des.cc

COPE the first practical network coding scheme which is developped on click

/* for C bits (numbered as per FIPS 46) 7 8 10 11 12 13 */
 {0x00000000,0x02000000,0x00002000,0x02002000,
  0x00200000,0x02200000,0x00202000,0x02202000,
  0x00000004,0x02000004,0x00002004,0x02002004,
  0x00200004,0x02200004,0x00202004,0x02202004,
  0x00000400,0x02000400,0x00002400,0x02002400,
  0x00200400,0x02200400,0x00202400,0x02202400,
  0x00000404,0x02000404,0x00002404,0x02002404,
  0x00200404,0x02200404,0x00202404,0x02202404,
  0x10000000,0x12000000,0x10002000,0x12002000,
  0x10200000,0x12200000,0x10202000,0x12202000,
  0x10000004,0x12000004,0x10002004,0x12002004,
  0x10200004,0x12200004,0x10202004,0x12202004,
  0x10000400,0x12000400,0x10002400,0x12002400,
  0x10200400,0x12200400,0x10202400,0x12202400,
  0x10000404,0x12000404,0x10002404,0x12002404,
  0x10200404,0x12200404,0x10202404,0x12202404},
/* for C bits (numbered as per FIPS 46) 14 15 16 17 19 20 */
 {0x00000000,0x00000001,0x00040000,0x00040001,
  0x01000000,0x01000001,0x01040000,0x01040001,
  0x00000002,0x00000003,0x00040002,0x00040003,
  0x01000002,0x01000003,0x01040002,0x01040003,
  0x00000200,0x00000201,0x00040200,0x00040201,
  0x01000200,0x01000201,0x01040200,0x01040201,
  0x00000202,0x00000203,0x00040202,0x00040203,
  0x01000202,0x01000203,0x01040202,0x01040203,
  0x08000000,0x08000001,0x08040000,0x08040001,
  0x09000000,0x09000001,0x09040000,0x09040001,
  0x08000002,0x08000003,0x08040002,0x08040003,
  0x09000002,0x09000003,0x09040002,0x09040003,
  0x08000200,0x08000201,0x08040200,0x08040201,
  0x09000200,0x09000201,0x09040200,0x09040201,
  0x08000202,0x08000203,0x08040202,0x08040203,
  0x09000202,0x09000203,0x09040202,0x09040203},
/* for C bits (numbered as per FIPS 46) 21 23 24 26 27 28 */
 {0x00000000,0x00100000,0x00000100,0x00100100,
  0x00000008,0x00100008,0x00000108,0x00100108,
  0x00001000,0x00101000,0x00001100,0x00101100,
  0x00001008,0x00101008,0x00001108,0x00101108,
  0x04000000,0x04100000,0x04000100,0x04100100,
  0x04000008,0x04100008,0x04000108,0x04100108,
  0x04001000,0x04101000,0x04001100,0x04101100,
  0x04001008,0x04101008,0x04001108,0x04101108,
  0x00020000,0x00120000,0x00020100,0x00120100,
  0x00020008,0x00120008,0x00020108,0x00120108,
  0x00021000,0x00121000,0x00021100,0x00121100,
  0x00021008,0x00121008,0x00021108,0x00121108,
  0x04020000,0x04120000,0x04020100,0x04120100,
  0x04020008,0x04120008,0x04020108,0x04120108,
  0x04021000,0x04121000,0x04021100,0x04121100,
  0x04021008,0x04121008,0x04021108,0x04121108},
/* for D bits (numbered as per FIPS 46) 1 2 3 4 5 6 */
 {0x00000000,0x10000000,0x00010000,0x10010000,
  0x00000004,0x10000004,0x00010004,0x10010004,
  0x20000000,0x30000000,0x20010000,0x30010000,
  0x20000004,0x30000004,0x20010004,0x30010004,
  0x00100000,0x10100000,0x00110000,0x10110000,
  0x00100004,0x10100004,0x00110004,0x10110004,
  0x20100000,0x30100000,0x20110000,0x30110000,
  0x20100004,0x30100004,0x20110004,0x30110004,
  0x00001000,0x10001000,0x00011000,0x10011000,
  0x00001004,0x10001004,0x00011004,0x10011004,
  0x20001000,0x30001000,0x20011000,0x30011000,
  0x20001004,0x30001004,0x20011004,0x30011004,
  0x00101000,0x10101000,0x00111000,0x10111000,
  0x00101004,0x10101004,0x00111004,0x10111004,
  0x20101000,0x30101000,0x20111000,0x30111000,
  0x20101004,0x30101004,0x20111004,0x30111004},
/* for D bits (numbered as per FIPS 46) 8 9 11 12 13 14 */
 {0x00000000,0x08000000,0x00000008,0x08000008,
  0x00000400,0x08000400,0x00000408,0x08000408,
  0x00020000,0x08020000,0x00020008,0x08020008,
  0x00020400,0x08020400,0x00020408,0x08020408,
  0x00000001,0x08000001,0x00000009,0x08000009,
  0x00000401,0x08000401,0x00000409,0x08000409,
  0x00020001,0x08020001,0x00020009,0x08020009,
  0x00020401,0x08020401,0x00020409,0x08020409,
  0x02000000,0x0A000000,0x02000008,0x0A000008,
  0x02000400,0x0A000400,0x02000408,0x0A000408,
  0x02020000,0x0A020000,0x02020008,0x0A020008,
  0x02020400,0x0A020400,0x02020408,0x0A020408,
  0x02000001,0x0A000001,0x02000009,0x0A000009,
  0x02000401,0x0A000401,0x02000409,0x0A000409,
  0x02020001,0x0A020001,0x02020009,0x0A020009,
  0x02020401,0x0A020401,0x02020409,0x0A020409},
/* for D bits (numbered as per FIPS 46) 16 17 18 19 20 21 */
 {0x00000000,0x00000100,0x00080000,0x00080100,
  0x01000000,0x01000100,0x01080000,0x01080100,
  0x00000010,0x00000110,0x00080010,0x00080110,
  0x01000010,0x01000110,0x01080010,0x01080110,
  0x00200000,0x00200100,0x00280000,0x00280100,
  0x01200000,0x01200100,0x01280000,0x01280100,
  0x00200010,0x00200110,0x00280010,0x00280110,
  0x01200010,0x01200110,0x01280010,0x01280110,
  0x00000200,0x00000300,0x00080200,0x00080300,
  0x01000200,0x01000300,0x01080200,0x01080300,
  0x00000210,0x00000310,0x00080210,0x00080310,
  0x01000210,0x01000310,0x01080210,0x01080310,
  0x00200200,0x00200300,0x00280200,0x00280300,
  0x01200200,0x01200300,0x01280200,0x01280300,
  0x00200210,0x00200310,0x00280210,0x00280310,
  0x01200210,0x01200310,0x01280210,0x01280310},
/* for D bits (numbered as per FIPS 46) 22 23 24 25 27 28 */
 {0x00000000,0x04000000,0x00040000,0x04040000,
  0x00000002,0x04000002,0x00040002,0x04040002,
  0x00002000,0x04002000,0x00042000,0x04042000,
  0x00002002,0x04002002,0x00042002,0x04042002,
  0x00000020,0x04000020,0x00040020,0x04040020,
  0x00000022,0x04000022,0x00040022,0x04040022,
  0x00002020,0x04002020,0x00042020,0x04042020,
  0x00002022,0x04002022,0x00042022,0x04042022,
  0x00000800,0x04000800,0x00040800,0x04040800,
  0x00000802,0x04000802,0x00040802,0x04040802,
  0x00002800,0x04002800,0x00042800,0x04042800,
  0x00002802,0x04002802,0x00042802,0x04042802,
  0x00000820,0x04000820,0x00040820,0x04040820,
  0x00000822,0x04000822,0x00040822,0x04040822,
  0x00002820,0x04002820,0x00042820,0x04042820,
  0x00002822,0x04002822,0x00042822,0x04042822}
};

