bug fixing and support for malloc instead of stack memory (some functions)

diff --git a/bigint/bigint.c b/bigint/bigint.c
index 8524daad3b66a042439307f080d024776e8f474d..d868a498ddf7f23dc642c4fb35b2fa5ce47be87c 100644 (file)
--- a/bigint/bigint.c
+++ b/bigint/bigint.c
@@ -33,6 +33,21 @@
 #include "bigint.h"
 #include <string.h>
 
+#define PREFERE_HEAP_SPACE 1
+
+#if PREFERE_HEAP_SPACE
+#include <stdlib.h>
+
+#define ALLOC_BIGINT_WORDS(var,words) bigint_word_t *(var) = malloc((words) * sizeof(bigint_word_t))
+#define FREE(x) free(x)
+
+#else
+
+#define ALLOC_BIGINT_WORDS(var,words) bigint_word_t var[words]
+#define FREE(x)
+
+#endif
+
 #define DEBUG 1
 
 #if DEBUG || 1
@@ -367,12 +382,26 @@ int8_t bigint_cmp_s(const bigint_t *a, const bigint_t *b){
 
 /******************************************************************************/
 
+void bigint_shiftleft_bits(bigint_t *a, uint8_t shift) {
+    bigint_length_t i;
+    bigint_wordplus_t t = 0;
+
+    for (i = 0; i < a->length_W; ++i) {
+        t |= ((bigint_wordplus_t)a->wordv[i]) << shift;
+        a->wordv[i] = (bigint_word_t)t;
+        t >>= BIGINT_WORD_SIZE;
+    }
+    if (t) {
+        a->wordv[a->length_W++] = (bigint_word_t)t;
+    }
+    bigint_adjust(a);
+}
+
+/******************************************************************************/
+
 void bigint_shiftleft(bigint_t *a, bigint_length_t shift){
-       bigint_length_t byteshift, words_to_shift;
-       int16_t i;
+       bigint_length_t byteshift;
        uint8_t bitshift;
-       bigint_word_t *p;
-       bigint_wordplus_t t = 0;
 
        if (a->length_W == 0 || shift == 0) {
                return;
@@ -385,36 +414,63 @@ void bigint_shiftleft(bigint_t *a, bigint_length_t shift){
        if (byteshift) {
                memmove(((uint8_t*)a->wordv) + byteshift, a->wordv, a->length_W * sizeof(bigint_word_t));
                memset(a->wordv, 0, byteshift);
+        a->length_W += (byteshift + sizeof(bigint_word_t) - 1) / sizeof(bigint_word_t);
        }
+
        if (bitshift == 0) {
-           a->length_W += (byteshift + sizeof(bigint_word_t) - 1) / sizeof(bigint_word_t);
            bigint_adjust(a);
-           return;
+       } else {
+           bigint_shiftleft_bits(a, bitshift);
        }
-       p = &a->wordv[byteshift / sizeof(bigint_word_t)];
-       words_to_shift = a->length_W + (byteshift % sizeof(bigint_word_t) ? 1 : 0);
-    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;
+}
+
+/******************************************************************************/
+
+void bigint_shiftright_bits(bigint_t *a, uint8_t shift){
+    bigint_length_t i;
+    bigint_wordplus_t t = 0;
+
+    i = a->length_W;
+    while (i--) {
+        t |= ((bigint_wordplus_t)(a->wordv[i])) << (BIGINT_WORD_SIZE - shift);
+        a->wordv[i] = (bigint_word_t)(t >> BIGINT_WORD_SIZE);
+        t <<= BIGINT_WORD_SIZE;
     }
-    if (t) {
-        p[i] = (bigint_word_t)t;
-        a->length_W += 1;
+
+    bigint_adjust(a);
+}
+
+/******************************************************************************/
+
+void bigint_shiftright_1bit(bigint_t *a){
+    bigint_length_t i;
+    bigint_word_t t1 = 0, t2;
+
+    i = a->length_W;
+    while (i--) {
+        t2 = a->wordv[i] & 1;
+        a->wordv[i] >>= 1;
+        a->wordv[i] |= t1;
+        t1 = t2 << (BIGINT_WORD_SIZE - 1);
     }
-    a->length_W += (byteshift + sizeof(bigint_word_t) - 1) / sizeof(bigint_word_t);
     bigint_adjust(a);
 }
 
