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by weidai
Initial revision |
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// tea.cpp - modified by Wei Dai from code in the original paper
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#include "pch.h" |
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#include "tea.h" |
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#include "misc.h" |
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NAMESPACE_BEGIN(CryptoPP) |
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107
by weidai
add XTEA and BTEA |
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static const word32 DELTA = 0x9e3779b9; |
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typedef BlockGetAndPut<word32, BigEndian> Block; |
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1
by weidai
Initial revision |
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232
by weidai
port to GCC 4, reorganize implementations of SetKey |
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void TEA::Base::UncheckedSetKey(const byte *userKey, unsigned int length, const NameValuePairs ¶ms) |
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by weidai
Initial revision |
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{
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AssertValidKeyLength(length); |
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107
by weidai
add XTEA and BTEA |
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GetUserKey(BIG_ENDIAN_ORDER, m_k.begin(), 4, userKey, KEYLENGTH); |
232
by weidai
port to GCC 4, reorganize implementations of SetKey |
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m_limit = GetRoundsAndThrowIfInvalid(params, this) * DELTA; |
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by weidai
Initial revision |
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}
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void TEA::Enc::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const |
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{
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word32 y, z; |
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Block::Get(inBlock)(y)(z); |
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word32 sum = 0; |
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107
by weidai
add XTEA and BTEA |
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while (sum != m_limit) |
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by weidai
Initial revision |
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{
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sum += DELTA; |
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by weidai
add XTEA and BTEA |
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y += (z << 4) + m_k[0] ^ z + sum ^ (z >> 5) + m_k[1]; |
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z += (y << 4) + m_k[2] ^ y + sum ^ (y >> 5) + m_k[3]; |
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by weidai
Initial revision |
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}
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Block::Put(xorBlock, outBlock)(y)(z); |
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}
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void TEA::Dec::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const |
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{
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word32 y, z; |
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Block::Get(inBlock)(y)(z); |
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107
by weidai
add XTEA and BTEA |
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word32 sum = m_limit; |
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while (sum != 0) |
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{
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z -= (y << 4) + m_k[2] ^ y + sum ^ (y >> 5) + m_k[3]; |
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y -= (z << 4) + m_k[0] ^ z + sum ^ (z >> 5) + m_k[1]; |
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sum -= DELTA; |
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}
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Block::Put(xorBlock, outBlock)(y)(z); |
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}
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232
by weidai
port to GCC 4, reorganize implementations of SetKey |
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void XTEA::Base::UncheckedSetKey(const byte *userKey, unsigned int length, const NameValuePairs ¶ms) |
107
by weidai
add XTEA and BTEA |
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{
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AssertValidKeyLength(length); |
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GetUserKey(BIG_ENDIAN_ORDER, m_k.begin(), 4, userKey, KEYLENGTH); |
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232
by weidai
port to GCC 4, reorganize implementations of SetKey |
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m_limit = GetRoundsAndThrowIfInvalid(params, this) * DELTA; |
107
by weidai
add XTEA and BTEA |
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}
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void XTEA::Enc::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const |
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{
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word32 y, z; |
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Block::Get(inBlock)(y)(z); |
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word32 sum = 0; |
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while (sum != m_limit) |
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{
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y += (z<<4 ^ z>>5) + z ^ sum + m_k[sum&3]; |
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sum += DELTA; |
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z += (y<<4 ^ y>>5) + y ^ sum + m_k[sum>>11 & 3]; |
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}
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Block::Put(xorBlock, outBlock)(y)(z); |
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}
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void XTEA::Dec::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const |
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{
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word32 y, z; |
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Block::Get(inBlock)(y)(z); |
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word32 sum = m_limit; |
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while (sum != 0) |
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{
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z -= (y<<4 ^ y>>5) + y ^ sum + m_k[sum>>11 & 3]; |
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sum -= DELTA; |
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y -= (z<<4 ^ z>>5) + z ^ sum + m_k[sum&3]; |
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}
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Block::Put(xorBlock, outBlock)(y)(z); |
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}
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#define MX (z>>5^y<<2)+(y>>3^z<<4)^(sum^y)+(m_k[p&3^e]^z)
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void BTEA::Enc::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const |
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{
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unsigned int n = m_blockSize / 4; |
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word32 *v = (word32*)outBlock; |
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ConditionalByteReverse(BIG_ENDIAN_ORDER, v, (const word32*)inBlock, m_blockSize); |
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word32 y = v[0], z = v[n-1], e; |
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word32 p, q = 6+52/n; |
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word32 sum = 0; |
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while (q-- > 0) |
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{
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sum += DELTA; |
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e = sum>>2 & 3; |
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for (p = 0; p < n-1; p++) |
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{
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y = v[p+1]; |
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z = v[p] += MX; |
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}
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y = v[0]; |
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z = v[n-1] += MX; |
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}
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ConditionalByteReverse(BIG_ENDIAN_ORDER, v, v, m_blockSize); |
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}
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void BTEA::Dec::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const |
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{
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unsigned int n = m_blockSize / 4; |
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word32 *v = (word32*)outBlock; |
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ConditionalByteReverse(BIG_ENDIAN_ORDER, v, (const word32*)inBlock, m_blockSize); |
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word32 y = v[0], z = v[n-1], e; |
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word32 p, q = 6+52/n; |
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word32 sum = q * DELTA; |
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while (sum != 0) |
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{
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e = sum>>2 & 3; |
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for (p = n-1; p > 0; p--) |
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{
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z = v[p-1]; |
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y = v[p] -= MX; |
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}
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z = v[n-1]; |
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y = v[0] -= MX; |
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sum -= DELTA; |
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}
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ConditionalByteReverse(BIG_ENDIAN_ORDER, v, v, m_blockSize); |
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1
by weidai
Initial revision |
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}
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NAMESPACE_END
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