// wake.cpp - written and placed in the public domain by Wei Dai
#include "pch.h"
#include "wake.h"
NAMESPACE_BEGIN(CryptoPP)
void WAKE_TestInstantiations()
{
WAKE_OFB<>::Encryption x2;
WAKE_OFB<>::Decryption x4;
}
inline word32 WAKE_Base::M(word32 x, word32 y)
{
word32 w = x+y;
return (w>>8) ^ t[w & 0xff];
}
void WAKE_Base::GenKey(word32 k0, word32 k1, word32 k2, word32 k3)
{
// this code is mostly copied from David Wheeler's paper "A Bulk Data Encryption Algorithm"
signed int x, z, p;
// x and z were declared as "long" in Wheeler's paper, which is a signed type. I don't know if that was intentional, but it's too late to change it now. -- Wei 7/4/2010
CRYPTOPP_COMPILE_ASSERT(sizeof(x) == 4);
static int tt[10]= {
0x726a8f3b, // table
0xe69a3b5c,
0xd3c71fe5,
0xab3c73d2,
0x4d3a8eb3,
0x0396d6e8,
0x3d4c2f7a,
0x9ee27cf3, } ;
t[0] = k0;
t[1] = k1;
t[2] = k2;
t[3] = k3;
for (p=4 ; p<256 ; p++)
{
x=t[p-4]+t[p-1] ; // fill t
t[p]= (x>>3) ^ tt[x&7] ;
}
for (p=0 ; p<23 ; p++)
t[p]+=t[p+89] ; // mix first entries
x=t[33] ; z=t[59] | 0x01000001 ;
z=z&0xff7fffff ;
for (p=0 ; p<256 ; p++) { //change top byte to
x=(x&0xff7fffff)+z ; // a permutation etc
t[p]=(t[p] & 0x00ffffff) ^ x ; }
t[256]=t[0] ;
byte y=byte(x);
for (p=0 ; p<256 ; p++) { // further change perm.
t[p]=t[y=byte(t[p^y]^y)] ; // and other digits
t[y]=t[p+1] ; }
}
template <class B>
void WAKE_Policy<B>::CipherSetKey(const NameValuePairs ¶ms, const byte *key, size_t length)
{
word32 k0, k1, k2, k3;
BlockGetAndPut<word32, BigEndian>::Get(key)(r3)(r4)(r5)(r6)(k0)(k1)(k2)(k3);
GenKey(k0, k1, k2, k3);
}
// OFB
template <class B>
void WAKE_Policy<B>::OperateKeystream(KeystreamOperation operation, byte *output, const byte *input, size_t iterationCount)
{
#define WAKE_OUTPUT(x)\
while (iterationCount--)\
{\
CRYPTOPP_KEYSTREAM_OUTPUT_WORD(x, B::ToEnum(), 0, r6);\
r3 = M(r3, r6);\
r4 = M(r4, r3);\
r5 = M(r5, r4);\
r6 = M(r6, r5);\
output += 4;\
if (!(x & INPUT_NULL))\
input += 4;\
}
typedef word32 WordType;
CRYPTOPP_KEYSTREAM_OUTPUT_SWITCH(WAKE_OUTPUT, 0);
}
/*
template <class B>
void WAKE_ROFB_Policy<B>::Iterate(KeystreamOperation operation, byte *output, const byte *input, unsigned int iterationCount)
{
KeystreamOutput<B> keystreamOperation(operation, output, input);
while (iterationCount--)
{
keystreamOperation(r6);
r3 = M(r3, r6);
r4 = M(r4, r3);
r5 = M(r5, r4);
r6 = M(r6, r5);
}
}
*/
template class WAKE_Policy<BigEndian>;
template class WAKE_Policy<LittleEndian>;
//template class WAKE_ROFB_Policy<BigEndian>;
//template class WAKE_ROFB_Policy<LittleEndian>;
NAMESPACE_END
