#!/usr/local/bin/perl

# afm.cgi - Any Form Mailer v1.0
# (c)1998 Bernhard Tischler <mailto:bernd666@hotmail.com>
#                           <URL:http://foo.VirtualAve.net>
#
# This script may be used and modified free of charge by anyone so
# long as all copyright notices remain intact. If you think, that you
# have made a real improvement to this script, than email me.
#
# Selling the code for this program without prior written consent is
# expressly forbidden. In other words, please ask first before you
# try and make money of my program.
#
# Obtain permission before redistributing this software over the
# Internet or in any other medium. In all cases copyright and header
# must remain intact.
#
# Script setup:
# -------------
#
# Change the first line of this file, if necessary. Either
# '#!/usr/local/bin/perl' or '#!/usr/bin/perl' should work on any unix
# system.
# Change the configuration part below as described below.
# Upload this file as ASCII to your cgi-bin and chmod it to 755, if
# you have a unix server.
# ( owner:    [x]read [x]write [x]execute
#   group:    [x]read [ ]write [x]execute
#   everyone: [x]read [ ]write [x]execute )
#
# Form setup:
# -----------
#
#   Required fields:
#
# <FORM METHOD="POST" ACTION="/cgi-bin/afm.cgi">
# <INPUT TYPE="hidden" NAME="to" VALUE="alias">
# The first line is the location of the mail script. The second line is the alias
# of the recipient as specified in %alias (see cofiguration below).
#
# All other fields are optional, but i guess it would be a good idea to include
# some. :)
#
#   Configuration fields:
#
# - linkURL
# This will be used for a link on the confirmation page. Default is
# your base directory /. Example:
# <INPUT TYPE="hidden" NAME="linkURL" VALUE="http://your.server.com/you/index.html">
#
# - linkName
# This will be used as name for the link specified above. Default is 'home'.
# Example: <INPUT TYPE="hidden" NAME="linkName" VALUE="home">
#
# - e-mail:
# The email address of your visitor. This will appear in the 'From' field of the
# messages header. Example: <INPUT TYPE="text" NAME="e-mail">
#
# - name
# The realname of your visitor. This will appear in the 'From' field of the
# messages header. Example: <INPUT TYPE="text" NAME="name">
#
# - subject
# The subject of the message. This will appear in the 'Subject' field of the
# messages header. Example: <INPUT TYPE="text" NAME="subject">
#
# - required
# Specifies required fields. The script will only send mail, if all
# required fields are filled out. Example:
# <INPUT TYPE="hidden" NAME="required" VALUE="e-mail,subject">
#
# - bgcolor
# Specifies the background color of the confirmation and error pages.
# Default value is white. Example:
# <INPUT TYPE="hidden" NAME="bgcolor" VALUE="black">
#
# - color
# Specifies the font color of the confirmation and error pages.
# Default value is black. Example:
# <INPUT TYPE="hidden" NAME="color" VALUE="white">
#
# - face
# Specifies the font face used for the confirmation and error pages.
# Default value is Arial. Example:
# <INPUT TYPE="hidden" NAME="face" VALUE="Comic Sans MS">
#
# - title
# Specifies the title of the confirmation page. Default value is
# 'message sent'. Example:
# <INPUT TYPE="hidden" NAME="title" VALUE="Thanks for your feedback">
#
# - redirect
# Use it, if you want to use your own confirmation page. Example:
# <INPUT TYPE="hidden" NAME="redirect"
#        VALUE="http://www.server.com/you/thank_you.html">
#
# All other form fields will get mailed to you. You can include as many
# as you like. Example:
# your homepage: <INPUT TYPE="text" NAME="hp" SIZE="40">
# will get mailed as
#   [ hp: ]
# ....   <--- here comes the users input
#
# Don't forget to close the form tag with </FORM>.
#
# c-ya ... bernd

######################################
# Configuration
#
# Uncomment the next four lines, if you don't have access
# to a sendmail program like 'sendmail' or 'qmail-inject'
# and change $smtp_server to your SMTP server and $LOCALHOST
# to the name of your computer.

# use Socket;
# $LOCALHOST   = 'localhost';
# $smtp_server = 'mail.server.com';
# $smtp_port   = 25;


# Uncomment and change the next line to your sendmail program,
# if you have one.  If you don't have one specify a smtp_host above.