 /******************************************************************************/
 
+void bigint_shiftright_1word(bigint_t *a){
+    if (a->length_W == 0) {
+        return;
+    }
+    memmove(a->wordv, &a->wordv[1], (a->length_W - 1) * sizeof(bigint_word_t));
+    a->length_W--;
+}
+
+/******************************************************************************/
+
 void bigint_shiftright(bigint_t *a, bigint_length_t shift){
-       bigint_length_t byteshift;
-       bigint_length_t i;
-       uint8_t bitshift;
-       bigint_wordplus_t t = 0;
-       byteshift = shift / 8;
-       bitshift = shift & 7;
+       bigint_length_t byteshift = shift / 8;
+       uint8_t bitshift = shift & 7;
 
        if (a->length_W == 0) {
            return;
@@ -429,19 +485,12 @@ void bigint_shiftright(bigint_t *a, bigint_length_t shift){
                memmove(a->wordv, (uint8_t*)a->wordv + byteshift, a->length_W * sizeof(bigint_word_t) - byteshift);
                memset((uint8_t*)&a->wordv[a->length_W] - byteshift, 0, byteshift);
            a->length_W -= byteshift / sizeof(bigint_word_t);
+           bigint_adjust(a);
        }
 
-
-    if(bitshift != 0 && a->length_W){
-        /* shift to the right */
-               i = a->length_W - 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;
-               }while(i--);
+    if(bitshift != 0){
+        bigint_shiftright_bits(a, bitshift);
        }
-       bigint_adjust(a);
 }
 
 /******************************************************************************/
@@ -457,7 +506,7 @@ void bigint_xor(bigint_t *dest, const bigint_t *a){
 /******************************************************************************/
 
 void bigint_set_zero(bigint_t *a){
-       a->length_W=0;
+       a->length_W = 0;
 }
 
 /******************************************************************************/
@@ -465,11 +514,11 @@ void bigint_set_zero(bigint_t *a){
 /* 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_W == 0 || b->length_W == 0){
+       if (a->length_W == 0 || b->length_W == 0) {
                bigint_set_zero(dest);
                return;
        }
-       if(dest == a || dest == b){
+       if (dest == a || dest == b) {
                bigint_t d;
                bigint_word_t d_b[a->length_W + b->length_W];
                d.wordv = d_b;
@@ -477,20 +526,20 @@ void bigint_mul_u(bigint_t *dest, const bigint_t *a, const bigint_t *b){
                bigint_copy(dest, &d);
                return;
        }
-       if(a->length_W == 1 || b->length_W == 1){
-               if(a->length_W != 1){
+       if (a->length_W == 1 || b->length_W == 1) {
+               if (a->length_W != 1) {
                        XCHG_PTR(a,b);
                }
                bigint_wordplus_t t = 0;
                bigint_length_t i;
                bigint_word_t x = a->wordv[0];
-               for(i=0; i < b->length_W; ++i){
+               for (i = 0; i < b->length_W; ++i) {
                        t += ((bigint_wordplus_t)b->wordv[i]) * ((bigint_wordplus_t)x);
                        dest->wordv[i] = (bigint_word_t)t;
                        t >>= BIGINT_WORD_SIZE;
                }
                dest->length_W = i;
-               if(t){
+               if (t) {
                    dest->wordv[i] = (bigint_word_t)t;
                    dest->length_W += 1;
                }
@@ -498,39 +547,39 @@ void bigint_mul_u(bigint_t *dest, const bigint_t *a, const bigint_t *b){
                bigint_adjust(dest);
                return;
        }
-       if(a->length_W * sizeof(bigint_word_t) <= 4 && b->length_W * sizeof(bigint_word_t) <= 4){
-               uint32_t p=0, q=0;
+       if (a->length_W * sizeof(bigint_word_t) <= 4 && b->length_W * sizeof(bigint_word_t) <= 4) {
+               uint32_t p = 0, q = 0;
                uint64_t r;
-               memcpy(&p, a->wordv, a->length_W*sizeof(bigint_word_t));
-               memcpy(&q, b->wordv, b->length_W*sizeof(bigint_word_t));
+               memcpy(&p, a->wordv, a->length_W * sizeof(bigint_word_t));
+               memcpy(&q, b->wordv, b->length_W * sizeof(bigint_word_t));
                r = (uint64_t)p * (uint64_t)q;
-               memcpy(dest->wordv, &r, (dest->length_W = a->length_W + b->length_W)*sizeof(bigint_word_t));
+               memcpy(dest->wordv, &r, (dest->length_W = a->length_W + b->length_W) * sizeof(bigint_word_t));
                bigint_adjust(dest);
                return;
        }
        /* split a in xh & xl; split b in yh & yl */
-       const bigint_length_t n = (MAX(a->length_W, b->length_W)+1)/2;
+       const bigint_length_t n = (MAX(a->length_W, b->length_W) + 1) / 2;
        bigint_t xl, xh, yl, yh;
        xl.wordv = a->wordv;
        yl.wordv = b->wordv;
-       if(a->length_W<=n){
+       if (a->length_W <= n) {
                bigint_set_zero(&xh);
                xl.length_W = a->length_W;
                xl.info = a->info;
-       }else{
-               xl.length_W=n;
+       } else {
+               xl.length_W = n;
                xl.info = 0;
                bigint_adjust(&xl);
                xh.wordv = &(a->wordv[n]);
                xh.length_W = a->length_W-n;
                xh.info = a->info;
        }
-       if(b->length_W<=n){
+       if (b->length_W <= n) {
                bigint_set_zero(&yh);
                yl.length_W = b->length_W;
                yl.info = b->info;
-       }else{
-               yl.length_W=n;
+       } else {
+               yl.length_W = n;
                yl.info = 0;
                bigint_adjust(&yl);
                yh.wordv = &(b->wordv[n]);
@@ -546,11 +595,12 @@ void bigint_mul_u(bigint_t *dest, const bigint_t *a, const bigint_t *b){
         * 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)];
+       ALLOC_BIGINT_WORDS(tmp_w, 2 * n + 2);
+       ALLOC_BIGINT_WORDS(m_w, 2 * n + 2);
        bigint_t tmp, tmp2, m;
-       tmp.wordv = tmp_b;
-       tmp2.wordv = &(tmp_b[n + 1]);
-       m.wordv = m_b;
+       tmp.wordv = tmp_w;
+       tmp2.wordv = &(tmp_w[n + 1]);
+       m.wordv = m_w;
 
