size_t &size)
+{
+ unsigned int blockSize = this->BlockSize();
+ unsigned int num = ModPowerOf2(m_countLo, blockSize);
+ size = blockSize - num;
+ return (byte *)DataBuf() + num;
+}
+
+template <class T, class BASE> size_t IteratedHashBase<T, BASE>::HashMultipleBlocks(const T *input, size_t length)
+{
+ unsigned int blockSize = this->BlockSize();
+ bool noReverse = NativeByteOrderIs(this->GetByteOrder());
+ T* dataBuf = this->DataBuf();
+ do
+ {
+ if (noReverse)
+ this->HashEndianCorrectedBlock(input);
+ else
+ {
+ ByteReverse(dataBuf, input, this->BlockSize());
+ this->HashEndianCorrectedBlock(dataBuf);
+ }
+
+ input += blockSize/sizeof(T);
+ length -= blockSize;
+ }
+ while (length >= blockSize);
+ return length;
+}
+
+template <class T, class BASE> void IteratedHashBase<T, BASE>::PadLastBlock(unsigned int lastBlockSize, byte padFirst)
+{
+ unsigned int blockSize = this->BlockSize();
+ unsigned int num = ModPowerOf2(m_countLo, blockSize);
+ T* dataBuf = this->DataBuf();
+ byte* data = (byte *)dataBuf;
+ data[num++] = padFirst;
+ if (num <= lastBlockSize)
+ memset(data+num, 0, lastBlockSize-num);
+ else
+ {
+ memset(data+num, 0, blockSize-num);
+ HashBlock(dataBuf);
+ memset(data, 0, lastBlockSize);
+ }
+}
+
+template <class T, class BASE> void IteratedHashBase<T, BASE>::Restart()
+{
+ m_countLo = m_countHi = 0;
+ Init();
+}
+
+template <class T, class BASE> void IteratedHashBase<T, BASE>::TruncatedFinal(byte *digest, size_t size)
+{
+ this->ThrowIfInvalidTruncatedSize(size);
+
+ T* dataBuf = this->DataBuf();
+ T* stateBuf = this->StateBuf();
+ unsigned int blockSize = this->BlockSize();
+ ByteOrder order = this->GetByteOrder();
+
+ PadLastBlock(blockSize - 2*sizeof(HashWordType));
+ dataBuf[blockSize/sizeof(T)-2+order] = ConditionalByteReverse(order, this->GetBitCountLo());
+ dataBuf[blockSize/sizeof(T)-1-order] = ConditionalByteReverse(order, this->GetBitCountHi());
+
+ HashBlock(dataBuf);
+
+ if (IsAligned<HashWordType>(digest) && size%sizeof(HashWordType)==0)
+ ConditionalByteReverse<HashWordType>(order, (HashWordType *)digest, stateBuf, size);
+ else
+ {
+ ConditionalByteReverse<HashWordType>(order, stateBuf, stateBuf, this->DigestSize());
+ memcpy(digest, stateBuf, size);
+ }
+
+ this->Restart(); // reinit for next use
+}
+
+#ifdef __GNUC__
+ template class IteratedHashBase<word64, HashTransformation>;
+ template class IteratedHashBase<word64, MessageAuthenticationCode>;
+
+ template class IteratedHashBase<word32, HashTransformation>;
+ template class IteratedHashBase<word32, MessageAuthenticationCode>;
+#endif
+
+NAMESPACE_END