#define SET_NEG(a) (a)->info |= BIGINT_NEG_MASK
#define SET_POS(a) (a)->info &= ~BIGINT_NEG_MASK
#define XCHG(a,b) do{(a)^=(b); (b)^=(a); (a)^=(b);}while(0)
-#define XCHG_PTR(a,b) do{ a = (void*)(((bigint_ptr_int_t)(a)) ^ ((bigint_ptr_int_t)(b))); \
- b = (void*)(((bigint_ptr_int_t)(a)) ^ ((bigint_ptr_int_t)(b))); \
- a = (void*)(((bigint_ptr_int_t)(a)) ^ ((bigint_ptr_int_t)(b)));}while(0)
+#define XCHG_PTR(a,b) do{ a = (void*)(((intptr_t)(a)) ^ ((intptr_t)(b))); \
+ b = (void*)(((intptr_t)(a)) ^ ((intptr_t)(b))); \
+ a = (void*)(((intptr_t)(a)) ^ ((intptr_t)(b)));}while(0)
#define GET_SIGN(a) ((a)->info&BIGINT_NEG_MASK)
/******************************************************************************/
-uint16_t bigint_length_b(bigint_t* a){
+uint16_t bigint_length_b(const bigint_t* a){
if(!a->length_B || a->length_B==0){
return 0;
}
/******************************************************************************/
-uint16_t bigint_length_B(bigint_t* a){
+uint16_t bigint_length_B(const bigint_t* a){
return a->length_B * sizeof(bigint_word_t);
}
/******************************************************************************/
-uint32_t bigint_get_first_set_bit(bigint_t* a){
+uint32_t bigint_get_first_set_bit(const bigint_t* a){
if(a->length_B==0){
return (uint32_t)(-1);
}
/******************************************************************************/
-uint32_t bigint_get_last_set_bit(bigint_t* a){
+uint32_t bigint_get_last_set_bit(const bigint_t* a){
uint32_t r=0;
uint8_t b=0;
bigint_word_t x=1;
/* this should be implemented in assembly */
void bigint_add_u(bigint_t* dest, const bigint_t* a, const bigint_t* b){
uint16_t i;
- bigint_wordplus_t t=0LL;
+ bigint_wordplus_t t = 0LL;
if(a->length_B < b->length_B){
XCHG_PTR(a,b);
}
- for(i=0; i<b->length_B; ++i){
-// t = (bigint_wordplus_t)(a->wordv[i]) + (bigint_wordplus_t)(b->wordv[i]) + t;
+ for(i = 0; i < b->length_B; ++i){
t += a->wordv[i];
t += b->wordv[i];
dest->wordv[i] = (bigint_word_t)t;
- t>>=BIGINT_WORD_SIZE;
+ t >>= BIGINT_WORD_SIZE;
}
- for(; i<a->length_B; ++i){
+ for(; i < a->length_B; ++i){
t += a->wordv[i];
dest->wordv[i] = (bigint_word_t)t;
- t>>=BIGINT_WORD_SIZE;
+ t >>= BIGINT_WORD_SIZE;
+ }
+ if(t){
+ dest->wordv[i++] = (bigint_word_t)t;
}
- dest->wordv[i++] = (bigint_word_t)t;
dest->length_B = i;
bigint_adjust(dest);
}
/* this should be implemented in assembly */
void bigint_add_scale_u(bigint_t* dest, const bigint_t* a, uint16_t scale){
- bigint_t x;
+ if(a->length_B == 0){
+ return;
+ }
+ if(scale == 0){
+ bigint_add_u(dest, dest, a);
+ return;
+ }
+#if DEBUG_ADD_SCALE
+ cli_putstr_P(PSTR("\r\nDBG: bigint_add_scale("));
+ bigint_print_hex(dest);
+ cli_putc(',');
+ bigint_print_hex(dest);
+ cli_putc(',');
+ cli_hexdump_rev(&scale, 2);
+ cli_putc(')');
+#endif
#if BIGINT_WORD_SIZE == 8
- memset(dest->wordv + dest->length_B, 0, MAX(dest->length_B, a->length_B + scale) - dest->length_B);
- x.wordv = dest->wordv + scale;
+ if(scale >= dest->length_B){
+#if DEBUG_ADD_SCALE
+ cli_putstr_P(PSTR("\r\n\tpath one"));
+#endif
+ memset(dest->wordv + dest->length_B, 0, scale - dest->length_B);
+ memcpy(dest->wordv + scale, a->wordv, a->length_B);
+ dest->info = a->info;
+ dest->length_B = a->length_B + scale;
+ return;
+ }
+ bigint_t x;
+#if DEBUG_ADD_SCALE
+ cli_putstr_P(PSTR("\r\n\tpath two"));
+#endif
x.length_B = dest->length_B - scale;
- if((int16_t)x.length_B < 0)
- x.length_B = 0;
x.info = dest->info;
+ x.wordv = dest->wordv + scale;
bigint_add_u(&x, &x, a);
dest->length_B = x.length_B + scale;
dest->info = 0;
bigint_adjust(dest);
#else
-#error unimplemented!
