With the “allow all” HBAC rule enabled, we have no trouble logging in to any 
machine via ssh. When we disable the “allow all” rule and make specific 
per-machine rules (as per the idea of ‘host based’ in HBAC), we get 
unpredictable results, primarily resulting in an inability to login via ssh. 
This result is intermittent – sometimes we can login, but sometimes we can’t.



HBAC has been created and appears fine on server
[root@vmpr-linuxidm ~]# ipa hbactest --user="pmci\ellul jason" 
--host=emts-facs.unix.petermac.org.au --service=ssh
--------------------
Access granted: True
--------------------
  Matched rules: ad_users
  Matched rules: allow_all
  Matched rules: FACS Computing
  Not matched rules: Computing Cluster


Using the allow_all HBAC all users can log in fine but if we disable it users 
can no longer always login. When the user tries to log in we see the following 
on the host sssd logs:

[sssd[be[unix.petermac.org.au]]] [sdap_parse_entry] (0x1000): OriginalDN: 
[ipaUniqueID=34fb2be6-2137-11e6-9853-005056b00bfd,cn=hbac,dc=unix,dc=petermac,dc=org,dc=au].
[sssd[be[unix.petermac.org.au]]] [sdap_get_generic_op_finished] (0x0400): 
Search result: Success(0), no errmsg set
[sssd[be[unix.petermac.org.au]]] [hbac_attrs_to_rule] (0x1000): Processing rule 
[ad_users]
[sssd[be[unix.petermac.org.au]]] [hbac_user_attrs_to_rule] (0x1000): Processing 
users for rule [ad_users]
[sssd[be[unix.petermac.org.au]]] [hbac_service_attrs_to_rule] (0x1000): 
Processing PAM services for rule [ad_users]
[sssd[be[unix.petermac.org.au]]] [hbac_get_category] (0x0200): Category is set 
to 'all'.
[sssd[be[unix.petermac.org.au]]] [hbac_thost_attrs_to_rule] (0x1000): 
Processing target hosts for rule [ad_users]
[sssd[be[unix.petermac.org.au]]] [hbac_get_category] (0x0200): Category is set 
to 'all'.
[sssd[be[unix.petermac.org.au]]] [hbac_shost_attrs_to_rule] (0x0400): 
Processing source hosts for rule [ad_users]
[sssd[be[unix.petermac.org.au]]] [hbac_attrs_to_rule] (0x1000): Processing rule 
[FACS Computing]
[sssd[be[unix.petermac.org.au]]] [hbac_user_attrs_to_rule] (0x1000): Processing 
users for rule [FACS Computing]
[sssd[be[unix.petermac.org.au]]] [hbac_service_attrs_to_rule] (0x1000): 
Processing PAM services for rule [FACS Computing]
[sssd[be[unix.petermac.org.au]]] [hbac_get_category] (0x0200): Category is set 
to 'all'.
[sssd[be[unix.petermac.org.au]]] [hbac_thost_attrs_to_rule] (0x1000): 
Processing target hosts for rule [FACS Computing]
[sssd[be[unix.petermac.org.au]]] [hbac_shost_attrs_to_rule] (0x0400): 
Processing source hosts for rule [FACS Computing]
[sssd[be[unix.petermac.org.au]]] [hbac_eval_user_element] (0x1000): [41] groups 
for [Ellul ja...@petermac.org.au]
[sssd[be[unix.petermac.org.au]]] [ipa_hbac_evaluate_rules] (0x0080): Access 
denied by HBAC rules
[sssd[be[unix.petermac.org.au]]] [be_pam_handler_callback] (0x0100): Backend 
returned: (0, 6, <NULL>) [Success (Permission denied)]
[sssd[be[unix.petermac.org.au]]] [be_pam_handler_callback] (0x0100): Sending 
result [6][petermac.org.au]
[sssd[be[unix.petermac.org.au]]] [be_pam_handler_callback] (0x0100): Sent 
result [6][petermac.org.au]
[sssd[pam]] [pam_dp_process_reply] (0x0200): received: [6 (Permission 
denied)][petermac.org.au]
[sssd[pam]] [pam_reply] (0x0200): pam_reply called with result [6]: Permission 
denied.
[sssd[pam]] [pam_reply] (0x0200): blen: 32
[sssd[pam]] [client_recv] (0x0200): Client disconnected!
[sssd[nss]] [client_recv] (0x0200): Client disconnected!


Which states Access denied by HBAC rules.

On server we still see
[root@vmpr-linuxidm ~]# ipa hbactest --user="pmci\ellul jason" 
--host=emts-facs.unix.petermac.org.au --service=ssh
--------------------
Access granted: True
--------------------
  Matched rules: ad_users
  Matched rules: FACS Computing
  Not matched rules: Computing Cluster

[root@vmpr-linuxidm ~]# ipa hbacrule-show
Rule name: ad_users           
  Rule name: ad_users
  Host category: all
  Service category: all
  Enabled: TRUE
  User Groups: ad_users

[root@vmpr-linuxidm ~]# ipa hbacrule-show
Rule name: FACS Computing
  Rule name: FACS Computing
  Service category: all
  Description: This server is running Flow Logic. Current server name is 
emts-facs.unix.petermac.org.au
  Enabled: TRUE
  User Groups: facs-compute
  Hosts: emts-facs.unix.petermac.org.au


On the host (emts-facs.unix.petermac.org.au) it shows the user is in the 
correct groups: 10011(facs-compute) and 1718800004(ad_users) which are both 
posix groups local to freeIPA

[root@emts-facs ~]# id "pmci\ellul jason"
uid=1501(jel...@petermac.org.au) gid=1501(jellul) 
groups=1501(jellul),1750642900(secure file transfer 
us...@petermac.org.au),10011(facs-compute),10004(bioinf-core),10005(rcf-staff),1718800004(ad_users)
 (NB: group list truncated for brevity)

Cheers
L.
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