I'm learning perl, and I'm currently trying to write a user login system. I have the following code in login.pl: 
# !perl

use CGI qw(:standard);                # use the CGI libraries 
print header;                    # start the html output

$username = param('username');            # take <input name=username>
$password = param('password');            # take <input name=password>
+ 

open(FILE, "./users/$username");        # open the user's file in $use
+rs
$passhash = <FILE>;                # read the password hash from the f
+ile
close(FILE);                    # close the file

if (crypt($password, $passhash) eq $passhash) {
     print "You are now logged in.";
} else {
    print "Incorrect username or password, please try again.";
}

[download]
$passhash was written to a file with the user's name earlier on (in newuser.pl): 
$salt = join '', ('.', '/', 0..9, 'A'..'Z', 'a'..'z') [rand 64, rand 6
+4];
                        # create random two-character salt

$passhash = crypt($password, $salt);        # hash the password with t
+he salt

[download]
My question is: how can I set it so that the user can stay logged in between pages (eg. use a cookie) without storing the password somewhere in plaintext to check $passhash against? Sorry if I've gone about this whole thing completely the wrong way.

In reply to setting a cookie on login by reklaw

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