# $sendmail = "/usr/sbin/sendmail -t";


# Choose an alias for every recipient and enter it as shown
# (Format:    'alias"   => 'name@server.com').
# The alias has to be in the form field
# <INPUT TYPE="hidden" NAME="to" VALUE="alias">.
%alias = ( 'test'    => 'webmaster@server.com',
           'you'     => 'you@your.server.com',
           'someone' => 'someone@somewhere.com' );

#######################################
# No need to change anything below this line ...
#
%config = ( 'e-mail'   => '',  'subject'  => 'Form Feedback',
            'name'     => '',  'bgcolor'  => 'white',
            'redirect' => '',  'title'    => 'message sent',
            'required' => '',  'face'     => 'Arial',
            'to'       => '',  'color'    => 'black',
            'linkURL'  => '/', 'linkName' => 'home' );

&parse_form;
if( $alias{$in{'to'}} ) { $in{'to'} = $alias{$in{'to'}} }
else { &unknown_user }
&check_required;
&parse_config;
&build_message;
&send_message;
&return_html;
exit;

sub return_html
{
  if( $config{'redirect'} ) { print "Location: $config{'redirect'}\n\n"; exit; }
  print <<"__STOP__";
Content-Type: text/html

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>

<HEAD>
  <TITLE>$config{'title'}</TITLE>
</HEAD>

<BODY BGCOLOR="$config{'bgcolor'}" STYLE="margin:20px">

<H1 ALIGN="center">
  <FONT FACE="$config{'face'}" COLOR="$config{'color'}">
    $config{'title'}
  </FONT>
</H1>

<HR SIZE="1">

<P>
  <FONT FACE="$config{'face'}" COLOR="$config{'color'}">
    The following message has been sent to $config{'to'}:
  </FONT>
</P>

<PRE>$msg</PRE>

<P ALIGN="CENTER">
  <FONT FACE="$config{'face'}" SIZE="+1" COLOR="$config{'color'}">
    <A HREF="$config{'linkURL'}">[ $config{'linkName'} ]</A>
  </FONT>
</P>

</BODY>
</HTML>
__STOP__
}

sub missing_fields
{
  my $err = join( ", ", @_ );
  print <<"__STOP__";
Content-Type: text/html

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>

<HEAD>
  <TITLE>ERROR - missing fields</TITLE>
</HEAD>

<BODY BGCOLOR="$config{'bgcolor'}" STYLE="margin:20px">

<H1 ALIGN="center">
  <FONT FACE="$config{'face'}" COLOR="$config{'color'}">
    ERROR - missing fields
  </FONT>
</H1>

<HR SIZE="1">

<P ALIGN="center">
  <FONT FACE="$config{'face'}" COLOR="$config{'color'}">
    The following required fields were either<BR>
    left blank or not filled out correctly:<BR>
    <B>$err</B><BR>
    Please hit your browsers <B>&lt;back&gt;</B> button<BR>
    and correct them.
  </FONT>
</P>

</BODY>
</HTML>
__STOP__
  exit;
}

sub unknown_user
{
    print <<"__STOP__";
Content-Type: text/html

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>

<HEAD>
  <TITLE>ERROR - unknown user</TITLE>
</HEAD>

<BODY BGCOLOR="$config{'bgcolor'}" STYLE="margin:20px">
<H1 ALIGN="center">
  <FONT FACE="$config{'face'}" COLOR="$config{'color'}">
    ERROR - unknown user<HR SIZE="1">
  </FONT>
</H1>

<HR SIZE="1">

<P ALIGN="center">
  <FONT FACE="$config{'face'}" COLOR="$config{'color'}">
    <B><I>$in{'to'}</I> is not a registered user! </B>
  </FONT>
</P>

<P ALIGN="CENTER">
  <FONT FACE="$config{'face'}" SIZE="+1" COLOR="$config{'color'}">
    <A HREF="$config{'linkURL'}">[ $config{'linkName'} ]</A>
  </FONT>
</P>

