Storing passwords while keeping the integrity of getch() - c++

Question

Whats an easy way I can store the password the user inputs while still keeping the password hidden?
char password[9];
int i;
printf("Enter your password: ");
for (i=0;i<9;i++)
{
password[i] = getch();
printf("*");
}
for (i=0;i<9;i++)
printf("%c",password[i]);
getch();
}
I wanna store the password so I can do a simple if (password[i] == root_password) so the proper password continues on.

Answer 1

Your problem appears to be that you're not checking for newline '\n' nor end-of-file.
printf("Enter your password: ");
char password[9];
int i;
for (i = 0; i < sizeof password - 1; i++)
{
int c = getch();
if (c == '\n' || c == EOF)
break;
}
password[i] = c;
printf("*");
}
password[i] = '\0';
This way, password will end up being an ASCIIZ string, suitable for printing with puts, printf("%s", password), or - crucially...
if (strcmp(password, root_password)) == 0)
your_wish_is_my_command();
Note that we read at most 8 characters into the password as we need one extra character for the NUL terminator. You could increase that if you wanted.

Answer 2

You need to use the console API in Windows. Below is a snippet that disables echoing in the console window. The function SetConsoleMode() is used to control the echoing (among other things). I save the old mode, so that I can restore the console once the password has been retrieved.
Also, the *ConsoleMode() functions need a handle to the console input buffer. How you can get a handle to these buffers is described in the MSDN documentation of CreateFile().
int main(int argc, char* argv[])
{
char password[100] = { 0 };
printf("Enter your password: ");
HANDLE hConsole = ::CreateFile("CONIN$", GENERIC_WRITE | GENERIC_READ, FILE_SHARE_READ, 0, OPEN_EXISTING, 0, 0);
DWORD dwOldMode;
::GetConsoleMode(hConsole, &dwOldMode);
::SetConsoleMode(hConsole, dwOldMode & ~ENABLE_ECHO_INPUT);
bool bFinished = false;
while(!bFinished) {
if(!fgets(password, sizeof(password) / sizeof(password[0]) - 1, stdin)) {
printf("\nEOF - exiting\n");
} else
bFinished = true;
}
::SetConsoleMode(hConsole, dwOldMode | ENABLE_ECHO_INPUT);
printf("\nPassword is: %s\n", password);
return 0;
}

Answer 3

Since we are in C++ and Windows do this:
#include <iostream>
#include <string>
#include <conio.h> //_getch
#include <Windows.h> //VK_RETURN = 0x0D
using namespace std;
string read_password()
{
string pass;
cout << "Enter your password: ";
int character = 0;
while(VK_RETURN != (character = _getch()) )
{
cout << '*';
pass += static_cast<char>(character);
}
cout << std::endl;
return pass;
}
int main ()
{
string root_password = "anypass123";
string pass = read_password();
if (pass == root_password)
{
cout << "password accepted" << endl;
}
return 0;
}
compiled & tested