AuthenNTLM(3pm)
NAME
Apache2::AuthenNTLM - Perform Microsoft NTLM and Basic User
Authentication
SYNOPSIS
<Location /> PerlAuthenHandler Apache2::AuthenNTLM AuthType ntlm,basic AuthName test require valid-user # domain pdc bdc PerlAddVar ntdomain "name_domain1 name_of_pdc1" PerlAddVar ntdomain "other_domain pdc_for_domain bdc_for_domain" PerlSetVar defaultdomain wingr1 PerlSetVar splitdomainprefix 1 PerlSetVar ntlmdebug 1 </Location>
DESCRIPTION
The purpose of this module is to perform a user authentication via
Microsoft's NTLM protocol. This protocol is supported by all versions
of the Internet Explorer and is mainly useful for intranets. Depending
on your preferences setting IE will supply your windows logon
credentials to the web server when the server asks for NTLM
authentication. This saves the user to type in his/her password again.
The NTLM protocol performs a challenge/response to exchange a random
number (nonce) and get back a md4 hash, which is built from the user's
password and the nonce. This makes sure that no password goes over the
wire in plain text.
The main advantage of the Perl implementation is, that it can be easily
extended to verify the user/password against other sources than a
windows domain controller. The defaultf implementation is to go to the
domain controller for the given domain and verify the user. If you want
to verify the user against another source, you can inherit from
Apache2::AuthenNTLM and override it's methods.
To support users that aren't using Internet Explorer,
Apache2::AuthenNTLM can also perform basic authentication depending on
its configuration.
IMPORTANT: NTLM authentification works only when KeepAlive is on. (If
you have set ntlmdebug 2, and see that there is no return message (type
3), check your httpd.conf file for "KeepAlive Off". If KeepAlive Off,
then change it to KeepAlive On, restart Apache, and test again).
CONFIGURATION
AuthType
Set the type of authentication. Can be either "basic", "ntlm" or
"ntlm,basic" for doing both.
AuthName
Set the realm for basic authentication
require valid-user
- Necessary to tell Apache to require user authentication at all. Can
also used to allow only some users, e.g. - require user foo bar
- Note that Apache2::AuthenNTLM does not perform any authorization, if
the require xxx is executed by Apache itself. Alternatively you can use another (Perl-)module to perform authorization. - PerlAddVar ntdomain "domain pdc bdc"
- This is used to create a mapping between a domain and both a pdc and
bdc for that domain. Domain, pdc and bdc must be separated by a space. You can specify mappings for more than one domain. - NOTE FOR WINDOWS ACTIVE DIRECTORY USERS: You must specify the DOMAIN
for the pdc and/or bdc. Windows smb servers will not accept ip address in dotted quad form. For example, the SPEEVES domain pdc has an ip
address of 192.168.0.2. If you enter the ntdomain as: - PerlAddVar ntdomain 192.168.0.2
- Then you will never be able be able to authenticate to the remote
server correctly, and you will receive a "Can not get NONCE" error in
the error_log. You must specify it as: - PerlAddVar ntdomain SPEEVES
- This means that you will need to resolve the DOMAIN locally on the web server machine. I put it into the /etc/hosts file.
