*/
+#define STRING2(x) #x
+#define STRING(x) STRING2(x)
+#define STR_LINE STRING(__LINE__)
+
#include "bigint.h"
#include <string.h>
-
-#include "bigint_io.h"
+/*
#include "cli.h"
-
+#include "bigint_io.h"
+*/
#ifndef MAX
#define MAX(a,b) (((a)>(b))?(a):(b))
#endif
/******************************************************************************/
void bigint_copy(bigint_t* dest, const bigint_t* src){
- memcpy(dest->wordv, src->wordv, src->length_B);
dest->length_B = src->length_B;
dest->info = src->info;
+ memcpy(dest->wordv, src->wordv, src->length_B);
}
/******************************************************************************/
/* this should be implemented in assembly */
-/*
void bigint_add_u(bigint_t* dest, const bigint_t* a, const bigint_t* b){
uint16_t t=0, i;
if(a->length_B < b->length_B){
dest->length_B = i;
bigint_adjust(dest);
}
-*/
+
/******************************************************************************/
/* this should be implemented in assembly */
/* using the Karatsuba-Algorithm */
/* x*y = (xh*yh)*b**2n + ((xh+xl)*(yh+yl) - xh*yh - xl*yl)*b**n + yh*yl */
void bigint_mul_u(bigint_t* dest, const bigint_t* a, const bigint_t* b){
+ if(a->length_B==0 || b->length_B==0){
+ bigint_set_zero(dest);
+ return;
+ }
if(dest==a || dest==b){
bigint_t d;
uint8_t d_b[a->length_B+b->length_B];
bigint_copy(dest, &d);
return;
}
- if(a->length_B==0 || b->length_B==0){
- bigint_set_zero(dest);
- return;
- }
if(a->length_B==1 || b->length_B==1){
if(a->length_B!=1){
XCHG_PTR(a,b);
int16_t t;
if(a->length_B < b->length_B+byteshift){
- cli_putstr_P(PSTR("\r\nERROR: bigint_sub_u_bitscale result negative"));
bigint_set_zero(a);
return;
}
}
while(borrow){
if(i+1 > a->length_B){
- cli_putstr_P(PSTR("\r\nERROR: bigint_sub_u_bitscale result negative (2) shift="));
- cli_hexdump_rev(&bitscale, 2);
bigint_set_zero(a);
return;
}
/******************************************************************************/
void bigint_reduce(bigint_t* a, const bigint_t* r){
+// bigint_adjust(r);
uint8_t rfbs = GET_FBS(r);
-/*
- cli_putstr_P(PSTR("\r\nreduce "));
- bigint_print_hex(a);
- cli_putstr_P(PSTR(" % "));
- bigint_print_hex(r);
- cli_putstr_P(PSTR("\r\n"));
-*/
- if(r->length_B==0){
+ if(r->length_B==0 || a->length_B==0){
return;
}
while(a->length_B > r->length_B){
bigint_sub_u_bitscale(a, r, (a->length_B-r->length_B)*8+GET_FBS(a)-rfbs-1);
}
-
while((GET_FBS(a) > rfbs+1) && (a->length_B == r->length_B)){
bigint_sub_u_bitscale(a, r, GET_FBS(a)-rfbs-1);
}
-
while(bigint_cmp_u(a,r)>=0){
bigint_sub_u(a,a,r);
}
- bigint_adjust(a);
}
/******************************************************************************/
/* calculate dest = a**exp % r */
/* using square&multiply */
void bigint_expmod_u(bigint_t* dest, const bigint_t* a, const bigint_t* exp, const bigint_t* r){