+ bigint_t s;
+ uint16_t word_shift = scale / sizeof(bigint_word_t), byte_shift = scale % sizeof(bigint_word_t);
+ bigint_word_t bv[a->length_B + 1];
+ s.wordv = bv;
+ bv[0] = bv[a->length_B] = 0;
+ memcpy((uint8_t*)bv + byte_shift, a->wordv, a->length_B * sizeof(bigint_word_t));
+ s.length_B = a->length_B + 1;
+ bigint_adjust(&s);
+ memset(dest->wordv + dest->length_B, 0, (MAX(dest->length_B, s.length_B + word_shift) - dest->length_B) * sizeof(bigint_word_t));
+ x.wordv = dest->wordv + word_shift;
+ x.length_B = dest->length_B - word_shift;
+ if((int16_t)x.length_B < 0){
+ x.length_B = 0;
+ x.info = 0;
+ }else{
+ x.info = dest->info;
+ }
+ bigint_add_u(&x, &x, &s);
+ dest->length_B = x.length_B + word_shift;
+ dest->info = 0;
+ bigint_adjust(dest);
#endif
int8_t borrow=0;
int8_t r;
bigint_wordplus_signed_t t=0LL;
- uint16_t i, min, max;
- min = MIN(a->length_B, b->length_B);
- max = MAX(a->length_B, b->length_B);
+ uint16_t i;
r = bigint_cmp_u(a,b);
if(r==0){
bigint_set_zero(dest);
SET_NEG(dest);
return;
}
- for(i=0; i<max; ++i){
+ for(i=0; i < a->length_B; ++i){
t = a->wordv[i];
- if(i<min){
+ if(i < b->length_B){
t -= b->wordv[i];
}
t -= borrow;
void bigint_add_s(bigint_t* dest, const bigint_t* a, const bigint_t* b){
uint8_t s;
- int8_t d = 0;
s = GET_SIGN(a)?2:0;
s |= GET_SIGN(b)?1:0;
switch(s){
case 0: /* both positive */
- d = 1;
bigint_add_u(dest, a,b);
+ SET_POS(dest);
break;
case 1: /* a positive, b negative */
- d = bigint_cmp_u(a,b);
bigint_sub_u(dest, a, b);
break;
case 2: /* a negative, b positive */
- d = bigint_cmp_u(b,a);
bigint_sub_u(dest, b, a);
break;
case 3: /* both negative */
- d = -1;
bigint_add_u(dest, a, b);
+ SET_NEG(dest);
break;
default: /* how can this happen?*/
break;
}
- if(d<0){
- SET_NEG(dest);
- }else{
- SET_POS(dest);
- }
}
/******************************************************************************/
/******************************************************************************/
void bigint_shiftleft(bigint_t* a, uint16_t shift){
- uint16_t byteshift, word_alloc;
+ uint16_t byteshift, words_to_shift;
int16_t i;
uint8_t bitshift;
bigint_word_t *p;
bigint_wordplus_t t=0;
- if(shift==0){
+ if(shift == 0){
return;
}
- byteshift = shift/8;
- bitshift = shift&7;
- for(i=0;i<=byteshift/sizeof(bigint_word_t); ++i){
- a->wordv[a->length_B+i] = 0;
- }
+ byteshift = shift / 8;
+ bitshift = shift & 7;
+ memset(&a->wordv[a->length_B], 0x00, byteshift);
if(byteshift){
