NAME

Apache::LoggedAuthDBI

SYNOPSIS

# Configuration in httpd.conf or startup.pl:

PerlModule Apache::LoggedAuthDBI

# Authentication and Authorization in .htaccess:

AuthName DBI
AuthType Basic

PerlAuthenHandler Apache::AuthDBI::authen
PerlAuthzHandler  Apache::AuthDBI::authz

PerlSetVar Auth_DBI_data_source   dbi:driver:dsn
PerlSetVar Auth_DBI_username      db_username
PerlSetVar Auth_DBI_password      db_password
#DBI->connect($data_source, $username, $password)

PerlSetVar Log_ADBI_table         login_log
PerlSetVar Log_ADBI_ip_field      IPaddress
PerlSetVar Log_ADBI_un_field      username
PerlSetVar Log_ADBI_status_field  status
PerlSetVar Log_ADBI_time_field    timestamped
# data required to access the log table

PerlSetVar Auth_DBI_pwd_table     users
PerlSetVar Auth_DBI_uid_field     username
PerlSetVar Auth_DBI_pwd_field     password
# authentication: SELECT pwd_field FROM pwd_table WHERE uid_field=$user

require valid-user

DESCRIPTION

This is an extension of Apache::AuthDBI by Edmund Mergl. Its purpose is
to add a degree of protection against brute force attacks and password sharing.
To accomplish this LoggedAuthDBI makes use of a log table that records IP, username,
status and time of any given login attempt handled by this module.
Whenever it is called it will perform four checks:

• Did IPaddress 123 make X failed attempts in Y seconds?

  (autoreject IP addresses that have too many failed attempts on record)

• Did IPaddress 123 make X attempts in Y seconds?

  (if X gets very large while Y is small, the possibility of a brute force
  attack taking place is very real indeed)

• Has username foo been rejected X times in Y seconds?

  (this check as a means to help against proxy rotation in combination with
  brute force attempts)

• Does username foo have logins from X different IPaddresses in Y seconds?

  (this would surely indicate password sharing)

Should none of the four checks yield a violation AuthDBI is called and its
return value used without modification.
Otherwise it will redirect to a different filename while returning OK. This
will cause a bruteforce tool to think it was successful in its attempt to
guess a valid login/pass combination and either stop or collect this combination
into its list of valid options.

Consider this module beta ware as it has only seen action in the original
context it was created for and at.

LOG TABLE

While it is possible that a log table is already in place it might need some
adjustment. See this MySQL CREATE TABLE command to see the required structure/
how to create. Table name and field names are, of course, arbitrary as they are
determined in the .htaccess file.

<mysql>
CREATE TABLE `member_log` (
 `id` int(10) unsigned NOT NULL auto_increment,
 `username` varchar(64) default NULL,
 `IPaddress` varchar(15) default NULL,
 `status` varchar(15) default NULL,
 `timestamped` timestamp(14) NOT NULL,
 PRIMARY KEY  (`id`)
) TYPE=MyISAM
</mysql>

LIST OF TOKENS

Only the tokens specific to this module are discussed here. For reference
on the remaining tokens consult the documentation on Apache::AuthDBI.

• Log_ADBI_table

  Name of the table where login records will be kept.
  Has to at least contain fields holding IPaddress, username, status and timestamp.

• Log_ADBI_ip_field

  Field name of the Log_ADBI_table containing the IPaddress of the login attempt.

• Log_ADBI_un_field

  Field name of the Log_ADBI_table containing the username of the login attempt.

• Log_ADBI_status_field

  Field name of the Log_ADBI_table containing the status of the login attempt that was made.

• Log_ADBI_time_field

  Field name of the Log_ADBI_table containing the timestamp of the login attempt. 

CONFIGURATION

The module should be loaded upon startup of the Apache daemon.
Add the following line to your httpd.conf:

PerlModule Apache::LoggedAuthDBI

Also, copy the following HTML files to the document root of Apache. These are needed
as this module will redirect to these resources in case of detected perpetration. Using
your own is perfectly okay as long as you either keep the naming or edit the filenames
in the module.

• blocked.html

• brute_force.html

• pass_sharing.html

PREREQUISITES

Apache::AuthDBI is required. This implies that minimum requirements for that
module must be met.

AUTHORS

• Apache::LoggedAuthDBI by Sung-Hun Kim

• Apache::AuthDBI by Edmund Mergl; now maintained and supported by the modperl mailinglist, subscribe by sending mail to modperl-subscribe@perl.apache.org.

SEE ALSO

AuthDBI

COPYRIGHT

Copyright (c) 2005 Sung-Hun Kim. All rights reserved. 
This program is free software;  you can redistribute it 
and/or modify it under the same terms as Perl itself.