Method ProcessBlock

src/cryptlib/des.cpp:314–364

Encrypt or decrypt a block of data in ECB mode

// Encrypt or decrypt a block of data in ECB mode
void DES::ProcessBlock(const byte *inBlock, byte * outBlock)
{
    word32 l,r,work;

#ifdef WORDS_BIGENDIAN
    l = *(word32 *)inBlock;
    r = *(word32 *)(inBlock+4);
#else
    l = byteReverse(*(word32 *)inBlock);
    r = byteReverse(*(word32 *)(inBlock+4));
#endif

    IPERM(l,r);

    const word32 *kptr=k;

    for (unsigned i=0; i<8; i++)
    {
        work = rotr(r, 4U) ^ kptr[4*i+0];
        l ^= Spbox[6][(work) & 0x3f]
          ^  Spbox[4][(work >> 8) & 0x3f]
          ^  Spbox[2][(work >> 16) & 0x3f]
          ^  Spbox[0][(work >> 24) & 0x3f];
        work = r ^ kptr[4*i+1];
        l ^= Spbox[7][(work) & 0x3f]
          ^  Spbox[5][(work >> 8) & 0x3f]
          ^  Spbox[3][(work >> 16) & 0x3f]
          ^  Spbox[1][(work >> 24) & 0x3f];

        work = rotr(l, 4U) ^ kptr[4*i+2];
        r ^= Spbox[6][(work) & 0x3f]
          ^  Spbox[4][(work >> 8) & 0x3f]
          ^  Spbox[2][(work >> 16) & 0x3f]
          ^  Spbox[0][(work >> 24) & 0x3f];
        work = l ^ kptr[4*i+3];
        r ^= Spbox[7][(work) & 0x3f]
          ^  Spbox[5][(work >> 8) & 0x3f]
          ^  Spbox[3][(work >> 16) & 0x3f]
          ^  Spbox[1][(work >> 24) & 0x3f];
    }

    FPERM(l,r);

#ifdef WORDS_BIGENDIAN
    *(word32 *)outBlock = r;
    *(word32 *)(outBlock+4) = l;
#else
    *(word32 *)outBlock = byteReverse(r);
    *(word32 *)(outBlock+4) = byteReverse(l);
#endif
}

void DES_EDE_Encryption::ProcessBlock(byte *inoutBlock)
{