asking for a password or code.

hey guys, what's the code that matlab program will ask for a password?if password is incorrect, the program will terminate. if it's correct the program will continue.

[Fangjun Jiang]

+1. I'd like to know if there is a way to implement it.

[Aaqib Khan]

function password()

X = inputdlg('PLEASE ENTER THE PASSWORD TO PROCEED');
x = str2double(X{1,1});
password = 123;             % SET IT HERE MANUALLY
if (x == password)
    uiwait(msgbox('Password Correct !!'));
else 

while (x ~= 123)
    if (x == password)
        uiwait(msgbox('Password Correct !!'));
        break;
    else
        uiwait(errordlg('Incorrect Password !!'));
        X = inputdlg('PLEASE ENTER THE PASSWORD TO PROCEED');
        x = str2double(X{1,1});
    end 
end
 uiwait(msgbox('Password Correct !!'));
end

[Matthew Cribb]

There is a flaw in this code. If you exit or cancel out in the passwork input dlgbx it will produce an error.

[Matthew Cribb]

%Use return to quit the function when exiting or canceling the inputdlg, 
%(i.e. when x is empty) i.e. put this right after the inputdlg..
if isempty(x) 
    return
end
%str2double() wnt wont work on emty cll array, so must not be...therefore
%this following evaulation of X wont occur if it is empty it is after the prev. 
% if isempty(x)-->return-->end 
 X = str2double(x{1,1});

[Pedro Rodriguez Alicea]

why cant i use this type of code for a gui?

i want to as soon as i run my gui get a pop up that requests a password

thank you!

Answer 1

[Jan]

There are some submissions in the FEX for a password input dialog:

• FEX: passwordUI
• FEX: login
• An example in FEX: 41 GUI examples
• FEX: getauthentication
• FEX: passwordentrydialog
• FEX: passcode

But the abortion of the program must be implemented by the user. If you distribute your program as M- or P-files, the protection level will be limited, see FEX: passprotect. Breaking this protection will take several minutes only. But at least the user needs a criminal intent to do this.

[Serge]

I wasn't hapy with eithe of those, so I made my own:

FEX: passwordtools

Answer 2

[Fangjun Jiang]

MATLAB doesn't have that function. You can use input() to ask the user to type in some numbers or letters. You have to do encryption yourself if you want to implement some type of password checking procedure.

The simplest way to do might be this. Ask the user to type in a password, compare it with a pre-defined one. The pre-defined one is stored in your source code (.m file). But you can use pcode() to convert your .m file to .p file. Since .p file is encrypted, you have some type of encryption protection. But it's not easy to implement a password changing functionality.

[Jan]

The functionality to change passwords is usually obtained by writing them encrypted to the disk. But the main problem is the limited protection level of P-coded files: Although you cannot convert them to M-code, you can use the debugger to inspect what's going on and catch calls to toolbox-function by shadowing them by local functions, e.g. "function R=strcmp(a,b), disp(a), disp(b), R=true", which will reveal the password very fast, if it is compare by STRCMP. SWITCH/CASE is one of the few possibilities to compare a password without using a shadowable built-in function.

[Walter Roberson]

You could use one-way hashing, like Unix does.

Answer 3

[Walter Roberson]

See http://blogs.mathworks.com/pick/2007/10/05/masking-typed-passwords-with-asterisks/

Answer 4

[Oleg Komarov]

An addition to the list by Jan FEX: passfield.

Answer 5

[sonali mishra]

how to make the password hide?? and i also want to make a userID box with this password box... can u help me how to create these.....

[Walter Roberson]

Several of the file exchange contributions listed in the above responses hide the answer.