NTLM_AUTH(1) User Commands NTLM_AUTH(1)

NAME

ntlm_auth - tool to allow external access to Winbind's NTLM
authentication function

SYNOPSIS

ntlm_auth

DESCRIPTION

This tool is part of the samba(7) suite.

ntlm_auth is a helper utility that authenticates users using NT/LM
authentication. It returns 0 if the users is authenticated
successfully and 1 if access was denied. ntlm_auth uses winbind to
access the user and authentication data for a domain. This utility is
only intended to be used by other programs (currently Squid and
mod_ntlm_winbind)

OPERATIONAL REQUIREMENTS

The winbindd(8) daemon must be operational for many of these commands
to function.

Some of these commands also require access to the directory
winbindd_privileged in $LOCKDIR. This should be done either by
running this command as root or providing group access to the
winbindd_privileged directory. For security reasons, this directory
should not be world-accessable.

OPTIONS

--helper-protocol=PROTO
Operate as a stdio-based helper. Valid helper protocols are:

squid-2.4-basic
Server-side helper for use with Squid 2.4's basic (plaintext)
authentication.

squid-2.5-basic
Server-side helper for use with Squid 2.5's basic (plaintext)
authentication.

squid-2.5-ntlmssp
Server-side helper for use with Squid 2.5's NTLMSSP
authentication.

Requires access to the directory winbindd_privileged in
$LOCKDIR. The protocol used is described here:
http://devel.squid-cache.org/ntlm/squid_helper_protocol.html.
This protocol has been extended to allow the NTLMSSP
Negotiate packet to be included as an argument to the YR
command. (Thus avoiding loss of information in the protocol
exchange).

ntlmssp-client-1
Client-side helper for use with arbitrary external programs
that may wish to use Samba's NTLMSSP authentication
knowledge.

This helper is a client, and as such may be run by any user.
The protocol used is effectively the reverse of the previous
protocol. A YR command (without any arguments) starts the
authentication exchange.

gss-spnego
Server-side helper that implements GSS-SPNEGO. This uses a
protocol that is almost the same as squid-2.5-ntlmssp, but
has some subtle differences that are undocumented outside the
source at this stage.

Requires access to the directory winbindd_privileged in
$LOCKDIR.

gss-spnego-client
Client-side helper that implements GSS-SPNEGO. This also uses
a protocol similar to the above helpers, but is currently
undocumented.

ntlm-server-1
Server-side helper protocol, intended for use by a RADIUS
server or the 'winbind' plugin for pppd, for the provision of
MSCHAP and MSCHAPv2 authentication.

This protocol consists of lines in the form: Parameter: value
and Parameter:: Base64-encode value. The presence of a single
period . indicates that one side has finished supplying data
to the other. (Which in turn could cause the helper to
authenticate the user).

Currently implemented parameters from the external program to
the helper are:

Username
The username, expected to be in Samba's unix charset.

Examples:
Username: bob

Username:: Ym9i

NT-Domain
The user's domain, expected to be in Samba's unix
charset.

Examples:
NT-Domain: WORKGROUP

NT-Domain:: V09SS0dST1VQ

Full-Username
The fully qualified username, expected to be in Samba's
unix charset and qualified with the winbind separator.

Examples:
Full-Username: WORKGROUP\bob

Full-Username:: V09SS0dST1VQYm9i

LANMAN-Challenge
The 8 byte LANMAN Challenge value, generated randomly by
the server, or (in cases such as MSCHAPv2) generated in
some way by both the server and the client.

Examples:
LANMAN-Challenge: 0102030405060708

LANMAN-Response
The 24 byte LANMAN Response value, calculated from the
user's password and the supplied LANMAN Challenge.
Typically, this is provided over the network by a client
wishing to authenticate.

Examples:
LANMAN-Response:
0102030405060708090A0B0C0D0E0F101112131415161718

NT-Response
The >= 24 byte NT Response calculated from the user's
password and the supplied LANMAN Challenge. Typically,
this is provided over the network by a client wishing to
authenticate.

Examples:
NT-Response:
0102030405060708090A0B0C0D0E0F10111213141516171

Password
The user's password. This would be provided by a network
client, if the helper is being used in a legacy situation
that exposes plaintext passwords in this way.

Examples:
Password: samba2

Password:: c2FtYmEy

Request-User-Session-Key
Upon successful authentication, return the user session
key associated with the login.

Examples:
Request-User-Session-Key: Yes

Request-LanMan-Session-Key
Upon successful authentication, return the LANMAN session
key associated with the login.

