DESCrypter.cpp File Reference

#include <zeusbase/Security/DESCrypter.h>

Defines
#define	DO_PERMUTATION(a, temp, b, offset, mask)
#define	INITIAL_PERMUTATION(left, temp, right)
#define	FINAL_PERMUTATION(left, temp, right)
#define	DES_ROUND(from, to, work, subkey)
#define	READ_64BIT_DATA(data, left, right)
#define	WRITE_64BIT_DATA(data, left, right)

---

Define Documentation

#define DES_ROUND	(		from,
			to,
			work,
			subkey
	)

Value:

work = from ^ *subkey++;               \
    to ^= sbox8[  work      & 0x3f ];      \
    to ^= sbox6[ (work>>8)  & 0x3f ];      \
    to ^= sbox4[ (work>>16) & 0x3f ];      \
    to ^= sbox2[ (work>>24) & 0x3f ];      \
    work = ((from << 28) | (from >> 4)) ^ *subkey++;  \
    to ^= sbox7[  work      & 0x3f ];      \
    to ^= sbox5[ (work>>8)  & 0x3f ];      \
    to ^= sbox3[ (work>>16) & 0x3f ];      \
    to ^= sbox1[ (work>>24) & 0x3f ];

#define DO_PERMUTATION	(		a,
			temp,
			b,
			offset,
			mask
	)

Value:

temp = ((a>>offset) ^ b) & mask;              \
    b ^= temp;                                    \
    a ^= temp<<offset;

#define FINAL_PERMUTATION	(		left,
			temp,
			right
	)

Value:

left  =  (left << 31) | (left >> 1);              \
    temp  =  (left ^ right) & 0xaaaaaaaa;             \
    left  ^= temp;                                    \
    right ^= temp;                                    \
    right  =  (right << 31) | (right >> 1);           \
    DO_PERMUTATION(right, temp, left, 8, 0x00ff00ff)  \
    DO_PERMUTATION(right, temp, left, 2, 0x33333333)  \
    DO_PERMUTATION(left, temp, right, 16, 0x0000ffff) \
    DO_PERMUTATION(left, temp, right, 4, 0x0f0f0f0f)

#define INITIAL_PERMUTATION	(		left,
			temp,
			right
	)

Value:

DO_PERMUTATION(left, temp, right, 4, 0x0f0f0f0f)   \
    DO_PERMUTATION(left, temp, right, 16, 0x0000ffff)  \
    DO_PERMUTATION(right, temp, left, 2, 0x33333333)   \
    DO_PERMUTATION(right, temp, left, 8, 0x00ff00ff)   \
    right =  (right << 1) | (right >> 31);             \
    temp  =  (left ^ right) & 0xaaaaaaaa;              \
    right ^= temp;                                     \
    left  ^= temp;                                     \
    left  =  (left << 1) | (left >> 31);

#define READ_64BIT_DATA	(		data,
			left,
			right
	)

Value:

left  = (data[0] << 24) | (data[1] << 16) | (data[2] << 8) | data[3];  \
    right = (data[4] << 24) | (data[5] << 16) | (data[6] << 8) | data[7];

#define WRITE_64BIT_DATA	(		data,
			left,
			right
	)

Value:

data[0] = (Uint8)((left  >> 24) & 0xff); data[1] = (Uint8)((left >> 16) & 0xff);  \
    data[2] = (Uint8)((left  >>  8) & 0xff); data[3] = (Uint8)(left &0xff);           \
    data[4] = (Uint8)((right >> 24) & 0xff); data[5] = (Uint8)((right >> 16) & 0xff); \
    data[6] = (Uint8)((right >>  8) & 0xff); data[7] = (Uint8)(right & 0xff);