user data security

Let me point out some errors:

char USERNAME[11] = "miniproject";

 error C2117: 'USERNAME' : array bounds overflow

char PASSWORD[10] = "qwert!@#$%";

error C2117: 'PASSWORD' : array bounds overflow

Please remember that string are terminated with '\0' so you need to define the length one longer.
Also it would be better to use a type of constant for the length like

1
2

#define USER_LEN  12
#define PW_LEN     12

Next errors are:

1
2

if(sizeof(username) < 11)
if(sizeof(password) < 10)

sizeof gives you the len of the var, not the len of the input - to get the len of the input you need the function strlen()

if(username == USERNAME && password == PASSWORD)

to compare strings you need the function strcmp() or stricmp()

Hope this helps.

@Thomas1966

If I'm using any function like strcmp() or stricmp() in turbo c++, it is showing error as "strcmp() should have a prototype" and same error in stricmp also.

and also, program is never getting inside if condition, either it is not comparing the strings and directly displaying the switch case otherwise, it is getting inside else loop every time

You need to include <string.h> to use strcmp() or stricmp(). Could you post the code again once you have done it. There might be other errors as well.

oh, thank you Thomas1965, the errors are removed and the login part is working well now.

but the load a new file method is not working as it should work.

this is my complete program

#include <iostream.h>
#include <stdio.h>
#include <string.h>
#include <conio.h>
#include <fstream.h>




void lockfolder();

int main()
{


	int i,a=0,count=0;
	char c,fname[10], mycode[12]="grantaccess";
	char user[12] = "miniproject";
	char pass[11] = "qwert!@#$%";
	unsigned int choice=0, lock, yes, code;

	char username[11], password[10];
	cout << "\n\t\t\t\t\tWelcome to our Security System..!!!" << endl;

	while(count<3)

	{

	cout << "\n\t\t\t\t\tUsername :: ";
	cin >> username;

	cout << "\n\t\t\t\t\tPassword :: ";
	cin >> password;

	if(strlen(username) < 11)
		{
			cout << "\n\t\t\t\t\tnot proper username";
			count++;
		}

	if(strlen(password) < 10)
		{
			cout << "\n\t\t\t\t\tpassword not proper";
			count++;
		}

	if(strcmp(username, user)==0 && strcmp(password, pass)==0)
		{



				cout << "\n\n\t\t\t\t\t\tLogin Successful" << endl;
				cout << "\t\t\t\t\t\t\t-------------------\n\n" << endl;
				cout << "\n\n\t\t\t\t\t\t --=Welcome to the software=--" << endl;
				cout << "\t\t\t\t\t\t=================================\n\n\n" << endl;
				count=3;


				do
				{


				switch(a)

				{


			case 0:
			{


			cout << "Available commands:\n\n";
			cout << "0. list commands\n\n";
			cout << "1. write a new file\n\n";
			cout << "2. load a file\n\n";
			cout << "3. exit program\n\n";

			break;

			}



				case 1:
				{

					ofstream out;
			cout<<"Enter File name:";
			cin>>fname;
			out.open(fname);

					cout<<"Enter contents to store in file (Enter # at end):\n";
			while((c=getchar())!='#')
			{

			    out<<c;

					}
					cout<<"want to lock this file? press 1 else press 2 :: ";
					cin>>choice;

					if(choice==1)
					{

					lock=1;

					}

					else
					{

						cout<<"quitting...";

					}


			out.close();

				}

				case 2:
				{
					cout<<"enter file name to open ";
					cin>>fname;
					if(lock==1)
					{

					cout<<"sorry..this file is locked.\n Want to unlock? press 1 ";
					cin>>yes;

					if(yes==1)
					{

					cout<<"enter unlock code ";
					cin>>code;

					if(code==mycode[12])
					{

					lock=0;

					}
					else

					cout<<"wrong code";

					return 0;