- memmove(((uint8_t*)a->wordv)+byteshift, a->wordv, a->length_B*sizeof(bigint_word_t));
+ memmove(((uint8_t*)a->wordv)+byteshift, a->wordv, a->length_B * sizeof(bigint_word_t));
memset(a->wordv, 0, byteshift);
}
- p = (bigint_word_t*)(((uint8_t*)a->wordv)+byteshift);
- word_alloc = a->length_B+(byteshift+sizeof(bigint_word_t)-1)/sizeof(bigint_word_t)+1;
- a->wordv[word_alloc-1]=0;
- if(bitshift!=0){
- for(i=0; i<a->length_B; ++i){
- t |= ((bigint_wordplus_t)p[i])<<bitshift;
+ if(bitshift != 0){
+ p = (bigint_word_t*)((uint8_t*)a->wordv + byteshift / sizeof(bigint_word_t));
+ words_to_shift = a->length_B + ((byteshift % sizeof(bigint_word_t))?1:0);
+ /* XXX */
+ for(i = 0; i < words_to_shift; ++i){
+ t |= ((bigint_wordplus_t)p[i]) << bitshift;
p[i] = (bigint_word_t)t;
t >>= BIGINT_WORD_SIZE;
}
p[i] = (bigint_word_t)t;
}
- a->length_B = word_alloc;
+ a->length_B += (shift + BIGINT_WORD_SIZE - 1) / BIGINT_WORD_SIZE;
bigint_adjust(a);
}
bigint_wordplus_t t=0;
byteshift = shift/8;
bitshift = shift&7;
- if(byteshift >= a->length_B*sizeof(bigint_word_t)){ /* we would shift out more than we have */
+ if(byteshift >= a->length_B * sizeof(bigint_word_t)){ /* we would shift out more than we have */
bigint_set_zero(a);
return;
}
- if(byteshift == a->length_B*sizeof(bigint_word_t)-1 && bitshift>GET_FBS(a)){
+ if(byteshift == a->length_B * sizeof(bigint_word_t) - 1 && bitshift > GET_FBS(a)){
bigint_set_zero(a);
return;
}
if(byteshift){
- memmove(a->wordv, (uint8_t*)a->wordv+byteshift, a->length_B-byteshift);
- memset((uint8_t*)a->wordv+a->length_B-byteshift, 0, byteshift);
+ memmove(a->wordv, (uint8_t*)a->wordv + byteshift, a->length_B * sizeof(bigint_word_t) - byteshift);
+ memset((uint8_t*)a->wordv + a->length_B * sizeof(bigint_word_t) - byteshift, 0, byteshift);
}
byteshift /= sizeof(bigint_word_t);
- if(bitshift!=0){
+ a->length_B -= (byteshift + sizeof(bigint_word_t) - 1) / sizeof(bigint_word_t);
+ if(bitshift != 0 && a->length_B){
/* shift to the right */
- for(i=a->length_B-byteshift-1; i>0; --i){
- t |= ((bigint_wordplus_t)(a->wordv[i]))<<(BIGINT_WORD_SIZE-bitshift);
- a->wordv[i] = (bigint_word_t)(t>>BIGINT_WORD_SIZE);
+ i = a->length_B - 1;
+ do{
+ t |= ((bigint_wordplus_t)(a->wordv[i])) << (BIGINT_WORD_SIZE - bitshift);
+ a->wordv[i] = (bigint_word_t)(t >> BIGINT_WORD_SIZE);
t <<= BIGINT_WORD_SIZE;
- }
- t |= ((bigint_wordplus_t)(a->wordv[0]))<<(BIGINT_WORD_SIZE-bitshift);
- a->wordv[0] = (bigint_word_t)(t>>BIGINT_WORD_SIZE);
+ }while(i--);
}
