I have written a win32 service socket server to listen for connections and do a little authentication (this is not a security question) and issue some commands.

I don't want to have to connect with any particular telnet client ala putty or CRT etc.. so it should work for native win32 telnet.exe as well as the others.

I ask for the username and password like so..(please, I know it's plain text.. I haven't got to that yet...)

                while ($new_remote = $sock->accept) {
                    $new_remote->autoflush(1);
                    print $new_remote "Welcome to MyListenSvc v$VERSIO
+N\r\n";
                    print $new_remote "Please enter your username: \r\
+n";
                    chomp ($usrname = <$new_remote>);
                    print $new_remote "Please enter your password: \r\
+n";
                    chomp ($password = <$new_remote>);
                    while (length($password) < 8) { 
                        print $new_remote "Password is too short.(Must
+ be at least 8 characters).\r\n";
                        print $new_remote "Please enter your password:
+ \r\n";
                        chomp ($password = <$new_remote>);
                    }
                    unless (&AuthUser($usrname, $password)) {
                        print $new_remote "Authentication Errors - Che
+ck your username and password.\n";
                        &Update_Log("... Login FAILED\n");
                        close ($new_remote);
                        last;
                    } else {
                        print $new_remote "Authenticated Successfully 
+";
                        print $new_remote "(Type help for a list of co
+mmands)\r\n";
                        print $new_remote "Command: ";
                        $sel->add($new_remote) if ($new_remote);
                        last;
                    }        
                }

[download]
The &AuthUser sub look like so
sub AuthUser
{
    my ($user, $pass) = @_;
    $user = substr($user, 0, -1);
    $pass = substr($pass, 0, -1);
    &Update_Log("Attempting to login as $usrname with $password... ");
    $auth_rc = 0;
    my $cipher = Crypt::CBC->new( { 'key'             => "$pass",
                                'cipher'          => 'Blowfish',
                                'iv'              => '$KJh#(}q',
                                'regenerate_key'  => 0,   # default tr
+ue
                                'padding'         => 'space',
                                'prepend_iv'      => 0
                           });
    
    my $ciphertext = $cipher->encrypt("$user");
                           
    open PWD, "C:/MyListenSvc/bin/passwd" or return ($auth_rc);
    
    while (<PWD>) {
        if (m#\Q$ciphertext\E#) {
            &Update_Log("... Login OK\n");
            $auth_rc = 1;
            last;
        }
    }
    close (PWD);
    return ($auth_rc);
}

[download]
The above code works but what concerns me is the 2 lines 
      $user = substr($user, 0, -1);
      $pass = substr($pass, 0, -1);

[download]
If I don't do this the authentication never works. When I printed the username and password to a log file I saw that a little square appears after the username and password.. I think it comes from the return that is entered. I tried to chomp the username and password but that never worked. So after beating my head for far too long I just tried to remove the last character...

Can anyone tell me why this happens and also if there is a better way to rectify this than what I have in the above code.

BTW. I havent tried to telnet from any *nix boxes yet..

-----
Of all the things I've lost in my life, its my mind I miss the most.

In reply to Extra Character from telnet by AcidHawk

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.