rtab[i] = strt ;

strt <<= 1 ;

if( strt&0x10000 ) strt A= 0x11011 ; }

/* Modified slightly to fit the callers needs. */ void encrypt(twy ctx *c, word32 *a)

char i ;

for( i=0 ; i<NMBR ; i++ ) {

a[0] A= c->k[0] A (c->ercon[i]<<16) ; a[1] A= c->k[1] ;

a[2] A= c->k[2] A c->ercon[i] ;

rho(a) ;

a[0] A= c->k[0] A (c->ercon[NMBR]<<16) ; a[1] A= c->k[1] ;

a[2] A= c->k[2] A c->ercon[NMBR] ;

theta(a) ;

/* Modified slightly to meet callers needs. */ void decrypt(twy ctx *c, word32 *a)

char i ; mu(a) ;

for( i=0 ; i<NMBR ; i++ ) {

a[0] A= c->ki[0] A (c->drcon[i]<<16) ; a[1] A= c->ki[1] ;

a[2] A= c->ki[2] A c->drcon[i] ;

rho(a) ;

a[0] A= c->ki[0] A (c->drcon[NMBR]<<16) ;

a[1] A= c->ki[1] ;

a[2] A= c->ki[2] A c->drcon[NMBR] ;

theta(a) ; mu(a) ;

void twy key(twy ctx *c, u4 *key){

c->ki[0] = c->k[0] = key[0]; c->ki[1] = c->k[1] = key[1]; c->ki[2] = c->k[2] = key[2];

theta(c->ki); mu(c->ki);

rndcon gen(STRT E,c->ercon); rndcon gen(STRT D,c->drcon);

/* Encrypt in ECB mode. */

void twy enc(twy ctx *c, u4 *data, int blkcnt){ int i; d = data;

for(i=0;i<blkcnt;i++) {

encrypt(c,d); d +=3;

/* Decrypt in ECB mode. */

void twy dec(twy ctx *c, u4 *data, int blkcnt){ u4 *d; int i;

d = data;

for(i=0;i<blkcnt;i++){ decrypt(c,d);

/* Scrub sensitive values from memory before deallocating. */ void twy destroy(twy ctx *c){ int i;

for(i=0;i<3;i++) c->k[i] = c->ki[i] = 0;

void printvec(char *chrs, word32 *d){

printf("%20s : %08lx %08lx %08lx \n",chrs,d[2],d[1],d[0]);

twy ctx gc;

word32 a[9],k[3];

/* Test vector 1. */

k[0]=k[1]=k[2]=0; a[0]=a[1]=a[2]=1;

twy key(&gc,k);

printf("**********\n"); printvec("KEY = ",k); printvec("PLAIN = ",a); encrypt(&gc,a); printvec("CIPHER = ",a);

/* Test vector 2. */

k[0]=6;k[1]=5;k[2]=4;

a[0]=3;a[1]=2;a[2]=1; twy key(&gc,k);

printf("**********\n");

printvec("KEY = ",k);

printvec("PLAIN = ",a); encrypt(&gc,a);

printvec("CIPHER = ",a);

/* Test vector 3. */

k[2]=0xbcdef012;k[1]=0x4 56789ab;k[0]=0xdef01234; a[2]=0x01234567;a[1]=0x9abcdef0;a[0]=0x23456789; twy key(&gc,k);

printf("**********\n"); printvec("KEY = ",k); printvec("PLAIN = ",a); encrypt(&gc,a); printvec("CIPHER = ",a);

/* Test vector 4. */

k[2]=0xcab920cd;k[1]=0xd614 4138;k[0]=0xd2f05b5e; a[2]=0xad21ecf7;a[1]=0x83ae9dc4;a[0]=0x4059c7 6e; twy key(&gc,k);

printf("**********\n");

printvec("KEY = ",k); printvec("PLAIN = ",a); encrypt(&gc,a);

printvec("CIPHER = ",a);

/* TEST VALUES

key: 00000000 00000000 00000000

plaintext : 00000001 00000001 00000001 ciphertext : ad21ecf7 83ae9dc4 4059c76e

key: 00000004 00000005 00000006

plaintext : 00000001 00000002 00000003 ciphertext : cab920cd d6144138 d2f05b5e

key: bcdef012 456789ab def01234

plaintext : 01234567 9abcdef0 23456789

ciphertext : 7cdb76b2 9cdddb6d 0aa55dbb

key: cab920cd d6144138 d2f05b5e

plaintext : ad21ecf7 83ae9dc4 4059c76e ciphertext : 15b155ed 6b13f17c 478ea871

/* Enc/dec test: */ for(i=0;i<9;i++) a[i]=i; twy enc(&gc,a,3);

for(i=0;i<9;i+=3) printf("Block %01d encrypts to %08lx %08lx %08lx\n",

i/3,a[i],a[i+1],a[i+2]);

twy dec(&gc,a,2); twy dec(&gc,a+6,1);

for(i=0;i<9;i+=3) printf("Block %01d decrypts to %08lx %08lx %08lx\n",

i/3,a[i],a[i+1],a[i+2]);