- bigint_t tmp, tmp2, x;
- uint8_t x_b[MAX(r->length_B, a->length_B)], tmp_b[r->length_B*2], tmp2_b[r->length_B*2];
- int16_t i;
- uint8_t j;
- x.wordv = x_b;
- tmp.wordv = tmp_b;
- tmp2.wordv = tmp2_b;
- bigint_copy(&x, a);
- bigint_reduce(&x, r);
- bigint_copy(&tmp, &x);
- if(a->length_B==0 || exp->length_B==0 || r->length_B==0){
+ if(a->length_B==0 || r->length_B==0){
return;
}
- i=exp->length_B-1;
- if(exp->wordv[i]!=1){
- for(j=1<<(GET_FBS(exp)-1); j>0; j>>=1){
- // cli_putc('Q');
- bigint_square(&tmp2, &tmp);
- bigint_reduce(&tmp2, r);
- if(exp->wordv[i]&j){
- // cli_putc('M');
- bigint_mul_u(&tmp, &tmp2, &x);
- bigint_reduce(&tmp, r);
- }else{
- bigint_copy(&tmp, &tmp2);
+
+ bigint_t res, base;
+ uint8_t base_b[MAX(a->length_B,r->length_B*2)], res_b[r->length_B*2];
+ uint16_t i;
+ uint8_t j, t;
+ res.wordv = res_b;
+ base.wordv = base_b;
+ bigint_copy(&base, a);
+ bigint_reduce(&base, r);
+ res.wordv[0]=1;
+ res.length_B=1;
+ res.info = 0;
+ bigint_adjust(&res);
+ for(i=0; i+1<exp->length_B; ++i){
+ t=exp->wordv[i];
+ for(j=0; j<8; ++j){
+ if(t&1){
+ bigint_mul_u(&res, &res, &base);
+ bigint_reduce(&res, r);
}
+ bigint_square(&base, &base);
+ bigint_reduce(&base, r);
+ t>>=1;
}
}
- for(--i; i>=0; --i){
- for(j=0x80; j>0; j>>=1){
-// cli_putc('q');
- bigint_square(&tmp2, &tmp);
- bigint_reduce(&tmp2, r);
- if(exp->wordv[i]&j){
-// cli_putc('m');
- bigint_mul_u(&tmp, &tmp2, &x);
- bigint_reduce(&tmp, r);
- }else{
- bigint_copy(&tmp, &tmp2);
- }
+ t=exp->wordv[i];
+ while(t){
+ if(t&1){
+ bigint_mul_u(&res, &res, &base);
+ bigint_reduce(&res, r);
}
+ bigint_square(&base, &base);
+ bigint_reduce(&base, r);
+ t>>=1;
}
-// cli_putstr_P(PSTR("\r\n"));
- bigint_copy(dest, &tmp);
+ SET_POS(&res);
+ bigint_copy(dest, &res);
}
-#define DEBUG 0
+
/******************************************************************************/
/* gcd <-- gcd(x,y) a*x+b*y=gcd */
void bigint_gcdext(bigint_t* gcd, bigint_t* a, bigint_t* b, const bigint_t* x, const bigint_t* y){
for(i=0; (x_.wordv[0]&(1<<i))==0 && (y_.wordv[0]&(1<<i))==0; ++i){
}
-#if DEBUG
- cli_putstr_P(PSTR("\r\nDBG: initshift = "));
- cli_hexdump_rev(&i, 2);
-#endif
bigint_adjust(&x_);
bigint_adjust(&y_);
if(i){
bigint_shiftleft(&g, i);
-#if DEBUG
- cli_putstr_P(PSTR("\r\nDBG: initshift (2) = "));
- cli_hexdump_rev(&i, 2);
- cli_putstr_P(PSTR("\r\n x' = "));
- bigint_print_hex(&x_);
- cli_putstr_P(PSTR("\r\n y' = "));
- bigint_print_hex(&y_);
-#endif
- bigint_shiftright(&x_, i);
- bigint_shiftright(&y_, i);
-#if DEBUG
- cli_putstr_P(PSTR("\r\n x' = "));
- bigint_print_hex(&x_);
- cli_putstr_P(PSTR("\r\n y' = "));
- bigint_print_hex(&y_);
-#endif
+ bigint_shiftright(&x_, i);
+ bigint_shiftright(&y_, i);
}
u.wordv = u_b;
v.wordv = v_b;
bigint_set_zero(&b_);
