00001
00002
00003
00004 #include "pch.h"
00005
00006
00007 #if !(defined(__SUNPRO_CC) && defined(CRYPTOPP_ITERHASH_H))
00008
00009 #include "seal.h"
00010 #include "sha.h"
00011 #include "misc.h"
00012
00013 NAMESPACE_BEGIN(CryptoPP)
00014
00015 void SEAL_TestInstantiations()
00016 {
00017 SEAL<>::Encryption x;
00018 }
00019
00020 struct SEAL_Gamma
00021 {
00022 SEAL_Gamma(const byte *key)
00023 : H(5), Z(5), D(16), lastIndex(0xffffffff)
00024 {
00025 GetUserKey(BIG_ENDIAN_ORDER, H.begin(), 5, key, 20);
00026 memset(D, 0, 64);
00027 }
00028
00029 word32 Apply(word32 i);
00030
00031 SecBlock<word32> H, Z, D;
00032 word32 lastIndex;
00033 };
00034
00035 word32 SEAL_Gamma::Apply(word32 i)
00036 {
00037 word32 shaIndex = i/5;
00038 if (shaIndex != lastIndex)
00039 {
00040 memcpy(Z, H, 20);
00041 D[0] = shaIndex;
00042 SHA::Transform(Z, D);
00043 lastIndex = shaIndex;
00044 }
00045 return Z[i%5];
00046 }
00047
00048 template <class B>
00049 void SEAL_Policy<B>::CipherSetKey(const NameValuePairs ¶ms, const byte *key, size_t length)
00050 {
00051 m_insideCounter = m_outsideCounter = m_startCount = 0;
00052
00053 unsigned int L = params.GetIntValueWithDefault("NumberOfOutputBitsPerPositionIndex", 32*1024);
00054 m_iterationsPerCount = L / 8192;
00055
00056 SEAL_Gamma gamma(key);
00057 unsigned int i;
00058
00059 for (i=0; i<512; i++)
00060 m_T[i] = gamma.Apply(i);
00061
00062 for (i=0; i<256; i++)
00063 m_S[i] = gamma.Apply(0x1000+i);
00064
00065 m_R.New(4*(L/8192));
00066
00067 for (i=0; i<m_R.size(); i++)
00068 m_R[i] = gamma.Apply(0x2000+i);
00069 }
00070
00071 template <class B>
00072 void SEAL_Policy<B>::CipherResynchronize(byte *keystreamBuffer, const byte *IV)
00073 {
00074 m_outsideCounter = IV ? GetWord<word32>(false, BIG_ENDIAN_ORDER, IV) : 0;
00075 m_startCount = m_outsideCounter;
00076 m_insideCounter = 0;
00077 }
00078
00079 template <class B>
00080 void SEAL_Policy<B>::SeekToIteration(lword iterationCount)
00081 {
00082 m_outsideCounter = m_startCount + (unsigned int)(iterationCount / m_iterationsPerCount);
00083 m_insideCounter = (unsigned int)(iterationCount % m_iterationsPerCount);
00084 }
00085
00086 template <class B>
00087 void SEAL_Policy<B>::OperateKeystream(KeystreamOperation operation, byte *output, const byte *input, size_t iterationCount)
00088 {
00089 word32 a, b, c, d, n1, n2, n3, n4;
00090 unsigned int p, q;
00091
00092 for (size_t iteration = 0; iteration < iterationCount; ++iteration)
00093 {
00094 #define Ttab(x) *(word32 *)((byte *)m_T.begin()+x)
00095
00096 a = m_outsideCounter ^ m_R[4*m_insideCounter];