        bigint_mul_u(dest, &xl, &yl);  /* 1: dest <= xl*yl     */
        bigint_add_u(&tmp2, &xh, &xl); /* 2: tmp2 <= xh+xl     */
@@ -561,6 +611,8 @@ void bigint_mul_u(bigint_t *dest, const bigint_t *a, const bigint_t *b){
     bigint_sub_u(&m, &m, &tmp);    /* 7: m    <= m-tmp     */
        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) */
+       FREE(m_w);
+       FREE(tmp_w);
 }
 
 /******************************************************************************/
@@ -591,102 +643,6 @@ void bigint_mul_s(bigint_t *dest, const bigint_t *a, const bigint_t *b){
        }
 }
 
-/******************************************************************************/
-#if OLD_SQUARE
-
-#if DEBUG_SQUARE
-unsigned square_depth = 0;
-#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_W * sizeof(bigint_word_t) <= 4){
-               uint64_t r = 0;
-               memcpy(&r, a->wordv, a->length_W * sizeof(bigint_word_t));
-               r = r * r;
-               memcpy(dest->wordv, &r, 2 * a->length_W * sizeof(bigint_word_t));
-               SET_POS(dest);
-               dest->length_W = 2 * a->length_W;
-               bigint_adjust(dest);
-               return;
-       }
-
-       if(dest->wordv == a->wordv){
-               bigint_t d;
-               bigint_word_t d_b[a->length_W*2];
-               d.wordv = d_b;
-               bigint_square(&d, a);
-               bigint_copy(dest, &d);
-               return;
-       }
-       bigint_fast_square(dest, a);
-       return;
-#if DEBUG_SQUARE
-       square_depth += 1;
-#endif
-
-       bigint_length_t n;
-       n=(a->length_W+1)/2;
-       bigint_t xh, xl, tmp; /* x-high, x-low, temp */
-       bigint_word_t buffer[2*n+1];
-       xl.wordv = a->wordv;
-       xl.length_W = n;
-       xl.info = 0;
-       xh.wordv = &(a->wordv[n]);
-       xh.length_W = a->length_W-n;
-       xh.info = a->info;
-       bigint_adjust(&xl);
-       tmp.wordv = buffer;
-/* (xh * b**n + xl)**2 = xh**2 * b**2n + 2 * xh * xl * b**n + xl**2 */
-#if DEBUG_SQUARE
-       if(square_depth == 1){
-        cli_putstr("\r\nDBG (a): xl: "); bigint_print_hex(&xl);
-        cli_putstr("\r\nDBG (b): xh: "); bigint_print_hex(&xh);
-       }
-#endif
-       bigint_square(dest, &xl);
-#if DEBUG_SQUARE
-       if(square_depth == 1){
-           cli_putstr("\r\nDBG (1): xl**2: "); bigint_print_hex(dest);
-       }
-#endif
-    bigint_square(&tmp, &xh);
-#if DEBUG_SQUARE
-    if(square_depth == 1){
-        cli_putstr("\r\nDBG (2): xh**2: "); bigint_print_hex(&tmp);
-    }
-#endif
-       bigint_add_scale_u(dest, &tmp, 2 * n * sizeof(bigint_word_t));
-#if DEBUG_SQUARE
-       if(square_depth == 1){
-           cli_putstr("\r\nDBG (3): xl**2 + xh**2*n**2: "); bigint_print_hex(dest);
-       }
-#endif
-       bigint_mul_u(&tmp, &xl, &xh);
-#if DEBUG_SQUARE
-       if(square_depth == 1){
-           cli_putstr("\r\nDBG (4): xl*xh: "); bigint_print_hex(&tmp);
-       }
-#endif
-       bigint_shiftleft(&tmp, 1);
-#if DEBUG_SQUARE
-       if(square_depth == 1){
-           cli_putstr("\r\nDBG (5): xl*xh*2: "); bigint_print_hex(&tmp);
-       }
-#endif
-       bigint_add_scale_u(dest, &tmp, n * sizeof(bigint_word_t));
-#if DEBUG_SQUARE
-       if(square_depth == 1){
-           cli_putstr("\r\nDBG (6): x**2: "); bigint_print_hex(dest);
-           cli_putstr("\r\n");
-       }
-       square_depth -= 1;
-#endif
-}
-
-#endif
-
 /******************************************************************************/
 