bigint_set_zero(&c_);
do{
-#if DEBUG
- cli_putstr_P(PSTR("\r\n while u%2==0; u = "));
- bigint_print_hex(&u);
- cli_putstr_P(PSTR("\r\nDBG: (10) a = "));
- bigint_print_hex(&a_);
- cli_putstr_P(PSTR("\r\nDBG: (10) b = "));
- bigint_print_hex(&b_);
- cli_putstr_P(PSTR("\r\nDBG: (10) c = "));
- bigint_print_hex(&c_);
- cli_putstr_P(PSTR("\r\nDBG: (10) d = "));
- bigint_print_hex(&d_);
-#endif
while((u.wordv[0]&1)==0){
bigint_shiftright(&u, 1);
if((a_.wordv[0]&1) || (b_.wordv[0]&1)){
bigint_shiftright(&a_, 1);
bigint_shiftright(&b_, 1);
}
-#if DEBUG
- cli_putstr_P(PSTR("\r\n while v%2==0; v = "));
- bigint_print_hex(&v);
- cli_putstr_P(PSTR("\r\nDBG: (20) a = "));
- bigint_print_hex(&a_);
- cli_putstr_P(PSTR("\r\nDBG: (20) b = "));
- bigint_print_hex(&b_);
- cli_putstr_P(PSTR("\r\nDBG: (20) c = "));
- bigint_print_hex(&c_);
- cli_putstr_P(PSTR("\r\nDBG: (20) d = "));
- bigint_print_hex(&d_);
-#endif
while((v.wordv[0]&1)==0){
bigint_shiftright(&v, 1);
if((c_.wordv[0]&1) || (d_.wordv[0]&1)){
bigint_shiftright(&d_, 1);
}
-#if DEBUG
- cli_putstr_P(PSTR("\r\n if u>=v ..."));
- cli_putstr_P(PSTR("\r\nDBG: (30) a = "));
- bigint_print_hex(&a_);
- cli_putstr_P(PSTR("\r\nDBG: (30) b = "));
- bigint_print_hex(&b_);
- cli_putstr_P(PSTR("\r\nDBG: (30) c = "));
- bigint_print_hex(&c_);
- cli_putstr_P(PSTR("\r\nDBG: (30) d = "));
- bigint_print_hex(&d_);
-#endif
if(bigint_cmp_u(&u, &v)>=0){
bigint_sub_u(&u, &u, &v);
bigint_sub_s(&a_, &a_, &c_);
bigint_sub_s(&c_, &c_, &a_);
bigint_sub_s(&d_, &d_, &b_);
}
-#if DEBUG
- if(GET_SIGN(&u)){
- cli_putstr_P(PSTR("\r\nDBG: u negative! u = "));
- bigint_print_hex(&u);
- }
- if(GET_SIGN(&v)){
- cli_putstr_P(PSTR("\r\nDBG: v negative! v = "));
- bigint_print_hex(&v);
- }
-#endif
-/*
- cli_putstr_P(PSTR("\r\nDBG: (2) a = "));
- bigint_print_hex(&a_);
- cli_putstr_P(PSTR("\r\nDBG: (2) b = "));
- bigint_print_hex(&b_);
- cli_putstr_P(PSTR("\r\nDBG: (2) c = "));
- bigint_print_hex(&c_);
- cli_putstr_P(PSTR("\r\nDBG: (2) d = "));
- bigint_print_hex(&d_);
-*/
}while(u.length_B);
if(gcd){
bigint_mul_s(gcd, &v, &g);
/******************************************************************************/
-void bigint_inverse(bigint_t* dest, bigint_t* a, bigint_t* m){
+void bigint_inverse(bigint_t* dest, const bigint_t* a, const bigint_t* m){
bigint_gcdext(NULL, dest, NULL, a, m);
while(dest->info&BIGINT_NEG_MASK){
bigint_add_s(dest, dest, m);
}
}
+/******************************************************************************/
+
+void bigint_changeendianess(bigint_t* a){
+ uint8_t t, *p, *q;
+ p = a->wordv;
+ q = p+a->length_B-1;
+ while(p<q){
+ t = *p;
+ *p = *q;
+ *q = t;
+ ++p; --q;
+ }
+}
+/******************************************************************************/
projects / avr-crypto-lib.git / blobdiff