Little speed up

Author: beranm14

Arduino_ECCDH/ECDH.cpp

@@ -158,12 +158,12 @@ inline void addfromto(unsigned char * a, unsigned char * b, unsigned char from,
         a[i] = a[i] ^ b[i - from];
     }
 }
-
-inline unsigned char * mul(unsigned char * a, unsigned char * b, unsigned char * res){ //corrected
+inline unsigned char * mul(unsigned char * a, unsigned char * b, unsigned char * res){ // changed
     //unsigned char res[SIZE];
-    cleanPoly(res);
+
     unsigned char tmpa[SIZE];
     copyPoly(tmpa, a);
+    cleanPoly(res);
     unsigned char j = 0x01;
     for(unsigned char k = 0; k < 8; k++){
         for(unsigned char i = 0; i < SIZE; i++){
@@ -289,43 +289,55 @@ unsigned char isBiggerThanOne(unsigned char * b){ // corrected
     return true;*/
 }
 
+void doperm( unsigned char *tmp_a, unsigned char * tmp_b, unsigned char * tmp, unsigned char * q, unsigned char * t, unsigned char * x0, unsigned char * x1, unsigned char * restmp, unsigned char * res){
+     while (isBiggerThanOne(tmp_a)) {
+        //cleanPoly(tmp);
+        cleanPoly(q);
+        divMod(tmp_a, tmp_b, tmp, q);// q = a / b;
+
+        copyPoly(tmp_a, tmp_b); // a = t;
+        copyPoly(tmp_b, tmp);// b = tmp;
+        copyPoly(t, x0); //t = x0;
+        //cleanPoly(restmp);
+        //cleanPoly(restmp);
+        mul(x0, q, x0);
+        //x0 = restmp;
+        add(x0, x1);
+        //copyPoly(x0, restmp); // x0 = x1 + q * x0;
+        //x0 = x1;
+        //(unsigned char*)x0 = (unsigned char*)add(x1, mul(q, x0, restmp));
+        copyPoly(x1, t); //x1 = t;
+        //x1 = p;
+    }
+    copyPoly(res, x1);
+}
 
-void inverse(unsigned char * a, unsigned char * b, unsigned char * res){
+inline void inverse(unsigned char * a, unsigned char * b, unsigned char * res){
     unsigned char tmp_a[SIZE];
     copyPoly(tmp_a, a);
     unsigned char tmp_b[SIZE];
     copyPoly(tmp_b, b);
 
-  unsigned char b0[SIZE], t[SIZE], q[SIZE];
-    copyPoly(b0,b);
+  unsigned char t[SIZE];
+  unsigned char q[SIZE];
+    //copyPoly(b0,b);
     cleanPoly(q);
-    unsigned char x0[SIZE], x1[SIZE];
+    unsigned char x0[SIZE];
+    unsigned char x1[SIZE];
+    //unsigned char * x1 = NULL;
     cleanPoly(x0);
     x0[0] = 0x01;
     cleanPoly(x1);
+    unsigned char restmp[SIZE];
+    unsigned char tmp[SIZE];
 
-  if (isOne(b)) return;
-  while (isBiggerThanOne(a)) {
-        unsigned char tmp[SIZE];
-        cleanPoly(tmp);
-        cleanPoly(q);
-        divMod(a, b, tmp, q);// q = a / b;
-        copyPoly(t, b);// t = b;
-        copyPoly(b, tmp);// b = tmp;
-        copyPoly(a, t); // a = t;
-    copyPoly(t, x0); //t = x0;
-        unsigned char restmp[SIZE];
-        cleanPoly(restmp);
-        copyPoly(x0, add(x1, mul(q, x0, restmp))); // x0 = x1 + q * x0;
-    copyPoly(x1, t); //x1 = t;
-    }
-  copyPoly(res, x1);
-  copyPoly(a,tmp_a);
-    copyPoly(b,tmp_b);
+  if (isOne(tmp_b)) return;
+  doperm(tmp_a, tmp_b, tmp, q, t, x0, x1, restmp, res);
+  //copyPoly(a,tmp_a);
+    //copyPoly(b,tmp_b);
 }
 