 void bigint_square(bigint_t *dest, const bigint_t *a) {
@@ -697,7 +653,7 @@ void bigint_square(bigint_t *dest, const bigint_t *a) {
     bigint_word_t q, c1, c2;
     bigint_length_t i, j;
 
-    if(a->length_W * sizeof(bigint_word_t) <= 4){
+    if (a->length_W * sizeof(bigint_word_t) <= 4) {
         uint64_t r = 0;
         memcpy(&r, a->wordv, a->length_W * sizeof(bigint_word_t));
         r = r * r;
@@ -708,12 +664,13 @@ void bigint_square(bigint_t *dest, const bigint_t *a) {
         return;
     }
 
-    if(dest->wordv == a->wordv){
+    if (dest->wordv == a->wordv) {
         bigint_t d;
-        bigint_word_t d_b[a->length_W * 2];
-        d.wordv = d_b;
+        ALLOC_BIGINT_WORDS(d_w, a->length_W * 2);
+        d.wordv = d_w;
         bigint_square(&d, a);
         bigint_copy(dest, &d);
+        FREE(d_w);
         return;
     }
 
@@ -750,7 +707,6 @@ void bigint_square(bigint_t *dest, const bigint_t *a) {
 
 void bigint_sub_u_bitscale(bigint_t *a, const bigint_t *b, bigint_length_t bitscale){
        bigint_t tmp, x;
-       bigint_word_t tmp_b[b->length_W + 1];
        const bigint_length_t word_shift = bitscale / BIGINT_WORD_SIZE;
 
        if (a->length_W < b->length_W + word_shift) {
@@ -760,15 +716,17 @@ void bigint_sub_u_bitscale(bigint_t *a, const bigint_t *b, bigint_length_t bitsc
                bigint_set_zero(a);
                return;
        }
-       tmp.wordv = tmp_b;
+    ALLOC_BIGINT_WORDS(tmp_w, b->length_W + 1);
+       tmp.wordv = tmp_w;
        bigint_copy(&tmp, b);
-       bigint_shiftleft(&tmp, bitscale % BIGINT_WORD_SIZE);
+       bigint_shiftleft_bits(&tmp, bitscale % BIGINT_WORD_SIZE);
 
        x.info = a->info;
        x.wordv = &(a->wordv[word_shift]);
        x.length_W = a->length_W - word_shift;
 
        bigint_sub_u(&x, &x, &tmp);
+       FREE(tmp_w);
        bigint_adjust(a);
        return;
 }
@@ -813,15 +771,26 @@ void bigint_reduce(bigint_t *a, const bigint_t *r){
 /* calculate dest = a**exp % r */
 /* using square&multiply */
 void bigint_expmod_u_sam(bigint_t *dest, const bigint_t *a, const bigint_t *exp, const bigint_t *r){
-       if(a->length_W == 0){
+       if (a->length_W == 0) {
            bigint_set_zero(dest);
                return;
        }
 
-       bigint_t res, base;
-       bigint_word_t t, base_w[MAX(a->length_W, r->length_W)], res_w[r->length_W * 2];
+    if(exp->length_W == 0){
+        dest->info = 0;
+        dest->length_W = 1;
+        dest->wordv[0] = 1;
+        return;
+    }
+
+    bigint_t res, base;
+    bigint_word_t t;
        bigint_length_t i;
        uint8_t j;
+
+       ALLOC_BIGINT_WORDS(base_w, MAX(a->length_W, r->length_W));
+       ALLOC_BIGINT_WORDS(res_w, r->length_W * 2);
+
        res.wordv = res_w;
        base.wordv = base_w;
        bigint_copy(&base, a);
@@ -830,10 +799,6 @@ void bigint_expmod_u_sam(bigint_t *dest, const bigint_t *a, const bigint_t *exp,
        res.length_W = 1;
        res.info = 0;
        bigint_adjust(&res);
-       if(exp->length_W == 0){
-               bigint_copy(dest, &res);
-               return;
-       }
        bigint_copy(&res, &base);
        uint8_t flag = 0;
        t = exp->wordv[exp->length_W - 1];
@@ -858,6 +823,8 @@ void bigint_expmod_u_sam(bigint_t *dest, const bigint_t *a, const bigint_t *exp,
 