00097 b = rotrFixed(m_outsideCounter, 8U) ^ m_R[4*m_insideCounter+1];
00098 c = rotrFixed(m_outsideCounter, 16U) ^ m_R[4*m_insideCounter+2];
00099 d = rotrFixed(m_outsideCounter, 24U) ^ m_R[4*m_insideCounter+3];
00100
00101 for (unsigned int j=0; j<2; j++)
00102 {
00103 p = a & 0x7fc;
00104 b += Ttab(p);
00105 a = rotrFixed(a, 9U);
00106
00107 p = b & 0x7fc;
00108 c += Ttab(p);
00109 b = rotrFixed(b, 9U);
00110
00111 p = c & 0x7fc;
00112 d += Ttab(p);
00113 c = rotrFixed(c, 9U);
00114
00115 p = d & 0x7fc;
00116 a += Ttab(p);
00117 d = rotrFixed(d, 9U);
00118 }
00119
00120 n1 = d, n2 = b, n3 = a, n4 = c;
00121
00122 p = a & 0x7fc;
00123 b += Ttab(p);
00124 a = rotrFixed(a, 9U);
00125
00126 p = b & 0x7fc;
00127 c += Ttab(p);
00128 b = rotrFixed(b, 9U);
00129
00130 p = c & 0x7fc;
00131 d += Ttab(p);
00132 c = rotrFixed(c, 9U);
00133
00134 p = d & 0x7fc;
00135 a += Ttab(p);
00136 d = rotrFixed(d, 9U);
00137
00138
00139 for (unsigned int i=0; i<64; i++)
00140 {
00141 p = a & 0x7fc;
00142 a = rotrFixed(a, 9U);
00143 b += Ttab(p);
00144 b ^= a;
00145
00146 q = b & 0x7fc;
00147 b = rotrFixed(b, 9U);
00148 c ^= Ttab(q);
00149 c += b;
00150
00151 p = (p+c) & 0x7fc;
00152 c = rotrFixed(c, 9U);
00153 d += Ttab(p);
00154 d ^= c;
00155
00156 q = (q+d) & 0x7fc;
00157 d = rotrFixed(d, 9U);
00158 a ^= Ttab(q);
00159 a += d;
00160
00161 p = (p+a) & 0x7fc;
00162 b ^= Ttab(p);
00163 a = rotrFixed(a, 9U);
00164
00165 q = (q+b) & 0x7fc;
00166 c += Ttab(q);
00167 b = rotrFixed(b, 9U);
00168
00169 p = (p+c) & 0x7fc;
00170 d ^= Ttab(p);
00171 c = rotrFixed(c, 9U);
00172
00173 q = (q+d) & 0x7fc;
00174 d = rotrFixed(d, 9U);
00175 a += Ttab(q);
00176
00177 #define SEAL_OUTPUT(x) \
00178 CRYPTOPP_KEYSTREAM_OUTPUT_WORD(x, B::ToEnum(), 0, b + m_S[4*i+0]);\
00179 CRYPTOPP_KEYSTREAM_OUTPUT_WORD(x, B::ToEnum(), 1, c ^ m_S[4*i+1]);\
00180 CRYPTOPP_KEYSTREAM_OUTPUT_WORD(x, B::ToEnum(), 2, d + m_S[4*i+2]);\
00181 CRYPTOPP_KEYSTREAM_OUTPUT_WORD(x, B::ToEnum(), 3, a ^ m_S[4*i+3]);
00182
00183 CRYPTOPP_KEYSTREAM_OUTPUT_SWITCH(SEAL_OUTPUT, 4*4);
00184
00185 if (i & 1)
00186 {
00187 a += n3;
00188 b += n4;
00189 c ^= n3;
00190 d ^= n4;
00191 }
00192 else
00193 {
00194 a += n1;
00195 b += n2;
00196 c ^= n1;
00197 d ^= n2;
00198 }
00199 }
00200
00201 if (++m_insideCounter == m_iterationsPerCount)
00202 {
00203 ++m_outsideCounter;
00204 m_insideCounter = 0;
00205 }
00206 }
00207
00208 a = b = c = d = n1 = n2 = n3 = n4 = 0;
00209 p = q = 0;
00210 }
00211
00212 template class SEAL_Policy<BigEndian>;
00213 template class SEAL_Policy<LittleEndian>;
00214
00215 NAMESPACE_END
00216
00217 #endif