 
-
 unsigned char * mulRed(unsigned char * a, unsigned char * b, unsigned char * result){
         mul(a, b, result);
         reduce(result);

Arduino_ECCDH/ECDH.h

@@ -34,6 +34,8 @@ unsigned char * getPoly(unsigned int a, unsigned char * poly);
 
 void divMod(unsigned char * a, unsigned char * b, unsigned char * m, unsigned char * d);
 
+void doperm( unsigned char *tmp_a, unsigned char * tmp_b, unsigned char * tmp, unsigned char * q, unsigned char * t, unsigned char * x0, unsigned char * x1, unsigned char * restmp, unsigned char * res);
+
  unsigned char isOne(unsigned char * b);
 
 unsigned char * reduce(unsigned char * c);

PC_ECC/main.cpp

@@ -547,9 +547,10 @@ inline void addfromto(unsigned char * a, unsigned char * b, unsigned char from,
 
 inline unsigned char * mul(unsigned char * a, unsigned char * b, unsigned char * res){ // changed
     //unsigned char res[SIZE];
-    cleanPoly(res);
+
     unsigned char tmpa[SIZE];
     copyPoly(tmpa, a);
+    cleanPoly(res);
     unsigned char j = 0x01;
     for(unsigned char k = 0; k < 8; k++){
         for(unsigned char i = 0; i < SIZE; i++){
@@ -564,6 +565,7 @@ inline unsigned char * mul(unsigned char * a, unsigned char * b, unsigned char *
 }
 
 
+
 inline unsigned char * getPoly(unsigned int a, unsigned char * poly){ // changed
     unsigned int where = a / 8;
     unsigned int which = a % 8;
@@ -692,24 +694,26 @@ inline unsigned char isEqualPoly(unsigned char * a, unsigned char * b){
 }
 
 void doperm( unsigned char *tmp_a, unsigned char * tmp_b, unsigned char * tmp, unsigned char * q, unsigned char * t, unsigned char * x0, unsigned char * x1, unsigned char * restmp, unsigned char * res){
-    while (isBiggerThanOne(tmp_a)) {
+     while (isBiggerThanOne(tmp_a)) {
         //cleanPoly(tmp);
         cleanPoly(q);
         divMod(tmp_a, tmp_b, tmp, q);// q = a / b;
-        copyPoly(t, tmp_b);// t = b;
+
+        copyPoly(tmp_a, tmp_b); // a = t;
         copyPoly(tmp_b, tmp);// b = tmp;
-        copyPoly(tmp_a, t); // a = t;
         copyPoly(t, x0); //t = x0;
         //cleanPoly(restmp);
-        mul(q, x0, restmp);
-        add(x1, restmp);
-        copyPoly(x0, x1); // x0 = x1 + q * x0;
+        //cleanPoly(restmp);
+        mul(x0, q, x0);
+        //x0 = restmp;
+        add(x0, x1);
+        //copyPoly(x0, restmp); // x0 = x1 + q * x0;
         //x0 = x1;
         //(unsigned char*)x0 = (unsigned char*)add(x1, mul(q, x0, restmp));
-		copyPoly(x1, t); //x1 = t;
-		//x1 = p;
+        copyPoly(x1, t); //x1 = t;
+        //x1 = p;
     }
-	copyPoly(res, x1);
+    copyPoly(res, x1);
 }
 
 inline void inverse(unsigned char * a, unsigned char * b, unsigned char * res){
@@ -1034,7 +1038,7 @@ int main(int argc, char *argv[])
 */
 
 
-    if(argc < 2){
+   if(argc < 2){
         cout << "None port given" << endl;
         return 1;
     }