        SET_POS(&res);
        bigint_copy(dest, &res);
+       FREE(res_w);
+       FREE(base_w);
 }
 
 /******************************************************************************/
@@ -932,16 +899,17 @@ void bigint_gcdext(bigint_t *gcd, bigint_t *a, bigint_t *b, const bigint_t *x, c
         y_.length_W = y->length_W - i;
         memcpy(x_.wordv, x->wordv + i, x_.length_W * sizeof(bigint_word_t));
         memcpy(y_.wordv, y->wordv + i, y_.length_W * sizeof(bigint_word_t));
-        for(i = 0; (x_.wordv[0] & (1 << i)) == 0 && (y_.wordv[0] & (1 << i)) == 0; ++i){
-        }
+
+        for(i = 0; (x_.wordv[0] & ((bigint_word_t)1 << i)) == 0 && (y_.wordv[0] & ((bigint_word_t)1 << i)) == 0; ++i)
+            ;
 
         bigint_adjust(&x_);
         bigint_adjust(&y_);
 
         if(i){
-                bigint_shiftleft(&g, i);
-                bigint_shiftright(&x_, i);
-                bigint_shiftright(&y_, i);
+                bigint_shiftleft_bits(&g, i);
+                bigint_shiftright_bits(&x_, i);
+                bigint_shiftright_bits(&y_, i);
         }
 
         u.wordv = u_b;
@@ -963,22 +931,22 @@ void bigint_gcdext(bigint_t *gcd, bigint_t *a, bigint_t *b, const bigint_t *x, c
         bigint_set_zero(&c_);
         do {
                 while ((u.wordv[0] & 1) == 0) {
-                        bigint_shiftright(&u, 1);
+                        bigint_shiftright_1bit(&u);
                         if((a_.wordv[0] & 1) || (b_.wordv[0] & 1)){
                                 bigint_add_s(&a_, &a_, &y_);
                                 bigint_sub_s(&b_, &b_, &x_);
                         }
-                        bigint_shiftright(&a_, 1);
-                        bigint_shiftright(&b_, 1);
+                        bigint_shiftright_1bit(&a_);
+                        bigint_shiftright_1bit(&b_);
                 }
                 while ((v.wordv[0] & 1) == 0) {
-                    bigint_shiftright(&v, 1);
+                    bigint_shiftright_1bit(&v);
                         if((c_.wordv[0] & 1) || (d_.wordv[0] & 1)){
                                 bigint_add_s(&c_, &c_, &y_);
                                 bigint_sub_s(&d_, &d_, &x_);
                         }
-                        bigint_shiftright(&c_, 1);
-                        bigint_shiftright(&d_, 1);
+                        bigint_shiftright_1bit(&c_);
+                        bigint_shiftright_1bit(&d_);
                 }
                 if(bigint_cmp_u(&u, &v) >= 0){
                        bigint_sub_u(&u, &u, &v);
@@ -1014,9 +982,9 @@ void bigint_inverse(bigint_t *dest, const bigint_t *a, const bigint_t *m){
 
 void bigint_changeendianess(bigint_t *a){
        uint8_t t, *p, *q;
-       p = (uint8_t*)(a->wordv);
+       p = (uint8_t*)a->wordv;
        q = p + a->length_W * sizeof(bigint_word_t) - 1;
-       while(p<q){
+       while(p < q){
                t = *p;
                *p = *q;
                *q = t;
@@ -1067,13 +1035,15 @@ void bigint_clip(bigint_t *dest, bigint_length_t length_W){
 void bigint_mont_mul(bigint_t *dest, const bigint_t *a, const bigint_t *b, const bigint_t *m, const bigint_t *m_){
     const bigint_length_t s = MAX(MAX(a->length_W, b->length_W), m->length_W);
     bigint_t u, t;
-    bigint_word_t u_w[s + 2], t_w[s + 2];
+
     bigint_length_t i;
 
