#!/usr/bin/perl -wT

# FEX CGI for user registration
#
# Author: Ulli Horlacher <framstag@rus.uni-stuttgart.de>
#

use CGI         qw(:standard);
use CGI::Carp	qw(fatalsToBrowser);
use Fcntl 	qw(:flock :seek :mode);

$CGI::LIST_CONTEXT_WARN = 0;
$CGI::LIST_CONTEXT_WARN = 0;

# import from fex.ph
our (@local_hosts,@local_domains,@local_rhosts,@local_rdomains);
our (@registration_hosts,@registration_domains);
our ($usage_conditions);

# import from fex.pp
our ($mdomain,$logdir,$spooldir,$fra,$hostname,$sendmail,$admin,$bcc);

our $error = "F*EX user registration ERROR";

my $ra = $ENV{REMOTE_ADDR}||0;

my ($CASE,$ESAC);

# add fex lib
(our $FEXLIB) = $ENV{FEXLIB} =~ /(.+)/;
die "$0: no $FEXLIB\n" unless -d $FEXLIB;

# load common code, local config: $HOME/lib/fex.ph
require "$FEXLIB/fex.pp" or die "$0: cannot load $FEXLIB/fex.pp - $!\n";

my $log = "$logdir/fur.log";
my $head = "$ENV{SERVER_NAME} F*EX user registration";

chdir $spooldir or die "$spooldir - $!\n";

my $user = my $id = my $verify = '';

&check_maint;

unless (@local_domains or @local_rdomains) {
  html_error($error,
    "No domains for registrations are defined.",
    "Contact $ENV{SERVER_ADMIN} for details."
  );
}

# look for CGI parameters
foreach my $v (param) {
  my $vv = despace(param($v));
  debuglog("Param: $v=\"$vv\"");
  $CASE =
    $v =~ /^user$/i	? $user		= normalize_address($vv):
    $v =~ /^exuser$/i	? $exuser	= normalize_address($vv):
    $v =~ /^demouser$/i	? $demouser	= normalize_address($vv):
    $v =~ /^verify$/i	? $verify	= lc(checkchars('URL-parameter',$vv)):
    $v =~ /^confirm$/i	? $confirm	= checkchars('URL-parameter',$vv):
    $v =~ /^domain$/i	? $domain	= lc(checkchars('URL-parameter',$vv)):
  $ESAC;
}

if ($confirm) {
  if ($confirm =~ /^(\w+)$/i) {
    $confirm = $1;
  } else {
    http_die("illegal registration key");
  }
  open $confirm,"<.reg/$confirm" or http_die("no registration key $confirm");
  $user = untaint(getline($confirm));
  $id   = getline($confirm);
  close $confirm;
  # unlink ".reg/$confirm";
  unless ($user and $id) {
    http_die("no registration data for key $confirm");
  }
  unless (-f "$user/.auto") {
    http_die("registration expired");
  }
  # if (-f "$user/@") { http_die("$user is already activated") }
  open $user,'>',"$user/@" or http_die("open $user/@ - $!\n");
  print {$user} $id,"\n";  
  close $user or http_die("close $user/@ - $!\n");
  
  http_header("200 OK");
  print html_header($head);
  my $url = "$ENV{PROTO}://$ENV{HTTP_HOST}/fup/" . b64("from=$user&id=$id");
  pq(qq(
    '<h3>Your registration was successful. Your new F*EX account is:</h3>'
    '<p>'
    '<code><a href="$url">$url</a></code>'
    '<p>'
    '(bookmark this URL!)'
    '<p>'
    'or you can use:'
    '<p>'
    '<table>
    '  <tr><td>URL:<td><code><b>$ENV{PROTO}://$ENV{HTTP_HOST}/fup/</code></b></tr>'
    '  <tr><td>Sender:<td><code><b>$user</code></b></tr>'
    '  <tr><td>auth-ID:<td><code><b>$id</code></b></tr>'
    '</table>
    '</body></html>'
  ));
  furlog("confirm: account $user created");
  exit;
}


unless ($user or $exuser or $demouser) {
  http_header("200 OK");
  print html_header($head);
  pq(qq(
    '<form action="$ENV{SCRIPT_NAME}"'
    '      method="post"'
    '      accept-charset="UTF-8"'
    '      enctype="multipart/form-data">'
  ));
  