Examples:
Request-LanMan-Session-Key: Yes


Warning
Implementers should take care to base64 encode any data (such
as usernames/passwords) that may contain malicious user data,
such as a newline. They may also need to decode strings from
the helper, which likewise may have been base64 encoded.

--username=USERNAME
Specify username of user to authenticate

--domain=DOMAIN
Specify domain of user to authenticate

--workstation=WORKSTATION
Specify the workstation the user authenticated from

--challenge=STRING
NTLM challenge (in HEXADECIMAL)

--lm-response=RESPONSE
LM Response to the challenge (in HEXADECIMAL)

--nt-response=RESPONSE
NT or NTLMv2 Response to the challenge (in HEXADECIMAL)

--password=PASSWORD
User's plaintext password

If not specified on the command line, this is prompted for when
required.

For the NTLMSSP based server roles, this parameter specifies the
expected password, allowing testing without winbindd operational.

--request-lm-key
Retrieve LM session key

--request-nt-key
Request NT key

--diagnostics
Perform Diagnostics on the authentication chain. Uses the
password from --password or prompts for one.

--require-membership-of={SID|Name}
Require that a user be a member of specified group (either name
or SID) for authentication to succeed.

--pam-winbind-conf=FILENAME
Define the path to the pam_winbind.conf file.

--target-hostname=HOSTNAME
Define the target hostname.

--target-service=SERVICE
Define the target service.

--use-cached-creds
Whether to use credentials cached by winbindd.

--allow-mschapv2
Explicitly allow MSCHAPv2.

--offline-logon
Allow offline logons for plain text auth.

-?|--help
Print a summary of command line options.

--usage
Display brief usage message.

-d|--debuglevel=DEBUGLEVEL
level is an integer from 0 to 10. The default value if this
parameter is not specified is 1 for client applications.

The higher this value, the more detail will be logged to the log
files about the activities of the server. At level 0, only
critical errors and serious warnings will be logged. Level 1 is a
reasonable level for day-to-day running - it generates a small
amount of information about operations carried out.

Levels above 1 will generate considerable amounts of log data,
and should only be used when investigating a problem. Levels
above 3 are designed for use only by developers and generate HUGE
amounts of log data, most of which is extremely cryptic.

Note that specifying this parameter here will override the log
level parameter in the ${prefix}/etc/smb.conf file.

--debug-stdout
This will redirect debug output to STDOUT. By default all clients
are logging to STDERR.

--configfile=<configuration file>
The file specified contains the configuration details required by
the client. The information in this file can be general for
client and server or only provide client specific like options
such as client smb encrypt. See ${prefix}/etc/smb.conf for more
information. The default configuration file name is determined at
compile time.

--option=<name>=<value>
Set the smb.conf(5) option "<name>" to value "<value>" from the
command line. This overrides compiled-in defaults and options
read from the configuration file. If a name or a value includes a
space, wrap whole --option=name=value into quotes.

-V|--version
Prints the program version number.

EXAMPLE SETUP

To setup ntlm_auth for use by squid 2.5, with both basic and NTLMSSP
authentication, the following should be placed in the squid.conf
file.

auth_param ntlm program ntlm_auth --helper-protocol=squid-2.5-ntlmssp
auth_param basic program ntlm_auth --helper-protocol=squid-2.5-basic
auth_param basic children 5
auth_param basic realm Squid proxy-caching web server
auth_param basic credentialsttl 2 hours

Note

This example assumes that ntlm_auth has been installed into your
path, and that the group permissions on winbindd_privileged are
as described above.

To setup ntlm_auth for use by squid 2.5 with group limitation in
addition to the above example, the following should be added to the
squid.conf file.

auth_param ntlm program ntlm_auth --helper-protocol=squid-2.5-ntlmssp --require-membership-of='WORKGROUP\Domain Users'
auth_param basic program ntlm_auth --helper-protocol=squid-2.5-basic --require-membership-of='WORKGROUP\Domain Users'

TROUBLESHOOTING

If you're experiencing problems with authenticating Internet Explorer
running under MS Windows 9X or Millennium Edition against ntlm_auth's
NTLMSSP authentication helper (--helper-protocol=squid-2.5-ntlmssp),
then please read the Microsoft Knowledge Base article #239869 and
follow instructions described there.

VERSION

This man page is part of version 4.18.11 of the Samba suite.

AUTHOR

The original Samba software and related utilities were created by
Andrew Tridgell. Samba is now developed by the Samba Team as an Open
Source project similar to the way the Linux kernel is developed.

The ntlm_auth manpage was written by Jelmer Vernooij and Andrew
Bartlett.

Samba 4.18.11 03/13/2024 NTLM_AUTH(1)