     if (a->length_W == 0 || b->length_W == 0) {
         bigint_set_zero(dest);
         return;
     }
+    ALLOC_BIGINT_WORDS(u_w, s + 2);
+    ALLOC_BIGINT_WORDS(t_w, s + 2);
     u.wordv = u_w;
     u.info = 0;
     u.length_W = 0;
@@ -1087,7 +1057,7 @@ void bigint_mont_mul(bigint_t *dest, const bigint_t *a, const bigint_t *b, const
             bigint_mul_word_u(&t, u.wordv[0]);
             bigint_add_u(&u, &u, &t);
         }
-        bigint_shiftright(&u, BIGINT_WORD_SIZE);
+        bigint_shiftright_1word(&u);
     }
     for (; i < s; ++i) {
         bigint_copy(&t, m_);
@@ -1095,25 +1065,29 @@ void bigint_mont_mul(bigint_t *dest, const bigint_t *a, const bigint_t *b, const
             bigint_mul_word_u(&t, u.wordv[0]);
             bigint_add_u(&u, &u, &t);
         }
-        bigint_shiftright(&u, BIGINT_WORD_SIZE);
+        bigint_shiftright_1word(&u);
     }
     bigint_reduce(&u, m);
     bigint_copy(dest, &u);
+    FREE(t_w);
+    FREE(u_w);
 }
 
 /******************************************************************************/
 
 void bigint_mont_red(bigint_t *dest, const bigint_t *a, const bigint_t *m, const bigint_t *m_){
     bigint_t u, t;
-    bigint_length_t i, s = MAX(a->length_W, m->length_W);
-    bigint_word_t u_w[s + 2], t_w[s + 2];
+    bigint_length_t i, s = MAX(a->length_W, MAX(m->length_W, m_->length_W));
 
-    t.wordv = t_w;
-    u.wordv = u_w;
     if (a->length_W == 0) {
         bigint_set_zero(dest);
         return;
     }
+
+    ALLOC_BIGINT_WORDS(u_w, s + 2);
+    ALLOC_BIGINT_WORDS(t_w, s + 2);
+    t.wordv = t_w;
+    u.wordv = u_w;
     bigint_copy(&u, a);
     for (i = 0; i < m->length_W; ++i) {
         bigint_copy(&t, m_);
@@ -1121,10 +1095,12 @@ void bigint_mont_red(bigint_t *dest, const bigint_t *a, const bigint_t *m, const
             bigint_mul_word_u(&t, u.wordv[0]);
             bigint_add_u(&u, &u, &t);
         }
-        bigint_shiftright(&u, BIGINT_WORD_SIZE);
+        bigint_shiftright_1word(&u);
     }
     bigint_reduce(&u, m);
     bigint_copy(dest, &u);
+    FREE(t_w);
+    FREE(u_w);
 }
 
 /******************************************************************************/
@@ -1134,20 +1110,17 @@ void bigint_mont_red(bigint_t *dest, const bigint_t *a, const bigint_t *m, const
 void bigint_mont_gen_m_(bigint_t* dest, const bigint_t* m){
     bigint_word_t x_w[2], m_w_0[1];
     bigint_t x, m_0;
-#if 0
-    printf("\nm = ");
-    bigint_print_hex(m);
-    uart0_flush();
-#endif
     if (m->length_W == 0) {
         bigint_set_zero(dest);
         return;
     }
     if ((m->wordv[0] & 1) == 0) {
+#if DEBUG
         printf_P(PSTR("ERROR: m must not be even, m = "));
         bigint_print_hex(m);
         putchar('\n');
         uart0_flush();
+#endif
         return;
     }
     x.wordv = x_w;
@@ -1161,27 +1134,11 @@ void bigint_mont_gen_m_(bigint_t* dest, const bigint_t* m){
     m_0.wordv[0] = m->wordv[0];
     bigint_adjust(&x);
     bigint_adjust(&m_0);
-#if 0
-    printf("\nm0 = ");
-    bigint_print_hex(&m_0);
-    printf("\nx = ");
-    bigint_print_hex(&x);
-    uart0_flush();
-#endif
     bigint_inverse(dest, &m_0, &x);
-#if 0
-    printf("\nm0^-1 = ");
-    bigint_print_hex(dest);
-    uart0_flush();
-#endif
     bigint_sub_s(&x, &x, dest);
-#if 0
-    printf("\n-m0^-1 = ");
-    bigint_print_hex(&x);
-    uart0_flush();
-#endif
     bigint_copy(dest, m);
     bigint_mul_word_u(dest, x.wordv[0]);
+
 }
 
 /******************************************************************************/
@@ -1191,8 +1148,8 @@ void bigint_mont_gen_m_(bigint_t* dest, const bigint_t* m){
  */
 void bigint_mont_trans(bigint_t *dest, const bigint_t *a, const bigint_t *m){
     bigint_t t;
-    bigint_word_t t_w[a->length_W + m->length_W];
 
