/* 128-bit key in k[0] .. k[3]. 64-bit data in v[0] .. v[1]. */
main (int artgc, char **argv, char **env) {
unsigned long v[2], k[4];
v[0] = 0x12345678; v[1] = 0x9abcdef0;
k[0] = 0x61626364; k[1] = 0x62636465;
k[2] = 0x63646566; k[3] = 0x64656667;
printf ("c_tea:\n");
printf (" key = 0x%x %x %x %x\n\n", k[0], k[1], k[2], k[3]);
printf (" v = 0x%x %x\n", v[0], v[1]);
tea_code (v, k);
printf (" coded = 0x%x %x\n", v[0], v[1]);
tea_decode (v, k);
printf ("decoded = 0x%x %x\n", v[0], v[1]);
}
encrypt () {
}
decrypt () {
}
tea_code(long* v, long* k) { /* long is 4 bytes. */
unsigned long v0=v[0], v1=v[1], k0=k[0], k1=k[1], k2=k[2], k3=k[3],
sum=0, delta=0x9e3779b9, n=32;
while (n-- > 0) {
sum += delta;
v0 += (v1<<4)+k0 ^ v1+sum ^ (v1>>5)+k1;
v1 += (v0<<4)+k2 ^ v0+sum ^ (v0>>5)+k3;
}
v[0]=v0; v[1]=v1;
}
tea_decode(long* v, long* k) {
unsigned long v0=v[0], v1=v[1], k0=k[0], k1=k[1], k2=k[2], k3=k[3],
n=32, sum, delta=0x9e3779b9;
sum=delta<<5;
while (n-- > 0) {
v1 -= (v0<<4)+k2 ^ v0+sum ^ (v0>>5)+k3;
v0 -= (v1<<4)+k0 ^ v1+sum ^ (v1>>5)+k1;
sum -= delta;
}
v[0]=v0; v[1]=v1;
}
