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Diffstat (limited to 'CryptoPP/seal.cpp')
| -rw-r--r-- | CryptoPP/seal.cpp | 213 |
1 files changed, 213 insertions, 0 deletions
diff --git a/CryptoPP/seal.cpp b/CryptoPP/seal.cpp new file mode 100644 index 000000000..f49b52203 --- /dev/null +++ b/CryptoPP/seal.cpp @@ -0,0 +1,213 @@ +// seal.cpp - written and placed in the public domain by Wei Dai +// updated to SEAL 3.0 by Leonard Janke + +#include "pch.h" + +#include "seal.h" +#include "sha.h" +#include "misc.h" + +NAMESPACE_BEGIN(CryptoPP) + +void SEAL_TestInstantiations() +{ + SEAL<>::Encryption x; +} + +struct SEAL_Gamma +{ + SEAL_Gamma(const byte *key) + : H(5), Z(5), D(16), lastIndex(0xffffffff) + { + GetUserKey(BIG_ENDIAN_ORDER, H.begin(), 5, key, 20); + memset(D, 0, 64); + } + + word32 Apply(word32 i); + + SecBlock<word32> H, Z, D; + word32 lastIndex; +}; + +word32 SEAL_Gamma::Apply(word32 i) +{ + word32 shaIndex = i/5; + if (shaIndex != lastIndex) + { + memcpy(Z, H, 20); + D[0] = shaIndex; + SHA::Transform(Z, D); + lastIndex = shaIndex; + } + return Z[i%5]; +} + +template <class B> +void SEAL_Policy<B>::CipherSetKey(const NameValuePairs ¶ms, const byte *key, size_t length) +{ + m_insideCounter = m_outsideCounter = m_startCount = 0; + + unsigned int L = params.GetIntValueWithDefault("NumberOfOutputBitsPerPositionIndex", 32*1024); + m_iterationsPerCount = L / 8192; + + SEAL_Gamma gamma(key); + unsigned int i; + + for (i=0; i<512; i++) + m_T[i] = gamma.Apply(i); + + for (i=0; i<256; i++) + m_S[i] = gamma.Apply(0x1000+i); + + m_R.New(4*(L/8192)); + + for (i=0; i<m_R.size(); i++) + m_R[i] = gamma.Apply(0x2000+i); +} + +template <class B> +void SEAL_Policy<B>::CipherResynchronize(byte *keystreamBuffer, const byte *IV, size_t length) +{ + assert(length==4); + m_outsideCounter = IV ? GetWord<word32>(false, BIG_ENDIAN_ORDER, IV) : 0; + m_startCount = m_outsideCounter; + m_insideCounter = 0; +} + +template <class B> +void SEAL_Policy<B>::SeekToIteration(lword iterationCount) +{ + m_outsideCounter = m_startCount + (unsigned int)(iterationCount / m_iterationsPerCount); + m_insideCounter = (unsigned int)(iterationCount % m_iterationsPerCount); +} + +template <class B> +void SEAL_Policy<B>::OperateKeystream(KeystreamOperation operation, byte *output, const byte *input, size_t iterationCount) +{ + word32 a, b, c, d, n1, n2, n3, n4; + unsigned int p, q; + + for (size_t iteration = 0; iteration < iterationCount; ++iteration) + { +#define Ttab(x) *(word32 *)((byte *)m_T.begin()+x) + + a = m_outsideCounter ^ m_R[4*m_insideCounter]; + b = rotrFixed(m_outsideCounter, 8U) ^ m_R[4*m_insideCounter+1]; + c = rotrFixed(m_outsideCounter, 16U) ^ m_R[4*m_insideCounter+2]; + d = rotrFixed(m_outsideCounter, 24U) ^ m_R[4*m_insideCounter+3]; + + for (unsigned int j=0; j<2; j++) + { + p = a & 0x7fc; + b += Ttab(p); + a = rotrFixed(a, 9U); + + p = b & 0x7fc; + c += Ttab(p); + b = rotrFixed(b, 9U); + + p = c & 0x7fc; + d += Ttab(p); + c = rotrFixed(c, 9U); + + p = d & 0x7fc; + a += Ttab(p); + d = rotrFixed(d, 9U); + } + + n1 = d, n2 = b, n3 = a, n4 = c; + + p = a & 0x7fc; + b += Ttab(p); + a = rotrFixed(a, 9U); + + p = b & 0x7fc; + c += Ttab(p); + b = rotrFixed(b, 9U); + + p = c & 0x7fc; + d += Ttab(p); + c = rotrFixed(c, 9U); + + p = d & 0x7fc; + a += Ttab(p); + d = rotrFixed(d, 9U); + + // generate 8192 bits + for (unsigned int i=0; i<64; i++) + { + p = a & 0x7fc; + a = rotrFixed(a, 9U); + b += Ttab(p); + b ^= a; + + q = b & 0x7fc; + b = rotrFixed(b, 9U); + c ^= Ttab(q); + c += b; + + p = (p+c) & 0x7fc; + c = rotrFixed(c, 9U); + d += Ttab(p); + d ^= c; + + q = (q+d) & 0x7fc; + d = rotrFixed(d, 9U); + a ^= Ttab(q); + a += d; + + p = (p+a) & 0x7fc; + b ^= Ttab(p); + a = rotrFixed(a, 9U); + + q = (q+b) & 0x7fc; + c += Ttab(q); + b = rotrFixed(b, 9U); + + p = (p+c) & 0x7fc; + d ^= Ttab(p); + c = rotrFixed(c, 9U); + + q = (q+d) & 0x7fc; + d = rotrFixed(d, 9U); + a += Ttab(q); + +#define SEAL_OUTPUT(x) \ + CRYPTOPP_KEYSTREAM_OUTPUT_WORD(x, B::ToEnum(), 0, b + m_S[4*i+0]);\ + CRYPTOPP_KEYSTREAM_OUTPUT_WORD(x, B::ToEnum(), 1, c ^ m_S[4*i+1]);\ + CRYPTOPP_KEYSTREAM_OUTPUT_WORD(x, B::ToEnum(), 2, d + m_S[4*i+2]);\ + CRYPTOPP_KEYSTREAM_OUTPUT_WORD(x, B::ToEnum(), 3, a ^ m_S[4*i+3]); + + CRYPTOPP_KEYSTREAM_OUTPUT_SWITCH(SEAL_OUTPUT, 4*4); + + if (i & 1) + { + a += n3; + b += n4; + c ^= n3; + d ^= n4; + } + else + { + a += n1; + b += n2; + c ^= n1; + d ^= n2; + } + } + + if (++m_insideCounter == m_iterationsPerCount) + { + ++m_outsideCounter; + m_insideCounter = 0; + } + } + + a = b = c = d = n1 = n2 = n3 = n4 = 0; + p = q = 0; +} + +template class SEAL_Policy<BigEndian>; +template class SEAL_Policy<LittleEndian>; + +NAMESPACE_END |