Alloy Computer Products BWS-136 user manual Unsigned long

although impractical.

************************************************/

//#include "xtea.h"

void encipher(unsigned long *const v,unsigned long *const w, const unsigned long *const k)

{

register unsigned long y=v[0],z=v[1],sum=0,delta=0x9E3779B9,n=32; while(n-->0)

{y+= (z<<4 ^ z>>5) + z ^ sum + k[sum&3]; sum += delta;

z+= (y<<4 ^ y>>5) + y ^ sum + k[sum>>11 & 3];

}

w[0]=y; w[1]=z;

}

void decipher(unsigned long *const v,unsigned long *const w, const unsigned long *const k)

{

register	unsigned long	y=v[0],z=v[1],sum=0xC6EF3720,
		delta=0x9E3779B9,n=32;
/* sum =	delta<<5, in general sum = delta * n */
while(n-->0)
{

z-= (y<<4 ^ y>>5) + y ^ sum + k[sum>>11 & 3]; sum -= delta;

y-= (z<<4 ^ z>>5) + z ^ sum + k[sum&3];

}
w[0]=y; w[1]=z;
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}

2.The TEA.H

#ifndef __XTEA_H__ #define __XTEA_H__

void encipher(unsigned long *const v,unsigned long *const w, const unsigned long *const k);

void decipher(unsigned long *const v,unsigned long *const w, const unsigned long *const k);

#endif

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