  if (@local_domains and @local_hosts and ipin($ra,@local_hosts)) {
    $reg = $ra;
    if (grep(/\*/,@local_domains)) {
      pq(qq(
        '  new user (may send to internal or external users):<br>'
        '  <input type="text" name="user" size="80" value="$user">'
        '<p>'
        '  allowed domains are:'
        '<pre>'
      ));
      foreach my $ld (@local_domains) {
        print "  $ld\n";
      }
      print "</pre>\n";
    } else {
      if ($mdomain and not grep /^\Q$mdomain\E$/i,@local_domains) {
        unshift @local_domains,$mdomain;
      }
      my @mydomains = map { "\t<option>$_</option>\n" } @local_domains;
      pq(qq(
        '  new user (may send to internal or external users):<br>'
        '  <input type="text" name="user" size="40" value="$user">\@<select name="domain" size="1">@mydomains</select>'
      ));
    }
  }
  
  if (@local_rdomains and @local_rhosts and 
      (not @registration_hosts or ipin($ra,@registration_hosts))) {
    print "   <p>or<p>\n" if $reg;
    $reg = $ra;
    pq(qq(
      '  new external user (may send only to internal users):<br>'
      '  <input type="text" name="exuser" size="80">'
      '  <p>'
    ));
  }
  
  if (@demo) {
    print "   <p>or<p>\n" if $reg;
    $reg = $ra;
    local $_ = sprintf "with %d MB quota and %d day%s account life time",
      @demo,$demo[1]>1 ? 's' : '';
    pq(qq(
      '  new demo user ($_):<br>'
      '  <input type="text" name="demouser" size="80">'
      '  <p>'
    ));
  }
  
  if ($reg) {
    pq(qq(
      '  <p>'
      '  you must enter your e-mail address and <input type="submit" value="submit">'
      '</form>'
      '<p>'
    ));
    if (@local_rdomains) {
      pq(qq(
        '<p><hr><p>'
        'internal domains are:'
        '<pre>'
      ));
      foreach my $lrd (@local_rdomains) {
        print "  $lrd\n";
      }
    }
    pq(qq(
      '</pre>'
      '<p><hr><p>'
      '<a href="http://fex.rus.uni-stuttgart.de/users.html">User types overview</a>'
      '</body></html>'
    ));
  } else {
    html_error($error,
      "Registrations from your host ($ra) are not allowed.",
      "Contact $ENV{SERVER_ADMIN} for details."
    );
  }
  exit;
}

if ($exuser) {
  unless (@local_rdomains) {
    http_die("no \@local_rdomains");
  }
  if (@registration_hosts and not ipin($ra,@registration_hosts)) {
    html_error($error,
      "Registrations from your host ($ra) are not allowed.",
      "Contact $ENV{SERVER_ADMIN} for details."
    );
  }
  if ($exuser =~ /\@(.+)/) {
    my $exd = $1;
    if (@registration_domains and
        not grep /^\Q$exd\E$/i,@registration_domains) {
      html_error($error,
        "Your domain <code>$exd</code> is not allowed for registration.",
        "Contact $ENV{SERVER_ADMIN} for details."
      );
    }
  } else {
    html_error($error,"<code>$exuser</code> is not an email address");
  }
  $user = $exuser;
} elsif ($demouser) {
  $user = $demouser;
} elsif ($user) {
  unless (@local_domains) {
    html_error($error,
      "No local domains for registration are defined.",
      "Contact $ENV{SERVER_ADMIN} for details."
    );
  }
  my $mydomains = join('|',@local_domains);
  $mydomains =~ s/\./\\./g;
  $mydomains =~ s/\*/.*/g;
  $mydomains .= "|$mdomain" if $mdomain;
  $user .= '@'.$domain if $domain and $user !~ /@/;
  # $user .= '@'.$mdomain if $mdomain and $user !~ /@/;
  
  unless (@local_hosts and ipin($ra,@local_hosts)) {
    html_error($error,
      "Registrations from your host ($ra) are not allowed.",
      "Contact $ENV{SERVER_ADMIN} for details."
    );
  }
  if ("@local_domains" ne "*" and $user !~ /\@($mydomains)$/i) {
    html_error($error,
      "Illegal domain for username.",
      "Contact $ENV{SERVER_ADMIN} for details."
    );
  }
} else {
  html_error($error,"No user type found.");
}

unless (checkforbidden($user)) {
  html_error($error,"<code>$user</code> is not allowed");
}
unless (checkaddress($user)) {
  html_error($error,"<code>$user</code> is not a valid e-mail address");
}
$user = untaint($user);

if (-f "$user/@") {
  html_error(
    $error,
    "you are already registered".
    " (<a href=\"/fup?from=$user&ID_forgotten=1\">I have lost my auth-ID</a>)"
  ); 
}