+    ALLOC_BIGINT_WORDS(t_w, a->length_W + m->length_W);
     t.wordv = t_w;
     memset(t_w, 0, m->length_W * sizeof(bigint_word_t));
     memcpy(&t_w[m->length_W], a->wordv, a->length_W * sizeof(bigint_word_t));
@@ -1200,6 +1157,7 @@ void bigint_mont_trans(bigint_t *dest, const bigint_t *a, const bigint_t *m){
     t.length_W = a->length_W + m->length_W;
     bigint_reduce(&t, m);
     bigint_copy(dest, &t);
+    FREE(t_w);
 }
 
 /******************************************************************************/
@@ -1211,41 +1169,48 @@ void bigint_expmod_u_mont_accel(bigint_t *dest, const bigint_t *a, const bigint_
         return;
     }
 
-    bigint_length_t s = r->length_W;
     bigint_t res, ax;
-    bigint_word_t t, res_w[r->length_W * 2], ax_w[MAX(s, a->length_W)];
+    bigint_word_t t;
     bigint_length_t i;
     uint8_t j;
 
+    if (exp->length_W == 0) {
+        dest->length_W = 1;
+        dest->info = 0;
+        dest->wordv[0] = 1;
+        return;
+    }
+
+    ALLOC_BIGINT_WORDS(res_w, r->length_W * 2);
+    ALLOC_BIGINT_WORDS(ax_w, MAX(r->length_W, a->length_W));
+
     res.wordv = res_w;
     ax.wordv = ax_w;
 
     res.wordv[0] = 1;
     res.length_W = 1;
     res.info = 0;
-    bigint_adjust(&res);
-    if (exp->length_W == 0) {
-        bigint_copy(dest, &res);
-        return;
-    }
+
     bigint_copy(&ax, a);
     bigint_reduce(&ax, r);
+
     bigint_mont_trans(&ax, &ax, r);
     bigint_mont_trans(&res, &res, r);
+
     uint8_t flag = 0;
     t = exp->wordv[exp->length_W - 1];
     for (i = exp->length_W; i > 0; --i) {
         t = exp->wordv[i - 1];
         for(j = BIGINT_WORD_SIZE; j > 0; --j){
             if (!flag) {
-                if(t & (((bigint_wordplus_t)1) << (BIGINT_WORD_SIZE - 1))){
+                if(t & (((bigint_word_t)1) << (BIGINT_WORD_SIZE - 1))){
                     flag = 1;
                 }
             }
             if (flag) {
                 bigint_square(&res, &res);
                 bigint_mont_red(&res, &res, r, m_);
-                if (t & (((bigint_wordplus_t)1) << (BIGINT_WORD_SIZE - 1))) {
+                if (t & (((bigint_word_t)1) << (BIGINT_WORD_SIZE - 1))) {
                     bigint_mont_mul(&res, &res, &ax, r, m_);
                 }
             }
@@ -1254,6 +1219,8 @@ void bigint_expmod_u_mont_accel(bigint_t *dest, const bigint_t *a, const bigint_
     }
     SET_POS(&res);
     bigint_mont_red(dest, &res, r, m_);
+    FREE(ax_w);
+    FREE(res_w);
 }
 
 /******************************************************************************/
@@ -1278,7 +1245,15 @@ void bigint_expmod_u_mont_sam(bigint_t *dest, const bigint_t *a, const bigint_t
 #endif
 
 void bigint_expmod_u(bigint_t *dest, const bigint_t *a, const bigint_t *exp, const bigint_t *r){
-    if (r->wordv[0] & 1) {
+#if 0
+    printf("\nDBG: expmod_u (a ** e %% m) <%s %s %d>\n\ta: ", __FILE__, __func__, __LINE__);
+    bigint_print_hex(a);
+    printf("\n\te: ");
+    bigint_print_hex(exp);
+    printf("\n\tm: ");
+    bigint_print_hex(r);
+#endif
+    if (0 &&  r->wordv[0] & 1) {
         bigint_expmod_u_mont_sam(dest, a, exp, r);
     } else {
         bigint_expmod_u_sam(dest, a, exp, r);

diff --git a/bigint/bigint.h b/bigint/bigint.h
index 82e10f87054fbcfd8b0bc3083f303878a297b3c9..d07713dfacc5bec478d7ade48cc069fc63c0bef8 100644 (file)
--- a/bigint/bigint.h
+++ b/bigint/bigint.h
@@ -32,7 +32,7 @@
 #include <stdint.h>
 #include <limits.h>
 
