#!/usr/bin/perl
print "Content-type: text/plain\n\n";
if ($ENV{'REMOTE_ADDR'} ne "216.127.32.37") {
   print "Wrong IP: ".$ENV{'REMOTE_ADDR'}."\n";
   exit;
}
if ($ENV{'REQUEST_METHOD'} ne "POST") {
   print "Yup, Good Test.\n";
   exit(1);
}
while(<STDIN>) {
    $data .= $_;
}
if ( ($data =~ /^CHECK/) || ($data =~ /^DELETE/) ) {
    ($command, $ht_file, $user) = split(',',$data);
}
elsif ( $data =~ /^ADD/ ) {
    ($command, $ht_file, $user, $password) = split(',',$data);
}
elsif ( $data =~ /^BATCH/ ) {
    ($command, $ht_file, $users_pwds) = split('\+',$data);
    @user_pwd_array = split(',',$users_pwds);
}
else {
    print "COMMAND NOT RECOGNIZED\n";
    exit(-1);
}
if ( $command =~ /CHECK/ || $command =~ /DELETE/ ) {
    if ( -e $ht_file ) {
    }
    else {
        print "\nERROR: password file not found: $ht_file\n";
        exit(-1);
    }
}
$rtn = system("cp $ht_file $ht_file.bak");
if ( $rtn != 0 ) {
    print $! . " ERROR: Can't make backup of $ht_file - CHECK READ PERMISSIONS OF $ht_file AND WRITE PERMISSIONS OF THE DIRECTORY!!!";
}
if ( $debug == 1 ) { print "Made backup ht_file RTN:$rtn"; }
open(AC_FILE, "$ht_file") || die "ERROR - can't open $ht_file</body></html>"; # open for read
&read_lock('AC_FILE');
while (<AC_FILE>) {
    chop($_);
    ($tmp_usr,$tmp_pwd) = split(/:/,$_);
    if ( $tmp_usr eq "" ) { next; }
    $users{$tmp_usr} = $tmp_pwd;
}
&clr_lock('AC_FILE');
close(AC_FILE);
if ($users{$user}) {
    $found = 1;
}
else {
    $found = 0;
}

if ( $debug ) { print "user_there_variable=$found\n"; }

if ( $command =~ /CHECK/ ) {
    if ( $found ) { print "FOUND\n"; }
    else          { print "NOT_FOUND\n"; }

    exit(0);
}
elsif ( $command =~ /ADD/ ) {
    srand;
    $salt = &to64(int(rand(2147483648)), 2);
    $crypt_pwd = crypt($password, $salt);
    $users{$user} = $crypt_pwd;
    if ( $found ) {
        if ( write_new() ) {
            print "ADDED\n";
        }
        else {
            print "ERROR\n";
        }
    }
    else {
        if ( !open(AC_FILE, ">>$ht_file") ) {
            print "ERROR: can't open for writing/append ($ht_file) - check permissions";
            exit(-1);
        }
        &write_lock('AC_FILE');
        print AC_FILE "$user:$crypt_pwd\n";
        flush('AC_FILE');
        &clr_lock('AC_FILE');
        close(AC_FILE);
        print "ADDED\n";
    }

    exit(0);
}
elsif ( $command =~ /DELETE/ ) {
    if ( $found ) {
        delete $users{"$user"};
        write_new();
    }
    print "DELETED $user\n";
    exit(0);
}
elsif ( $command =~ /BATCH/ ) {

    print "ADDING User/Pwds\n";
    my $count = 0;
    foreach $user_pwd (@user_pwd_array) {
        ++$count;
        ($user,$pwd) = split(':',$user_pwd);

        srand;
        $salt = &to64(int(rand(2147483648)), 2);
        $crypt_pwd = crypt($pwd, $salt);

        $users{$user} = $crypt_pwd;
    }
    print "WRITING $count Encrypted  User/Pwds to file\n";
    write_new();
    print "DONE WITH BATCH ADD\n";
    exit(0);
}
else {
    print "COMMAND NOT RECOGNIZED\n";
    exit(-1);
}

exit(0);

sub write_new() {
        $file_string = "";

        while (($user_temp,$pwd)=each(%users)) {
            $file_string .= "$user_temp:$pwd\n";
        }


        if ( !open(AC_FILE, ">$ht_file") ) {
            print "ERROR: can't open for writing/new ($ht_file) - check write permissions on this directory";
            return(0);
        }
        &write_lock('AC_FILE');
        print AC_FILE $file_string;
        flush('AC_FILE');
        &clr_lock('AC_FILE');
        close(AC_FILE);

        chmod 0666, $ht_file;

        return(1);
}

sub flush {
    local($old) = select(shift);
    $| = 1;
    print "";
    $| = 0;
    select($old);
}

sub LOCK_SH {1;}
sub LOCK_EX {2;}
sub LOCK_NB {4;}
sub LOCK_UN {8;}

sub read_lock {
    local($rc,$fh);
    $fh = shift;
    $rc = flock($fh, &LOCK_SH());
    return $rc;
}

sub write_lock {
    local($rc,$fh);
    $fh = shift;
    $rc = flock($fh, &LOCK_EX());
    return $rc;
}

sub clr_lock {
    local($rc,$fh);
    $fh = shift;
    $rc = flock($fh, &LOCK_UN());
    return $rc;
}


sub seedchar {
    ('a'..'z','A'..'Z','0'..'9','.','/')[rand(64)];
}

sub to64 {
   $itoa64 = "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
   local($v, $n) = @_;
   local($s);
   while (--$n >= 0) {
      $s .= substr($itoa64, ($v % 64), 1);
      $v >>= 6;
   }
   return $s;
}