Diff: main.cpp

Revision:

2:a2a77f01dd26

Parent:

0:f83fc7ecf97b

--- a/main.cpp	Thu Sep 07 12:12:35 2017 +0000
+++ b/main.cpp	Wed Sep 13 09:24:51 2017 +0000
@@ -8,42 +8,77 @@
  *  Micro-ECC is optimized for ARM/ARM-thumb/ARM-thumb2/AVR platform
  *  Micro-ECC mbed version disabled thumb/thumb2 optimization because of its GCC syntax. 
  *      PS: I am not good at assembly for those projects.
+ *  Micro-ECC is highly sensitive to Random Number Generator, using two seperate ADC as input
  */
 
 #include "mbed.h"
 #include "uECC.h"
 
 Serial pc(USBTX, USBRX);
-AnalogIn rnd(A1);
+AnalogIn rnd1(A1);
+AnalogIn rnd2(A2);
+AnalogIn rnd3(A3);
+AnalogIn rnd4(A4);
+AnalogIn rnd5(A5);
+
 Timer t;
 
-void dumprand()
+//#define RNG_TEST 1
+#if defined(RNG_TEST)
+void randtest()
 {
     uint8_t buf[16];
     
-    pc.printf("plain_random:");
+    pc.printf("randtest():\r\n");
     for(int i=0; i<16; i++){
         buf[i] = rand();
         pc.printf("%02X",buf[i]);
     }
-    pc.printf("\r\n");
+}
+#endif
+
+void adctest()
+{
+        float buf[5];
+        buf[0] = rnd1.read()*3300;
+        buf[1] = rnd2.read()*3300;
+        buf[2] = rnd3.read()*3300;
+        buf[3] = rnd4.read()*3300;
+        buf[4] = rnd5.read()*3300;
+        pc.printf("adctest():\r\n");
+        for(int i=0; i<5; i++){
+            pc.printf("%.0f\t",buf[i]);
+        }
+        pc.printf("\r\n");
+}
+
+static int rawadc2int() {
+    uint8_t lsb;
+    uint8_t msb;
     
+    msb = uint8_t(rnd1.read()*3300);
+    lsb = uint8_t(rnd3.read()*3300);
+    return ((msb<<8)|lsb);
 }
-    
+
 static int RNG(uint8_t *dest, unsigned size) {
   // Use the least-significant bits from the ADC for an unconnected pin (or connected to a source of 
   // random noise). This can take a long time to generate random data if the result of analogRead(0) 
   // doesn't change very frequently.
-  pc.printf("Random:\r\n");
+  pc.printf("RNG():\r\n");
   while (size) {
     uint8_t val = 0;    
     for (unsigned i = 0; i < 8; ++i) {
       //int init = rnd.read();
-      int init = rand();
+      //int init = rand();
+            //int init = rnd1.read()*3300;
+            int init = rawadc2int();
       pc.printf("%04X",init);
       int count = 0;
       //while (rnd.read() == init) {
-      while (rand() == init) {  
+      //while (rand() == init) {  
+            //while((rnd1.read()*3300) == init){
+            while(rawadc2int() == init){
         ++count;
       }
       
@@ -85,39 +120,44 @@
   uint8_t secret1[20];
   uint8_t secret2[20];
 
+    memset(private1, 0, 21);
+    memset(private2, 0, 21);
+    memset(public1, 0, 40);
+    memset(public2, 0, 40);
+    memset(secret1, 0, 20);
+    memset(secret2, 0, 20);
+    
   pc.printf("Start ECC computation\r\n");
   pc.printf("make key 1\r\n");
   t.start();
   uECC_make_key(public1, private1, curve);
-  dumphex("public1: ", public1, sizeof(public1));
-  dumphex("private1: ", private1, sizeof(private1));
-  t.stop(); d = t.read_ms();
-  t.reset(); t.start();  
+  dumphex("public1:\r\n", public1, sizeof(public1));
+  dumphex("private1:\r\n", private1, sizeof(private1));
+  t.stop(); d = t.read_ms(); t.reset(); t.start();  
   pc.printf("time: %dms\r\n",d);
   
   pc.printf("make key 2\r\n");
   t.start();
   uECC_make_key(public2, private2, curve);
-  dumphex("public2: ", public2, sizeof(public2));
-  dumphex("private2: ", private2, sizeof(private2));
-  t.stop(); d = t.read_ms();
-  t.reset(); t.start();  
+  dumphex("public2:\r\n", public2, sizeof(public2));
+  dumphex("private2:\r\n", private2, sizeof(private2));
+  t.stop(); d = t.read_ms(); t.reset(); t.start();  
   pc.printf("time: %dms\r\n",d);
   
   pc.printf("make share secret 1\r\n");
   t.start();
   r = uECC_shared_secret(public2, private1, secret1, curve);
   pc.printf("r: %04X\r\n",r);
-  t.stop(); d = t.read_ms();
-  t.reset(); t.start();  
+    dumphex("secret1:\r\n", secret1, sizeof(secret1));
+  t.stop(); d = t.read_ms(); t.reset(); t.start();  
   pc.printf("time: %dms\r\n",d);
   
   pc.printf("make share secret 2\r\n");
   t.start();
   r = uECC_shared_secret(public1, private2, secret2, curve);
   pc.printf("r: %04X\r\n",r);
-  t.stop(); d = t.read_ms();
-  t.reset(); t.start();  
+    dumphex("secret2:\r\n", secret2, sizeof(secret2));
+  t.stop(); d = t.read_ms(); t.reset(); t.start();  
   pc.printf("time: %dms\r\n",d);
   
   pc.printf("\r\n\r\n");
@@ -126,13 +166,29 @@
 
 int main() {
     pc.baud(115200);
-    dumprand();
-    wait(1);
-    pc.printf("\r\n\r\nmicroECC test\r\n");
+      printf("\033[2J\033[0;0H");   // return to 0,0 and clear screen in VT100
+    pc.printf("\r\nmicroECC test\r\n");
+    
+#if defined(RNG_TEST)
+        // Test rand() functions is turly random.
+        for(int i=0; i<4; i++){
+            randtest();
+            pc.printf("\r\n");
+        }
+#endif
+        
+#if(0)      
+        for(int i=0; i<10; i++){
+            adctest();
+            wait(1);
+        }
+#endif      
     uECC_set_rng(&RNG);
     pc.printf("\r\n");
     
+    loop();
+    
     while(1) {
-        loop();
+        ;
     }
 }