- For the complete run-down on this issue, check out:
- http://www.gossamer-threads.com/archive/mod_perl_C1/modperl_F7/%5BFwd:_Re:_Apache::AuthenNTLM-2.04_Problems..%5D_P104237/
- PerlSetVar defaultdomain
- Set the default domain. This is used when the client does not provide
any information about the domain. - PerlSetVar fallbackdomain
- fallbackdomain is used in cases where the domain that the user supplied
isn't configured. This is useful in environments where you have a lot
of domains, which trust each other, allowing you to always authenticate against a single domain, (removing the need to configure all domains
available in your network). - PerlSetVar ntlmauthoritative
- Setting the ntlmauthoritative directive explicitly to 'off' allows
authentication to be passed on to lower level modules if AuthenNTLM
cannot authenticate the user and the NTLM authentication scheme is
used. If set to 'on', which is the default, AuthenNTLM will try to
verify the user and, if it fails, will give an Authorization Required
reply. - PerlSetVar basicauthoritative
- Setting the ntlmauthoritative directive explicitly to 'off' allows
authentication to be passed on to lower level modules if AuthenNTLM
cannot authenticate the user and the Basic authentication scheme is
used. If set to 'on', which is the default, AuthenNTLM will try to
verify the user and if it fails will give an Authorization Required
reply. - PerlSetVar ntlmsemkey
- There are troubles when two authentication requests take place at the
same time. If the second request starts, before the first request has
successfully verified the user to the smb (windows) server, the smb
server will terminate the first request. To avoid this
Apache2::AuthenNTLM serializes all requests. It uses a semaphore for
this purpose. The semkey directive set the key which is used (default: 23754). Set it to zero to turn serialization off. - PerlSetVar ntlmsemtimeout
- This set the timeout value used to wait for the semaphore. The default
is two seconds. It is very small because during the time Apache waits
for the semaphore, no other authentication request can be sent to the
windows server. Also Apache2::AuthenNTLM only asks the windows server
once per keep-alive connection, this timeout value should be as small
as possible. - PerlSetVar splitdomainprefix
- If set to 1, $self -> map_user ($r) will return "username" else $self
-> map_user ($r) will return "domain\username" - Default is "domain\username"
- PerlSetVar ntlmdebug
- Set this to 1 if you want extra debugging information in the error log. Set it to 2 to also see the binary data of the NTLM headers.
OVERRIDEABLE METHODS
- Each of the following methods takes the Apache object as argument.
Information about the current authentication can be found inside the
object Apache2::AuthenNTLM itself. To override the methods, create our own class which inherits from Apache2::AuthenNTLM and use it in
httpd.conf e.g. - PerlAuthenHandler Apache2::MyAuthenNTLM
- $self -> get_config ($r)
- Will be called after the object is setup to read in configuration
informations. The $r -> dir_config can be used for that purpose. - $self -> get_nonce ($r)
- Will be called to setup the connection to the windows domain controller
for $self -> {domain} and retrieve the nonce. In case you do not
authenticate against a windows machine, you simply need to set $self -> {nonce} to a 8 byte random string. Returns undef on error. - $self -> verify_user ($r)
- Should verify that the given user supplied the right credentials.
Input: - $self -> {basic}
- Set when we are doing basic authentication
- $self -> {ntlm}
- Set when we are doing ntlm authentication
- $self -> {username}
- The username
- $self -> {password}
- The password when doing basic authentication
- $self -> {usernthash}
- The md4 hash when doing ntlm authentication
- $self -> {userdomain}
- The domain
- returns true if this is a valid user.
- $self -> map_user ($r)
- Is called before to get the user name which should be available as
REMOTE_USER to the request. Default is to return DOMAIN\USERNAME. - Example for overriding
- The following code shows the a basic example for creating a module
which overrides the map_user method and calls AuthenNTLM's handler only if a precondition is met. Note: The functions preconditon_met and
lookup_user do the real work and are not shown here.
package Apache2::MyAuthenNTLM ;- use Apache2::AuthenNTLM ;
- @ISA = ('Apache2::AuthenNTLM') ;
- sub handler ($$)
{
my ($self, $r) = @_ ;return Apache2::AuthenNTLM::handler ($self, $r) if (precondition_met()) ;
return DECLINED ;
} - sub map_user
{
my ($self, $r) = @_ ;return lookup_user ($self->{userdomain}, $self->{username}) ;
}
SUPPORT
Speeves: Thanks to everyone that is helping to find bugs, etc. in this
module. Please, feel free to contact me and let me know of any strange
things are going on with this module. Also, please copy the
modperl@perl.apache.org mailing list, as there are probably many others
that are experiencing the same problems as you, and they may be able to
return an answer faster than I can by myself. Thanks :)
SEE ALSO
An implementation of this module which uses cookies to cache the
session.
Apache-AuthCookieNTLM - Leo Lapworth
http://search.cpan.org/~llap/Apache-AuthCookieNTLM/
AUTHOR
G. Richter (richter@dev.ecos.de) Ported by Shannon Eric Peevey
(speeves@unt.edu)
- Development of this package, versions 0.01-0.13 was sponsored by:
Siemens: http://www.siemens.com