rlm_mschap(5)

NAME
rlm_mschap - FreeRADIUS Module

DESCRIPTION
The rlm_mschap module provides MS-CHAP and MS-CHAPv2 authentication support.

This module validates a user with MS-CHAP or MS-CHAPv2 authentication. It should be listed in both the authorize and authenticate sections. In authorize, it will look for MS-CHAP Challenge/Response attributes in the Acess-Request, and configure itself to be the module called for the authenticate section.

The module can authenticate the MS-CHAP session via plain-text passwords (User-Password attribute), or NT passwords (NT-Password attribute). The module can perform authentication against an NT domain by using the ntlm_auth program.

SMB Integration
The module also enforces the SMB-Account-Ctrl attribute. See the Samba documentation for the meaning of SMB account control. The module does not read Samba password files. Instead, the rlm_passwd module should be used to read a Samba password file, and to supply an NT-Password attribute which this module can use. See the etc_smbpasswd module in radiusd.conf for more details.

MODULE CONFIGURATION
The main configuration items to be aware of are:

use_mppe
    Unless this is set to 'no', FreeRADIUS will add MS-CHAP-MPPE-Keys for MS-CHAPv1 and MS-MPPE-Recv-Key/MS-MPPE-Send-Key for MS-CHAPv2. The default is 'yes'.

require_encryption
    If MPPE is enabled, setting this attribute to 'yes' will cause the MS-MPPE-Encryption-Policy attribute to be set to require encryption. The default is 'no'.

require_strong
    If MPPE is enabled, setting this attribute to 'yes' will cause the MS-MPPE-Encryption-Types attribute to be set to require a 128 bit key. The default is 'no'.

with_ntdomain_hack
    Windows clients send User-Name in the form of "DOMAIN\User", but send the challenge/response based only on the User portion. Setting this value to yes, enables a work-around for this error. The default is 'no'.

ntlm_auth
    Use the ntlm_auth program for authentication against Samba, or a Windows NT or Active Directory Domain Controller. For machine authentication, the following configuration should be used: ntlm_auth = "/path/to/ntlm_auth --username=%{mschap:User-Name:-None} --challenge=%{mschap:Challenge:-00} --nt-response=%{mschap:NT-Response:-00} --domain=%{mschap:NT-Domain:-YOUR_DEFAULT_DOMAIN} If configured, ntlm_auth will always be called, even if there is a clear-text or NT-Password available for the user. You can force ntlm_auth to not be used by setting MS-CHAP-Use-NTLM-Auth := No in the users file, or in a database such as SQL.

SECTIONS
authorization, authentication

FILES
/etc/raddb/radiusd.conf

SEE ALSO
radiusd(8), radiusd.conf(5)

AUTHOR
Chris Parker, cparker@segv.org