-#define BIGINT_WORD_SIZE 8
+#define BIGINT_WORD_SIZE 32
 
 #if BIGINT_WORD_SIZE == 8
 typedef uint8_t  bigint_word_t;
@@ -80,7 +80,10 @@ int8_t bigint_cmp_u(const bigint_t * a, const bigint_t * b);
 void   bigint_add_s(bigint_t *dest, const bigint_t *a, const bigint_t *b);
 void   bigint_sub_s(bigint_t *dest, const bigint_t *a, const bigint_t *b);
 int8_t bigint_cmp_s(const bigint_t *a, const bigint_t *b);
+void   bigint_shiftleft_bits(bigint_t *a, uint8_t shift);
 void   bigint_shiftleft(bigint_t *a, bigint_length_t shift);
+void   bigint_shiftright_1bit(bigint_t *a);
+void   bigint_shiftright_1word(bigint_t *a);
 void   bigint_shiftright(bigint_t *a, bigint_length_t shift);
 void   bigint_xor(bigint_t *dest, const bigint_t *a);
 void   bigint_set_zero(bigint_t *a);

diff --git a/rsa/rsa_basic.c b/rsa/rsa_basic.c
index a7c321964aa86602605a392cf6535332a5eae099..345668e0bbcd5ca50769e4255cd606e2ed7cc11d 100644 (file)
--- a/rsa/rsa_basic.c
+++ b/rsa/rsa_basic.c
@@ -189,13 +189,12 @@ void rsa_os2ip(bigint_t *dest, const void *data, uint32_t length_B){
        uint8_t off;
        off = (sizeof(bigint_word_t) - length_B % sizeof(bigint_word_t)) % sizeof(bigint_word_t);
 #if DEBUG
-       cli_putstr_P(PSTR("\r\nDBG: off = 0x"));
-       cli_hexdump_byte(off);
+       printf("\r\nDBG: off = 0x%02x", off);
 #endif
-       if(!data){
-               if(off){
+       if (!data) {
+               if (off) {
                        dest->wordv = realloc(dest->wordv, length_B + sizeof(bigint_word_t) - off);
-                       memmove((uint8_t*)dest->wordv+off, dest->wordv, length_B);
+                       memmove((uint8_t*)dest->wordv + off, dest->wordv, length_B);
                        memset(dest->wordv, 0, off);
                }
        }else{
@@ -206,8 +205,7 @@ void rsa_os2ip(bigint_t *dest, const void *data, uint32_t length_B){
        }
        dest->length_W = (length_B + off) / sizeof(bigint_word_t);
 #if DEBUG
-       cli_putstr_P(PSTR("\r\nDBG: dest->length_W = 0x"));
-       cli_hexdump_rev(&(dest->length_W), 2);
+       printf("\r\nDBG: dest->length_W = %u", dest->length_W);
 #endif
 #endif
        dest->info = 0;

diff --git a/rsa/rsaes_pkcs1v15.c b/rsa/rsaes_pkcs1v15.c
index 4f41546de6dd420a4f7c369e75fc5e3ab834b18f..2825b81389150990479c741e31e395373facc1ff 100644 (file)
--- a/rsa/rsaes_pkcs1v15.c
+++ b/rsa/rsaes_pkcs1v15.c
@@ -79,7 +79,7 @@ uint8_t rsa_encrypt_pkcs1v15(void *dest, uint16_t *out_length, const void *src,
        cli_hexdump_block(x.wordv, x.length_W * sizeof(bigint_word_t), 4, 16);
 #endif
        bigint_adjust(&x);
-       rsa_os2ip(&x, NULL, length_B+pad_length+3);
+       rsa_os2ip(&x, NULL, length_B + pad_length + 3);
        rsa_enc(&x, key);
        rsa_i2osp(NULL, &x, out_length);
        return 0;

diff --git a/test_src/main-rsaes_pkcs1v15-test.c b/test_src/main-rsaes_pkcs1v15-test.c
index 8933b0227867e53d9a7788dfa7eb11f2be3a231e..1411b936ec045e65053bebdcde36be6ba467d8ed 100644 (file)
--- a/test_src/main-rsaes_pkcs1v15-test.c
+++ b/test_src/main-rsaes_pkcs1v15-test.c
@@ -588,11 +588,13 @@ void quick_test(void){
 
        cli_putstr_P(PSTR("\r\n\r\nciphertext:"));
        cli_hexdump_block(ciphertext, clen, 4, 16);
-       if(clen!=sizeof(ENCRYPTED)){
+       if(clen != sizeof(ENCRYPTED)){
                        cli_putstr_P(PSTR("\r\n>>FAIL (no size match)<<"));
+                       return;
        }else{
                if(memcmp_P(ciphertext, ENCRYPTED, clen)){
                        cli_putstr_P(PSTR("\r\n>>FAIL (no content match)<<"));
+                       return;
                }else{
                        cli_putstr_P(PSTR("\r\n>>OK<<"));
                }