Found cryptography library that was very easy to install.

Have hashing and verification functs ready.

CMakeLists.txt

@@ -19,6 +19,8 @@ add_executable(park
         headers/Park_spot.h
         Park_time.cpp
         headers/Park_time.h
+        encrypt.cpp
+        headers/encrypt.h
  )
 
 
@@ -30,6 +32,7 @@ if (UNIX)
         sqlite3
         pthread
         dl 
+        libsodium
         )
 elseif (MSYS OR MINGW) 
         target_link_libraries(park
@@ -37,6 +40,7 @@ elseif (MSYS OR MINGW)
         sqlite3
         pthread
         ssp 
+        libsodium
         )
 endif()
 

data.cpp

@@ -6,7 +6,9 @@ SQLite::Database
 start_db() {
     SQLite::Database db("test.db3",
                         SQLite::OPEN_READWRITE | SQLite::OPEN_CREATE);
-
+    while (sodium_init()< 0){
+        std::cout << "SODIUM NOT WORKING";
+    }
     db.exec(
         "create table if not exists Customer (id integer primary key, name "
         "text, card_code varchar(20), verhicle int)");

encrypt.cpp

@@ -0,0 +1,35 @@
+#include "headers/encrypt.h"
+
+
+string hash_password(string password) {
+    /*
+    Passing strings and converting to char* because I do not want to be forced
+    to use char * whenever I want to call the function. Low level stuff in the
+    function, the least possible low level stuff outside.
+     */
+    const char* password_ = password.c_str();
+    char hashed_password_[crypto_pwhash_STRBYTES];
+    int memory_limit = 1.28e+8; // 1.28 e+8 = 128 e6 = 128 mb
+    int cpu_limit = 2;          // this is n_threads
+
+    int result = crypto_pwhash_str(hashed_password_,
+                                   password_,
+                                   strlen(password_),
+                                   cpu_limit,
+                                   memory_limit);
+    string hashed_password{hashed_password_};
+
+    return hashed_password;
+}
+
+bool verify_password(string hashed_password, string unhashed_password) {
+    const char* password_ = unhashed_password.c_str();
+    const char* hashed_password_ = hashed_password.c_str();
+
+    if (crypto_pwhash_str_verify(
+            hashed_password_, password_, strlen(password_)) != 0) {
+        return false;
+    } else {
+        return true;
+    }
+}

headers/data.h

@@ -2,6 +2,8 @@
 #define DATA_H
 #pragma once
 #include "../thirdparty/SQLiteCpp/include/SQLiteCpp/SQLiteCpp.h"
+#include "encrypt.h"
+
 namespace data {
 SQLite::Database
 start_db();

headers/encrypt.h

@@ -0,0 +1,15 @@
+#ifndef ENCRYPT_H
+#define ENCRYPT_H
+#pragma once
+
+#include <string>
+#include <cstring>
+#include <sodium.h>
+#include <iostream>
+
+using std::string;
+
+string hash_password(string password);
+bool verify_password(string hashed_password, string unhashed_password);
+
+#endif

main.cpp

@@ -2,6 +2,7 @@
 
 #include <thread>
 
+
 /*
 Code strucure like this:
 class declarations zijn in /headers/class_naam.h, en definitions van de member
@@ -17,8 +18,7 @@ record die zegt dat een customer voor x tijd geparkeert heeft bij spot x, enz.
 De client clockt in en uit bij een spot.
  */
 
-void
-Wait(int sec)
+void Wait(int sec)
 /*
 a wait function where 1 sec represents 1 hour irl.
  */
@@ -26,14 +26,22 @@ a wait function where 1 sec represents 1 hour irl.
     std::this_thread::sleep_for(seconds{sec});
 }
 
-int
-main() {
+int main() {
     class Customer sagar {
         "Sagar Ramsaransing", Verhicle_type::bike
     };
     sagar.update_db();
     Park_spot p1;
     p1.clock(&sagar);
-    Wait(2);
+    // Wait(2);
     // p1.clock(&sagar);
+    string a = hash_password("test");
+    string b = hash_password("test");
+    string c = hash_password("test");
+    string d = hash_password("tast");
+    cout << a << "\n" << b << "\n" << c << "\n";
+    cout << verify_password(a, "test") << "," 
+         << verify_password(b, "test") << ", " 
+         << verify_password(c, "test") << ", " 
+         << verify_password(d, "test");
 }