- a->length_B -= ((shift/8)+sizeof(bigint_word_t)-1)/sizeof(bigint_word_t);
bigint_adjust(a);
}
}
if(dest==a || dest==b){
bigint_t d;
- bigint_word_t d_b[a->length_B+b->length_B];
+ bigint_word_t d_b[a->length_B + b->length_B];
d.wordv = d_b;
bigint_mul_u(&d, a, b);
bigint_copy(dest, &d);
return;
}
if(a->length_B==1 || b->length_B==1){
- if(a->length_B!=1){
+ if(a->length_B != 1){
XCHG_PTR(a,b);
}
bigint_wordplus_t t=0;
uint16_t i;
bigint_word_t x = a->wordv[0];
for(i=0; i < b->length_B; ++i){
- t += ((bigint_wordplus_t)b->wordv[i])*((bigint_wordplus_t)x);
+ t += ((bigint_wordplus_t)b->wordv[i]) * ((bigint_wordplus_t)x);
dest->wordv[i] = (bigint_word_t)t;
t>>=BIGINT_WORD_SIZE;
}
bigint_adjust(dest);
return;
}
- bigint_set_zero(dest);
+#if BIGINT_WORD_SIZE == 8
+ if(a->length_B <= 4 || b->length_B <= 4){
+ if(a->length_B > 4){
+ XCHG_PTR(a,b);
+ }
+ uint32_t x = 0, y = 0;
+ uint16_t j = b->length_B / 4, idx = 0;
+ uint64_t r = 0;
+ memcpy(&x, a->wordv, a->length_B);
+ while(j){
+ r += (uint64_t)((uint32_t*)b->wordv)[idx] * (uint64_t)x;
+ ((uint32_t*)dest->wordv)[idx] = (uint32_t)r;
+ r >>= 32;
+ ++idx;
+ --j;
+ }
+ idx *= 4;
+ memcpy(&y, b->wordv + idx, b->length_B - idx);
+ r += (uint64_t)y * (uint64_t)x;
+ while(r){
+ dest->wordv[idx++] = (uint8_t)r;
+ r >>= 8;
+ }
+ dest->length_B = idx;
+ bigint_adjust(dest);
+ return;
+ }
+#endif
/* split a in xh & xl; split b in yh & yl */
const uint16_t n = (MAX(a->length_B, b->length_B)+1)/2;
bigint_t xl, xh, yl, yh;
xl.wordv = a->wordv;
yl.wordv = b->wordv;
- if(a->length_B<=n){
+ if(a->length_B <= n){
bigint_set_zero(&xh);
xl.length_B = a->length_B;
xl.info = a->info;
}else{
- xl.length_B=n;
+ xl.length_B = n;
xl.info = 0;
bigint_adjust(&xl);
xh.wordv = &(a->wordv[n]);
xh.length_B = a->length_B-n;
xh.info = a->info;
}
- if(b->length_B<=n){
+ if(b->length_B <= n){
bigint_set_zero(&yh);
yl.length_B = b->length_B;
yl.info = b->info;
}else{
- yl.length_B=n;
+ yl.length_B = n;
yl.info = 0;
bigint_adjust(&yl);
yh.wordv = &(b->wordv[n]);
}
/* now we have split up a and b */
/* remember we want to do:
- * x*y = (xh*yh)*b**2n + ((xh+xl)*(yh+yl) - xh*yh - xl*yl)*b**n + yh*yl
+ * x*y = (xh * b ** n + xl) * (yh * b ** n + yl)
+ * x*y = (xh*yh)*b**2n + ((xh+xl)*(yh+yl) - xh*yh - xl*yl)*b**n + xl*yl
* 5 9 2 4 3 7 5 6 1 8 1
*/
- bigint_word_t tmp_b[2*n+2], m_b[2*(n+1)];
- bigint_t tmp, tmp2, m;
- tmp.wordv = tmp_b;
- tmp2.wordv = &(tmp_b[n+1]);
- m.wordv = m_b;
-
- bigint_mul_u(dest, &xl, &yl); /* 1: dest <= xl*yl */