</BODY>
</HTML>
__STOP__
  exit;
}

sub build_message
{
  my $now_string = gmtime;
  $msg  = "To: $config{'to'}\n";
  $msg .= "From: $config{'e-mail'} ($config{'name'})\n";
  $msg .= "Subject: $config{'subject'}\n\n";
  foreach ( keys %in )
  {
    $in{$_} =~ s/\r\n/\n/g;
    $msg   .= " [ $_: ]\n";
    $msg   .= "$in{$_}\n\n";
  }
  $msg .= "---\n";
  $msg .= "This message was sent to you by $ENV{'REMOTE_ADDR'}\n";
  $msg .= "on $now_string (GMT).\n";
}

sub send_message
{
  if( defined( $sendmail ) && ( -e $sendmail ) )
  {
    open( MAIL, "| $sendmail" ) or die( "Can't open $sendmail, because: $!\n" );
    print MAIL $msg;
    close( MAIL );
  }
  elsif( $smtp_server && $smtp_port )
  {
    send_smtp_mail( $config{'to'}, $config{'e-mail'}, $msg );
  }
  else { die( "Don't know how to send mail!\nSpecify a smtp_host or a sendmail program!\n" ) }
}

sub check_required
{
  return unless( $in{'required'} );
  my @missing;
  my @required = split( /\,/, $in{'required'} );
  foreach ( @required )
  {
    if( $_ eq 'e-mail' ) { push( @missing, $_ ) unless( &check_mail( $in{$_} ) ) }
    elsif( !$in{$_} )    { push( @missing, $_ ) }
  }
  if( @missing ) { missing_fields( @missing ) }
}

sub check_mail
{
  if( $_[0] =~ /(@.*@)|(\.\.)|(@\.)|(\.@)|(^\.)/ ||
      $_[0] !~ /^.+\@(\[?)[a-zA-Z0-9\-\.]+\.([a-zA-Z]{2,3}|[0-9]{1,3})(\]?)$/ )
  {
    return 0;
  }
  else { return 1 }
}

sub parse_config
{
  foreach ( keys %config )
  {
    if( $in{$_} )
    {
      $config{$_} = $in{$_};
      delete $in{$_};
    }
  }
}

sub parse_form
{
  my( @pairs, $value, $name, $buffer );
  if( $ENV{'REQUEST_METHOD' } eq 'GET' )
  {
    @pairs = split( /&/, $ENV{'QUERY_STRING'} );
  }
  elsif( $ENV{'REQUEST_METHOD'} eq 'POST' )
  {
    read( STDIN, $buffer, $ENV{'CONTENT_LENGTH'} );
    @pairs = split( /&/, $buffer );
  }
  else { die( "unknown REQUEST_METHOD!\n" ) }
  foreach $pair (@pairs)
  {
    ($name, $value) = split( /=/, $pair );
    $name  =~ tr/+/ /;
    $value =~ tr/+/ /;
    $name  =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C", hex($1))/eg;
    $value =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C", hex($1))/eg;
    $name  =~ s/<!--(.|\n)*-->//g;
    $value =~ s/<!--(.|\n)*-->//g;
    if( $in{$name} && $value ) { $in{$name} = "$in{$name}, $value" }
    else { $in{$name} = $value }
  }
}

sub send_smtp_mail
{
  my( $to, $from, $message )   = @_;
  my( $iaddr, $paddr, $proto ) = undef;
  $iaddr = inet_aton( $smtp_server );
  $paddr = sockaddr_in( $smtp_port, $iaddr );
  $proto = getprotobyname( 'tcp' );
  socket( SOCK, PF_INET, SOCK_STREAM, $proto )  or return 0;
  connect( SOCK, $paddr )                       or return 0;
  receive_from_server( \*SOCK )                 or return 0;
  send_to_server( \*SOCK, "HELO $LOCALHOST" )   or return 0;
  receive_from_server( \*SOCK )                 or return 0;
  send_to_server( \*SOCK, "MAIL FROM: <$from>") or return 0;
  receive_from_server( \*SOCK )                 or return 0;
  send_to_server( \*SOCK, "RCPT TO: <$to>" )    or return 0;
  receive_from_server( \*SOCK )                 or return 0;
  send_to_server( \*SOCK, "DATA" )              or return 0;
  receive_from_server( \*SOCK )                 or return 0;
  send_to_server( \*SOCK, "$message\n." )       or return 0;
  receive_from_server( \*SOCK )                 or return 0;
  send_to_server( \*SOCK, "QUIT" )              or return 0;
  receive_from_server( \*SOCK )                 or return 0;
  close( SOCK )                                 or return 0;
  return 1;
}

sub send_to_server
{
  my( $socket )  = shift;
  my( $message ) = shift;
  send( $socket, "$message\n", 0 ) or return 0;
  return 1;
}

sub receive_from_server
{
  my( $socket ) = shift;
  my( $reply );
  while( $reply = <$socket> )
  {
    return 0 if $reply =~ /^5/;
    last      if $reply =~ /^\d+ /;
  }
  return 1;
}