/* from ecb_encrypt.c */

#define PERM_OP(a,b,t,n,m) ((t)=((((a)>>(n))^(b))&(m)),\
	(b)^=(t),\
	(a)=((a)^((t)<<(n))))

#define HPERM_OP(a,t,n,m) ((t)=((((a)<<(16-(n)))^(a))&(m)),\
	(a)=(a)^(t)^(t>>(16-(n))))

static char shifts2[16]={0,0,1,1,1,1,1,1,0,1,1,1,1,1,1,0};


#define D_ENCRYPT(L,R,S)	\
	u=(R^s[S  ]); \
	t=R^s[S+1]; \
	t=((t>>4)+(t<<28)); \
	L^=	des_SPtrans[1][(t    )&0x3f]| \
		des_SPtrans[3][(t>> 8)&0x3f]| \
		des_SPtrans[5][(t>>16)&0x3f]| \
		des_SPtrans[7][(t>>24)&0x3f]| \
		des_SPtrans[0][(u    )&0x3f]| \
		des_SPtrans[2][(u>> 8)&0x3f]| \
		des_SPtrans[4][(u>>16)&0x3f]| \
		des_SPtrans[6][(u>>24)&0x3f];


void
Des::des_encrypt(unsigned long *input,unsigned long *output,
		 des_key_schedule ks,int encrypt)
{
  register unsigned long l,r,t,u;
  register int i;
  register unsigned long *s;
  
  l=input[0];
  r=input[1];
  
  /* do IP */
  PERM_OP(r,l,t, 4,0x0f0f0f0f);
  PERM_OP(l,r,t,16,0x0000ffff);
  PERM_OP(r,l,t, 2,0x33333333);
  PERM_OP(l,r,t, 8,0x00ff00ff);
  PERM_OP(r,l,t, 1,0x55555555);
  /* r and l are reversed - remember that :-) - fix
   * it in the next step */
  
