#include <stdint.h>
#include <string.h>
#include "trivium.h"
+#include <avr/pgmspace.h>
-#define S(i) ((((*ctx)[(i)/8])>>((i)%8))&1)
+#define G(i) ((((*ctx)[(i)/8])>>(((i)%8)))&1)
+#define S(i,v) ((*ctx)[(i)/8] = (((*ctx)[(i)/8]) & (uint8_t)~(1<<((i)%8))) | ((v)<<((i)%8)))
uint8_t trivium_enc(trivium_ctx_t* ctx){
uint8_t t1,t2,t3,z;
- t1 = S(65) ^ S(92);
- t2 = S(161) ^ S(176);
- t3 = S(242) ^ S(287);
+ t1 = G(65) ^ G(92);
+ t2 = G(161) ^ G(176);
+ t3 = G(242) ^ G(287);
z = t1^t2^t3;
- t1 ^= (S(90) & S(91)) ^ S(170);
- t2 ^= (S(174) & S(175)) ^ S(263);
- t3 ^= (S(285) & S(286)) ^ S(68);
+ t1 ^= (G(90) & G(91)) ^ G(170);
+ t2 ^= (G(174) & G(175)) ^ G(263);
+ t3 ^= (G(285) & G(286)) ^ G(68);
/* shift whole state and insert ts later */
uint8_t i,c1=0,c2;
c1=c2;
}
/* insert ts */
- (*ctx)[0] = (((*ctx)[0])&0xFE)| t3; /* s0*/
- (*ctx)[93/8] = (((*ctx)[93/8])& (~(1<<(93%8)))) | (t1<<(93%8)); /* s93 */
- (*ctx)[177/8] = (((*ctx)[177/8])& (~(1<<(177%8)))) | (t2<<(177%8));/* s177 */
+ S(0, t3);
+ S(93, t1);
+ S(177, t2);
- return z;
+ return z?0x080:0x00;
+}
+
+uint8_t trivium_getbyte(trivium_ctx_t *ctx){
+ uint8_t r=0, i=0;
+ do{
+ r>>=1;
+ r |= trivium_enc(ctx);
+ }while(++i<8);
+ return r;
}
#define KEYSIZE_B ((keysize_b+7)/8)
#define IVSIZE_B ((ivsize_b +7)/8)
-void trivium_init(const void* key, uint8_t keysize_b,
- const void* iv, uint8_t ivsize_b,
+static const uint8_t rev_table[16] PROGMEM = {
+ 0x00, 0x08, 0x04, 0x0C, /* 0000 1000 0100 1100 */
+ 0x02, 0x0A, 0x06, 0x0E, /* 0010 1010 0110 1110 */
+ 0x01, 0x09, 0x05, 0x0D, /* 0001 1001 0101 1101 */
+ 0x03, 0x0B, 0x07, 0x0F /* 0011 1011 0111 1111 */
+};
+
+void trivium_init(const void* key, uint16_t keysize_b,
+ const void* iv, uint16_t ivsize_b,
trivium_ctx_t* ctx){
uint16_t i;
- uint8_t c1=0,c2;
-
+ uint8_t c1,c2;
+ uint8_t t1,t2;
memset((*ctx)+KEYSIZE_B, 0, 35-KEYSIZE_B);
- memcpy((*ctx), key, KEYSIZE_B);
- memcpy((*ctx)+12, iv, IVSIZE_B); /* iv0 is at s96, must shift to s93 */
-
+ c2=0;
+ c1=KEYSIZE_B;
+ do{
+ t1 = ((uint8_t*)key)[--c1];
+ t2 = (pgm_read_byte(&(rev_table[t1&0x0f]))<<4)|(pgm_read_byte(&(rev_table[t1>>4])));
+ (*ctx)[c2++] = t2;
+ }while(c1!=0);
+
+ c2=12;
+ c1=IVSIZE_B;
+ do{
+ t1 = ((uint8_t*)iv)[--c1];
+ t2 = (pgm_read_byte(&(rev_table[t1&0x0f]))<<4)|(pgm_read_byte(&(rev_table[t1>>4])));
+ (*ctx)[c2++] = t2;
+ }while(c1!=0);
+
for(i=12+IVSIZE_B; i>10; --i){
c2=(((*ctx)[i])<<5);
(*ctx)[i] = (((*ctx)[i])>>3)|c1;
c1=c2;
}
- (*ctx)[35]=0xE0;
+
+ (*ctx)[35] = 0xE0;
for(i=0; i<4*288; ++i){
trivium_enc(ctx);