[Freeipa-users] HBAC

[Alexander Bokovoy]

On Tue, 29 Sep 2015, TomK wrote:
>Hey Guy's,
>
>(Sending this again as I didn't have this email included in the 
>freeipa-users mailing list so not sure if the other message will get 
>posted.)
>
>Before I post a ticket to RH Support for an RFE, I'll post the request 
>here to get some feedback on options and what ideas folks have.  I've 
>a situation as follows.  I have the following setup in WS 2012 AD DC:
>
>TomK (user)
>TomK Groups:
>                unixg
>                windowsg
>
>unixg has the 'host' attribute defined 'lab01,lab02,lab03,lab04'
>windowsg has the 'host' attribute defined 'lab06,lab07,lab08,lab09'
>
>TomK(user) also has the 'host' attribute defined as per the proper RFC 
>for LDAP.  With SSSD rules I can define the rules to read the user 
>'host' attribute but not the group 'host' attribute:
>
>
>|access_provider = ldap ldap_access_order = host 
>ldap_user_authorized_host = host|
>
>
>Essentially TomK to be given access to hosts listed in the 'host' 
>attribute but denied entry into lab05 for example (not listed in any 
>group 'host' attribute above) to the server.   If I have a new user 
>that has joined that particular team at our organization, I can simply 
>add her/him to the above groups and this user would get access only to 
>the listed servers in 'host' attribute by default. I don't need to 
>specify new groups in customized sssd.conf or ldap.conf files or in 
>sshd config files.  Hence less to update with Salt or any other CM 
>suite.  I've managed to setup SUDO rules and with the 
>openssh-ldap.diff schema SSH public keys could be stored in AD as well 
>and be read by OpenSSH.  So aside from the HBAC capability on groups, 
>virtually all our needs are handled by the WS2012 AD DC as it has to 
>follow the OpenLDAP standard anyway.  Now to get this we considered 
>and are still considering FreeIPA.  However this idea poses a set of 
>challenges:
>
>1) In large organizations where the AD support department are only 
>trained in Windows AD setup and configuration (Only windows guy's) 
>this would require a minimal of 3 bodies to support that know 
>LDAP/Linux.  This is a large cost.
>
>2) The additional server requires the same hardening as the Windows AD 
>DC servers meaning a new procedure has to be carved out for the 2+ 
>FreeIPA servers to be supported, hardened and maintained (upgraded).
>
>Now I probably sound somewhat anti-FreeIPA, however the challenges of 
>implementing it in large organizations surface after some 
>deliberation, so probably better to list then as it may help direct 
>development of the product to contend with the challenges (Like having 
>a document fully dedicated to hardening a FreeIPA server with selinux 
>and other technologies in easy to maintain configuration).   I could 
>be mistaken but some folks mention that it's 'better' to implement 
>this sort of HBAC through other means (?? iptables ??) but never tried 
>the alternatives yet.
>
>So, cutting to the end, would it be possible to add an attribute like:
>
>|ldap_user_authorized_host|
>
>but perhaps called 'ldap_group_authorized_host' to the SSSD code to 
>enable reading the 'host' attribute on AD/LDAP defined groups?
In FreeIPA we support HBAC rules for AD users and groups. What exactly
is wrong with that?

See 'ipa help trust' for details how to map AD groups to IPA groups and
then 'ipa help hbacrule' for how to limit access of those groups to
specific hosts and services on them.

This is all covered well in the guide:
https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/Linux_Domain_Identity_Authentication_and_Policy_Guide/index.html

-- 
/ Alexander Bokovoy