unless (-d $user) {
  mkdir $user,0770 or http_die("mkdir $user - $!\n");
}

if ($exuser) {
  my $rf;
  # recipients e-mail address restrictions
  $rf = "$exuser/\@ALLOWED_RECIPIENTS";
  open $rf,'>',$rf or http_die("cannot write $rf - $!\n");
  print {$rf} "\@LOCAL_RDOMAINS\n";
  print {$rf} "# See also file \@ALLOWED_RHOSTS\n";
  close $rf;
  # recipients ip restrictions
  $rf = "$exuser/\@ALLOWED_RHOSTS";
  open $rf,'>',$rf or http_die("cannot write $rf - $!\n");
  print {$rf} "\@LOCAL_RHOSTS\n";
  close $rf;
  if (open $user,'>',"$user/.auto") {
    print {$user} "fur:external\n";  
    close $user;
  }
} elsif ($demouser) {
  my $quota = "$demouser/\@QUOTA";
  open $quota,'>',$quota or http_die("cannot write $quota - $!\n");
  printf {$quota} "recipient:%d\n",$demo[0];
  printf {$quota} "sender:%d\n",$demo[0];
  close $quota;
  if (open $user,'>',"$user/.auto") {
    print {$user} "fur:demo\n";  
    close $user;
  }
  open $demouser,'>',"$demouser/.demo" and close $demouser;
} else {
  if (open $user,'>',"$user/.auto") {
    print {$user} "fur:internal\n";  
    close $user;
  }
}

$id = randstring(6);

if ("@local_domains" eq "*") {
  open $id,'>',"$user/@" or http_die("open $user/@ - $!\n");
  print {$id} $id,"\n";  
  close $id or http_die("close $user/@ - $!\n");
  http_header("200 OK");
  print html_header($head);
  $uid = "from=$user&id=$id";
  $b64 = b64($uid);
  pq(qq(
    'Account created:'
    '<pre>'
    '$ENV{PROTO}://$ENV{HTTP_HOST}/fup?$uid'
    '$ENV{PROTO}://$ENV{HTTP_HOST}/fup/$b64'
    '</pre>'
    '</body></html>'
  ));
  exit;
}

# from fexsend
if ($verify eq 'no') {
  open $id,'>',"$user/@" or http_die("open $user/@ - $!\n");
  print {$id} $id,"\n";  
  close $id or http_die("close $user/@ - $!\n");
  http_header("200 OK",'Content-Type: text/plain');
  print "$ENV{PROTO}://$ENV{HTTP_HOST}/fup?from=$user&ID=$id\n";
  furlog("direct: account $user created");
  if ($bcc and open my $mail,"|$sendmail '$bcc' 2>>$log") {
    pq($mail,qq(
      'From: fex'
      'To: $bcc'
      'Subject: F*EX user registration'
      ''
      '$user has been auto-registrated with verify=no'
    ));
    close $mail;
  } else {
    furlog("ERROR: cannot run sendmail - $!\n");
  }
  exit;
}

unless (-d '.reg') {
  mkdir '.reg',0770 or http_die("mkdir .reg - $!\n");
}
$reg = randstring(8);
open $reg,'>',".reg/$reg" or http_die("open .reg/$reg - $!\n");
print {$reg} $user,"\n",$id,"\n";
close $reg or http_die("close .reg/$reg - $!\n");

open my $mail,'|-',$sendmail,$user,$bcc
  or http_die("cannot start sendmail - $!\n");
pq($mail,qq(
  'From: $admin'
  'To: $user'
  'Subject: F*EX user registration request'
  ''
  'To activate your new F*EX account go to this URL:'
  ''
  '$ENV{PROTO}://$ENV{HTTP_HOST}/fur?confirm=$reg'
  ''
));
if ($usage_conditions and open $usage_conditions,$usage_conditions) {
  print {$mail} "The conditions of usage are:\n\n";
  print {$mail} $_ while <$usage_conditions>;
  close $usage_conditions;
}
close $mail or http_die("cannot send mail - $!\n");

http_header("200 OK");
print html_header($head);
print "confirmation e-mail has been sent to <code>$user</code>\n";
print "</body></html>\n"; 
furlog("confirmation request mailed to $user");
exit;


# standard log
sub furlog {
  my $msg = "@_";
  
  $msg =~ s/\n/ /g;
  $msg =~ s/\s+$//;
  
  if (open $log,'>>',$log) {
    flock $log,LOCK_EX;
    seek $log,0,SEEK_END;
    printf {$log} "%s [%s_%s] %s %s\n",
                  isodate(time),$$,$ENV{REQUESTCOUNT},$fra,$msg;
    close $log;
  }
}

sub normalize_address {
  my $a = shift;

  $a = lc(normalize(despace($a)));
  checkchars('address',$a);
  $a =~ s:/:_:g;
  $a =~ s:^\.:_:;
  return untaint($a);
}