  /* Things have been modified so that the initial rotate is
   * done outside the loop.  This required the 
   * des_SPtrans values in sp.h to be rotated 1 bit to the right.
   * One perl script later and things have a 5% speed up on a sparc2.
   * Thanks to Richard Outerbridge <[e-mail]>
   * for pointing this out. */
  t=(r<<1)|(r>>31);
  r=(l<<1)|(l>>31); 
  l=t;
  
  /* clear the top bits on machines with 8byte longs */
  l&=0xffffffff;
  r&=0xffffffff;
  
  s=(unsigned long *)ks;
  /* I don't know if it is worth the effort of loop unrolling the
   * inner loop */
  if (encrypt)
    {
      for (i=0; i<32; i+=4)
	{
	  D_ENCRYPT(l,r,i+0); /*  1 */
	  D_ENCRYPT(r,l,i+2); /*  2 */
	}
    }
  else
    {
      for (i=30; i>0; i-=4)
	{
	  D_ENCRYPT(l,r,i-0); /* 16 */
	  D_ENCRYPT(r,l,i-2); /* 15 */
	}
    }
  l=(l>>1)|(l<<31);
  r=(r>>1)|(r<<31);
  /* clear the top bits on machines with 8byte longs */
  l&=0xffffffff;
  r&=0xffffffff;
  
  /* swap l and r
   * we will not do the swap so just remember they are
   * reversed for the rest of the subroutine
   * luckily FP fixes this problem :-) */
  
  PERM_OP(r,l,t, 1,0x55555555);
  PERM_OP(l,r,t, 8,0x00ff00ff);
  PERM_OP(r,l,t, 2,0x33333333);
  PERM_OP(l,r,t,16,0x0000ffff);
  PERM_OP(r,l,t, 4,0x0f0f0f0f);

  output[0]=l;
  output[1]=r;
}

int
Des::des_ecb_encrypt(des_cblock *input,des_cblock *output,
		     des_key_schedule ks, int encrypt)
	{
	register unsigned long l0,l1;
	register unsigned char *in,*out;
	unsigned long ll[2];

	in=(unsigned char *)input;
	out=(unsigned char *)output;
	c2l(in,l0);
	c2l(in,l1);
	ll[0]=l0;
	ll[1]=l1;
	des_encrypt(ll,ll,ks,encrypt);
	l0=ll[0];
	l1=ll[1];
	l2c(l0,out);
	l2c(l1,out);
	return(0);
	}

/* from set_key.c */

void
Des::des_set_key(des_cblock *key,des_key_schedule schedule)
	{
	register unsigned long c,d,t,s;
	register unsigned char *in;
	register unsigned long *k;
	register int i;

	k=(unsigned long *)schedule;
	in=(unsigned char *)key;

	c2l(in,c);
	c2l(in,d);

	/* I now do it in 47 simple operations :-)
	 * Thanks to John Fletcher ([e-mail])
	 * for the inspiration. :-) */
	PERM_OP (d,c,t,4,0x0f0f0f0f);
	HPERM_OP(c,t,-2,0xcccc0000);
	HPERM_OP(d,t,-2,0xcccc0000);
	PERM_OP (d,c,t,1,0x55555555);
	PERM_OP (c,d,t,8,0x00ff00ff);
	PERM_OP (d,c,t,1,0x55555555);
	d=	(((d&0x000000ff)<<16)| (d&0x0000ff00)     |
		 ((d&0x00ff0000)>>16)|((c&0xf0000000)>>4));
	c&=0x0fffffff;

	for (i=0; i<ITERATIONS; i++)
		{
		if (shifts2[i])
			{ c=((c>>2)|(c<<26)); d=((d>>2)|(d<<26)); }
		else
			{ c=((c>>1)|(c<<27)); d=((d>>1)|(d<<27)); }
		c&=0x0fffffff;
		d&=0x0fffffff;
		/* could be a few less shifts but I am to lazy at this
		 * point in time to investigate */
		s=	des_skb[0][ (c    )&0x3f                ]|
			des_skb[1][((c>> 6)&0x03)|((c>> 7)&0x3c)]|
			des_skb[2][((c>>13)&0x0f)|((c>>14)&0x30)]|
			des_skb[3][((c>>20)&0x01)|((c>>21)&0x06) |
						  ((c>>22)&0x38)];
		t=	des_skb[4][ (d    )&0x3f                ]|
			des_skb[5][((d>> 7)&0x03)|((d>> 8)&0x3c)]|
			des_skb[6][ (d>>15)&0x3f                ]|
			des_skb[7][((d>>21)&0x0f)|((d>>22)&0x30)];

		/* table contained 0213 4657 */
		*(k++)=((t<<16)|(s&0x0000ffff))&0xffffffff;
		s=     ((s>>16)|(t&0xffff0000));
		
		s=(s<<4)|(s>>28);
		*(k++)=s&0xffffffff;
		}
	}

CLICK_ENDDECLS
EXPORT_ELEMENT(Des)