// blowfish.cpp - written and placed in the public domain by Wei Dai #include "pch.h" #include "blowfish.h" #include "misc.h" NAMESPACE_BEGIN(CryptoPP) void Blowfish::Base::UncheckedSetKey(const byte *key_string, unsigned int keylength, const NameValuePairs &) { AssertValidKeyLength(keylength); unsigned i, j=0, k; word32 data, dspace[2] = {0, 0}; memcpy(pbox, p_init, sizeof(p_init)); memcpy(sbox, s_init, sizeof(s_init)); // Xor key string into encryption key vector for (i=0 ; i<ROUNDS+2 ; ++i) { data = 0 ; for (k=0 ; k<4 ; ++k ) data = (data << 8) | key_string[j++ % keylength]; pbox[i] ^= data; } crypt_block(dspace, pbox); for (i=0; i<ROUNDS; i+=2) crypt_block(pbox+i, pbox+i+2); crypt_block(pbox+ROUNDS, sbox); for (i=0; i<4*256-2; i+=2) crypt_block(sbox+i, sbox+i+2); if (!IsForwardTransformation()) for (i=0; i<(ROUNDS+2)/2; i++) std::swap(pbox[i], pbox[ROUNDS+1-i]); } // this version is only used to make pbox and sbox void Blowfish::Base::crypt_block(const word32 in[2], word32 out[2]) const { word32 left = in[0]; word32 right = in[1]; const word32 *const s=sbox; const word32 *p=pbox; left ^= p[0]; for (unsigned i=0; i<ROUNDS/2; i++) { right ^= (((s[GETBYTE(left,3)] + s[256+GETBYTE(left,2)]) ^ s[2*256+GETBYTE(left,1)]) + s[3*256+GETBYTE(left,0)]) ^ p[2*i+1]; left ^= (((s[GETBYTE(right,3)] + s[256+GETBYTE(right,2)]) ^ s[2*256+GETBYTE(right,1)]) + s[3*256+GETBYTE(right,0)]) ^ p[2*i+2]; } right ^= p[ROUNDS+1]; out[0] = right; out[1] = left; } void Blowfish::Base::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const { typedef BlockGetAndPut<word32, BigEndian> Block; word32 left, right; Block::Get(inBlock)(left)(right); const word32 *const s=sbox; const word32 *p=pbox; left ^= p[0]; for (unsigned i=0; i<ROUNDS/2; i++) { right ^= (((s[GETBYTE(left,3)] + s[256+GETBYTE(left,2)]) ^ s[2*256+GETBYTE(left,1)]) + s[3*256+GETBYTE(left,0)]) ^ p[2*i+1]; left ^= (((s[GETBYTE(right,3)] + s[256+GETBYTE(right,2)]) ^ s[2*256+GETBYTE(right,1)]) + s[3*256+GETBYTE(right,0)]) ^ p[2*i+2]; } right ^= p[ROUNDS+1]; Block::Put(xorBlock, outBlock)(right)(left); } NAMESPACE_END