					}
					else

					return 0;
					}

					char line[1000];
					cout<<"Enter File name: ";
					cin>>fname;
					ifstream myfile(fname);

					while (myfile.eof())
					{




					cout << line << '\n';



					myfile.close();

					}



				}

				case 3:
				{

				 cout<< "\n\nTHANK YOU FOR USING THIS SOFTWARE...";


				}


				default:

					cout << "\n\nUnrecognized command. Enter '0' to view command list\n";


			}


			cout << "\nEnter command:";
		cin >> a;

	}

	while (a!=3);
		}


			else
			{

				cout << "\n\t\t\t\t\tInvalid login details. Please try again"
				<< endl;
				count++;

			}

		}
	 return 0;
	}

The logic of your code would be much easier to follow - for you and us - if you adopted a sensible indentation policy.

Also, do you really think

not working as it should work

is a helpful description? How is it working? How does that differ from how it should work? Help us to help you.

        case 2:
        {
          cout<<"enter file name to open ";
          cin>>fname;
          if(lock==1)
          {
            cout<<"sorry..this file is locked.\n Want to unlock? press 1 ";
            cin>>yes;

            if(yes==1)
            {
              cout<<"enter unlock code ";
              cin>>code;

              if(code==mycode[12])
              {
                lock=0;
              }
              else
                cout<<"wrong code";

              return 0;
            }
            else
              return 0;
          }

          char line[1000];
          cout<<"Enter File name: ";
          cin>>fname;
          ifstream myfile(fname);

          while (myfile.eof())
          {
            cout << line << '\n';
            myfile.close();
          }
        }

EDIT: One thing that becomes easier to see with a sensible layout, is that if the file is locked, the function will exit without opening and reading the file, regardless of whether the user enters 1 or not.

Last edited on

sorry that's my fault @MikeyBoy

actually, i want it to read and write files after user login (successful login) and also to hide data written in files if user wants i.e. after complete writing of file, if user want to encrypt the data then he could.

and if in case user fails to login correctly for consecutively 3 times, it must encrypt ll the files written via this program should get encrypted and decryption will be done after verification.

presently, it is doing the login process successfully and even writing the file as required but while it comes to load any file, the process terminates (even the file is not locked) and the available commands list is displayed again and it asks for user to input command to weather to write or load a file or to exit the program.

and talking about locking of any file, once the programs exits and you starts it again, lock value again gets to 0 i.e. all locked files are unlocked now, tough, later on, i will not use this lock method instead i will ask user to encrypt the file or not.

So what actually happens when the user selects "2" in the main menu?

Do you see the prompt:

enter file name to open

or any of the other expected prompts?

Last edited on

ya, it do show this message

enter file name to open

but actually, when I'm giving input as 1, it is writing file and after saving the file as per the given name, case 2 and case 3 are automatically starting and all the cout << "" are displayed by default

if user select 1, case 2 and 3 also gets starts after case 1 ends and if user selects 2, case 3 starts after ending case 2, the similar process is continuing

Oh, that's because you've forgotten to put break statements at the end of each case.

ya, it's fine now but why this part of code is not working?


char line[1000];
cout<<"Enter File name: ";
cin>>fname;
ifstream myfile(fname);
while (myfile.eof())
{
cout << line << '\n';
myfile.close();
}

It must be !myfile.eof() otherwise it will never be true.

it's not working even if !myfile.eof() is used.

after this command !myfile.eof() if I try to load any file, a blank black screen is displayed and turbo c++ gets hang.

cout << line << '\n';

you need to get the input into line otherwise it is empty.

but I'm doing the same I guess

and also this code is working well in Dev C++, but not in Turbo C++

Do I understand right that you just want to display the file?

If yes you can do it like this;

string input;
ifstream myfile(fname);
while (myfile >> input)
{
   cout << input << '\n';
}

but I'm doing the same I guess

You're not reading what Thomas is telling you:

you need to get the input into line otherwise it is empty.

Nowhere in your code do you store anything in line. line is a completely empty char array.

Last edited on