M main.cpp → main.cpp

@@ -1,26 +1,46 @@ 
 #include <fstream>
+#include <chrono>
+#include <cstring>
 
-const char* chars16 = "0123456789ABCDEF";
+char base16[] = "0123456789ABCDEF";
 
-struct secret {
-    char bytes[16];
+struct Secret {
+    unsigned char bytes[16];
+
+    char* encode() {
+        static char s[33];
+        for (int i = 0; i < 16; i++) {
+            s[i*2] = base16[(bytes[i] >> 4) & 15];
+            s[i*2+1] = base16[bytes[i] & 15];
+        }
+        s[32] = '\0';
+        return s;
+    }
+
+    void decode(char* s){
+        for(int i = 0; i < 16; i++) {
+            bytes[i] = ((strchr(base16, s[i*2]) - base16) << 4)
+                    | (strchr(base16, s[i*2+1]) - base16);
+        }
+    }
 
     void load(char* file) {
         FILE* f = fopen(file, "r");
-        fread(secret, 1, 16, f);
+        fread(bytes, 1, 16, f);
         fclose(f);
     }
 
     void save(char* file) {
         FILE* f = fopen(file, "w");
-        fwrite(secret, 1, 16, f);
+        fwrite(bytes, 1, 16, f);
         fclose(f);
     }
 
     void generate() {
+        std::srand(std::chrono::high_resolution_clock::now().time_since_epoch().count());
         int r, i, j;
         for (i = 0; i < 16; i += 4) {
-            r = rand();
+            r = std::rand();
             for (j = 0; j < 4; j++) {
                 bytes[i + j] = r & 255;
                 r >>= 8;
@@ -29,14 +49,25 @@ }
     }
 };
 
-stuct otp {
+struct otp {
 
 };
 
 int main() {
-    secret s;
-    s.generate();
+    Secret secret;
+
+    secret.generate();
+    for (int i = 0; i < 16; i++) {
+        printf("%u ", secret.bytes[i]);
+    }
+    char* s = secret.encode();
+    printf("\n%s\n", s);
+    secret.decode(s);
     for (int i = 0; i < 16; i++) {
-        printf("%c%c", chars16[s.bytes[i] >> 4], chars16[s.bytes[i] & 15]);
+        printf("%u ", secret.bytes[i]);
     }
+    s = secret.encode();
+    printf("\n%s\n", s);
+
+    return 0;
 }