The code where you retrieve your form parameters should like something like this: 

my $user_name = $cgi_object->param('user_name'} || '';
my $passwd = $cgi_object->param('passwd') || '';
unless ($user_name && $passwd) {
# handle cgi param error
}

[download]

The database query needs to use a placeholder, and check for errors - something like this: 

eval {
  $sth = $dbh->prepare("select pass from users where user=?");
  $sth->execute($user_name);
};
if ($@) {
# handle database error
}

[download]

Since HTML is stateless, you need to use something like CGI::Session to remember that a particular user is logged in.

Using a framework will make your life much easier. Here's a link to a simple login tutorial I wrote:
RFC: Proposed tutorial - simple login script using CGI::Application

That should help get you started.

In reply to Re: Login Script by scorpio17
in thread Login Script by ironside

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