- bigint_add_u(&tmp2, &xh, &xl); /* 2: tmp2 <= xh+xl */
- bigint_add_u(&tmp, &yh, &yl); /* 3: tmp <= yh+yl */
- bigint_mul_u(&m, &tmp2, &tmp); /* 4: m <= tmp2*tmp */
- bigint_mul_u(&tmp, &xh, &yh); /* 5: h <= xh*yh */
- bigint_sub_u(&m, &m, dest); /* 6: m <= m-dest */
- bigint_sub_u(&m, &m, &tmp); /* 7: m <= m-h */
- bigint_add_scale_u(dest, &m, n*sizeof(bigint_word_t)); /* 8: dest <= dest+m**n*/
- bigint_add_scale_u(dest, &tmp, 2*n*sizeof(bigint_word_t)); /* 9: dest <= dest+tmp**(2*n) */
+ bigint_word_t tmp1_b[n*2+2];
+ bigint_t tmp1, tmp2;
+ tmp1.wordv = tmp1_b;
+ tmp2.wordv = &tmp1_b[n+1];
+
+ bigint_add_u(&tmp2, &xh, &xl); /* 2: tmp2 <= xh + xl */
+ bigint_add_u(&tmp1, &yh, &yl); /* 3: tmp1 <= yh + yl */
+ bigint_mul_u(dest, &tmp2, &tmp1); /* 4: dest <= tmp2 * tmp1 */
+ bigint_mul_u(&tmp1, &xh, &yh); /* 5: tmp1 <= xh * yh */
+ bigint_sub_u(dest, dest, &tmp1); /* 7: dest <= dest - tmp1 */
+ bigint_word_t tmp3_b[2*n];
+ tmp2.wordv = tmp3_b;
+ bigint_mul_u(&tmp2, &xl, &yl); /* 1: tmp3 <= xl * yl */
+ bigint_sub_u(dest, dest, &tmp2); /* 6: dest <= dest - tmp3 */
+ bigint_shiftleft(dest, n * sizeof(bigint_word_t) * 8);
+ bigint_add_u(dest, dest, &tmp2); /* 8: dest <= tmp3 + dest ** n */
+ bigint_add_scale_u(dest, &tmp1, 2*n*sizeof(bigint_word_t)); /* 9: dest <= dest + tmp1 ** (2 * n) */
+
+#if 0
+ bigint_mul_u(dest, &xl, &yl); /* 1: dest <= xl * yl */
+ bigint_add_u(&tmp2, &xh, &xl); /* 2: tmp2 <= xh + xl */
+ bigint_add_u(&tmp1, &yh, &yl); /* 3: tmp1 <= yh + yl */
+ bigint_mul_u(&tmp3, &tmp2, &tmp1); /* 4: tmp3 <= tmp2 * tmp1 */
+ bigint_mul_u(&tmp1, &xh, &yh); /* 5: h <= xh * yh */
+ bigint_sub_u(&tmp3, &tmp3, dest); /* 6: tmp3 <= tmp3 - dest */
+ bigint_sub_u(&tmp3, &tmp3, &tmp1); /* 7: tmp3 <= tmp3 - h */
+ bigint_add_scale_u(dest, &tmp3, n*sizeof(bigint_word_t)); /* 8: dest <= dest + tmp3 ** n */
+ bigint_add_scale_u(dest, &tmp1, 2*n*sizeof(bigint_word_t)); /* 9: dest <= dest + tmp1 ** (2 * n) */
+#endif
}
/******************************************************************************/
/* square */
/* (xh*b^n+xl)^2 = xh^2*b^2n + 2*xh*xl*b^n + xl^2 */
void bigint_square(bigint_t* dest, const bigint_t* a){
- if(a->length_B*sizeof(bigint_word_t)<=4){
- uint64_t r=0;
- memcpy(&r, a->wordv, a->length_B*sizeof(bigint_word_t));
- r = r*r;
- memcpy(dest->wordv, &r, 2*a->length_B*sizeof(bigint_word_t));
+ if(a->length_B * sizeof(bigint_word_t) <= 4){
+ uint64_t r = 0;
+ memcpy(&r, a->wordv, a->length_B * sizeof(bigint_word_t));
