D main.cpp

@@ -1,61 +0,0 @@ 
-#include <fstream>
-#include <chrono>
-#include <cstring>
-
-char base16[] = "0123456789ABCDEF";
-
-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 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 = std::rand();
-            for (j = 0; j < 4; j++) {
-                bytes[i + j] = r & 255;
-                r >>= 8;
-            }
-        }
-    }
-};
-
-struct otp {
-
-};
-
-int main() {
-    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("%u ", secret.bytes[i]);
-    }
-    s = secret.encode();
-    printf("\n%s\n", s);
-
-    return 0;
-}

A otpp.h

@@ -0,0 +1,58 @@ 
+#include <fstream>
+#include <chrono>
+#include <cstring>
+#include <functional>
+
+const static char base16[] = "0123456789ABCDEF";
+
+struct OTP {
+    unsigned char bytes[16];
+
+    char* exportSecret() {
+        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 importSecret(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 generateNewSecret() {
+        std::srand(std::chrono::high_resolution_clock::now().time_since_epoch().count());
+        int r, i, j;
+        for (i = 0; i < 16; i += 4) {
+            r = std::rand();
+            for (j = 0; j < 4; j++) {
+                bytes[i + j] = r & 255;
+                r >>= 8;
+            }
+        }
+    }
+
+     int currentToken(int validDuration = 30) {
+        int trunc = time(nullptr);
+        trunc = trunc - (trunc % validDuration);
+        unsigned char b[20];
+        int i = 0;
+        for (; i < 16; i++) b[i] = bytes[i];
+        for (; i < 20; i++) {
+            b[i] = trunc & 255;
+            trunc >>= 8;
+        }
+        unsigned long hash = std::hash<std::string>{}(std::string((char*)b, 20));
+        int token = 0;
+        for (;token < 100000;) {
+            token = hash % 1000000;
+            hash >>= 20;
+        }
+        return token;
+    }
+};