Name
ntlm_auth — tool to allow external access to Winbind's NTLM authentication function
Synopsis
ntlm_auth [-d debuglevel] [-l logdir] [-s <smb config file>]
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 indended 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 arbitary external
programs that may wish to use Samba's NTLMSSP
authentication knowlege.
This helper is a client, and as such may be run by any
user. The protocol used is
effectivly 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 for form:
Parameter: value and Paramter::
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).
Curently implemented parameters from the
external program to the helper are:
Warning
Implementors should take care to base64 encode
any data (such as usernames/passwords) that may contain malicous user data, such as
a newline. They may also need to decode strings from
the helper, which likewise may have been base64 encoded.- Username
The username, expected to be in
Samba's unix charset.
Example 2.
Username:: Ym9i
- Username
The user's domain, expected to be in
Samba's unix charset.
Example 3.
Domain: WORKGROUP
Example 4.
Domain:: V09SS0dST1VQ
- Full-Username
The fully qualified username, expected to be in
Samba's and qualified with the
winbind separator.
Example 5.
Full-Username: WORKGROUP\bob
Example 6.
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.
Example 7.
LANMAN-Challege: 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.
Example 8.
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.
Example 9.
NT-Response: 0102030405060708090A0B0C0D0E0F101112131415161718
- 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.
Example 10.
Password: samba2
Example 11.
Password:: c2FtYmEy
- Request-User-Session-Key
Apon sucessful authenticaiton, return
the user session key associated with the login.
Example 12.
Request-User-Session-Key: Yes
- Request-LanMan-Session-Key
Apon sucessful authenticaiton, return
the LANMAN session key associated with the login.
Example 13.
Request-LanMan-Session-Key: Yes
- --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 paramter
specifies the expected password, allowing testing without
winbindd operational.
- --request-lm-key
Retreive 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.
- -V
Prints the program version number.
- -s <configuration file>
The file specified contains the
configuration details required by the server. The
information in this file includes server-specific
information such as what printcap file to use, as well
as descriptions of all the services that the server is
to provide. See smb.conf for more information.
The default configuration file name is determined at
compile time.
- -d|--debuglevel=level
level is an integer
from 0 to 10. The default value if this parameter is
not specified is zero.
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 parameter
in the smb.conf file.
- -l|--logfile=logdirectory
Base directory name for log/debug files. The extension
".progname" will be appended (e.g. log.smbclient,
log.smbd, etc...). The log file is never removed by the client.
- -h|--help
Print a summary of command line options.
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'
VERSION
This man page is correct for version 3.0 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.