+ r = r * r;
+ memcpy(dest->wordv, &r, 2 * a->length_B*sizeof(bigint_word_t));
SET_POS(dest);
- dest->length_B=2*a->length_B;
+ dest->length_B = 2 * a->length_B;
bigint_adjust(dest);
return;
}
if(dest==a){
bigint_t d;
- bigint_word_t d_b[a->length_B*2];
+ bigint_word_t d_b[a->length_B * 2];
d.wordv = d_b;
bigint_square(&d, a);
bigint_copy(dest, &d);
return;
}
uint16_t n;
- n=(a->length_B+1)/2;
+ n = (a->length_B + 1) / 2;
bigint_t xh, xl, tmp; /* x-high, x-low, temp */
- bigint_word_t buffer[2*n+1];
+ bigint_word_t buffer[2 * n + 1];
xl.wordv = a->wordv;
xl.length_B = n;
xl.info = 0;
xh.wordv = &(a->wordv[n]);
- xh.length_B = a->length_B-n;
- xh.info = 0;
+ xh.length_B = a->length_B - n;
+ xh.info = a->info;
bigint_adjust(&xl);
- bigint_adjust(&xh);
tmp.wordv = buffer;
/* (xh * b**n + xl)**2 = xh**2 * b**2n + 2 * xh * xl * b**n + xl**2 */
// cli_putstr("\r\nDBG (1): xl**2: "); bigint_print_hex(dest);
bigint_square(&tmp, &xh);
// cli_putstr("\r\nDBG (2): xh**2: "); bigint_print_hex(&tmp);
- bigint_add_scale_u(dest, &tmp, 2*n*sizeof(bigint_word_t));
+ bigint_add_scale_u(dest, &tmp, 2 * n * sizeof(bigint_word_t));
// cli_putstr("\r\nDBG (3): xl**2 + xh**2*n**2: "); bigint_print_hex(dest);
bigint_mul_u(&tmp, &xl, &xh);
// cli_putstr("\r\nDBG (4): xl*xh: "); bigint_print_hex(&tmp);
bigint_copy(&tmp, b);
bigint_shiftleft(&tmp, bitscale % BIGINT_WORD_SIZE);
+// cli_putstr_P(PSTR("\r\nDBG: shifted value: ")); bigint_print_hex(&tmp);
+
x.info = a->info;
x.wordv = &(a->wordv[word_shift]);
x.length_B = a->length_B - word_shift;
bigint_sub_u(&x, &x, &tmp);
+ a->length_B = x.length_B + word_shift;
bigint_adjust(a);
return;
}
}
while((GET_FBS(a) > rfbs) && (a->length_B == r->length_B)){
shift = GET_FBS(a)-rfbs-1;
+// cli_putstr("\r\nDBG: (2a) = "); bigint_print_hex(a);
// cli_putstr("\r\nDBG: (q) shift = "); cli_hexdump_rev(&shift, 2);
bigint_sub_u_bitscale(a, r, shift);
-// cli_putstr("\r\nDBG: (2) = "); bigint_print_hex(a);
+// cli_putstr("\r\nDBG: (2b) = "); bigint_print_hex(a);
}
while(bigint_cmp_u(a,r)>=0){
bigint_sub_u(a,a,r);
// cli_putstr("\r\nDBG: (3) = "); bigint_print_hex(a);
}
+// cli_putc(' ');
bigint_adjust(a);
// cli_putstr("\r\nDBG: (a) = "); bigint_print_hex(a);
// cli_putstr("\r\n");
void bigint_changeendianess(bigint_t* a){
uint8_t t, *p, *q;
p = (uint8_t*)(a->wordv);
- q = ((uint8_t*)p)+a->length_B*sizeof(bigint_word_t)-1;
+ q = p + a->length_B * sizeof(bigint_word_t) - 1;
while(p<q){
t = *p;
*p = *q;