Red Hat Bugzilla – Bug 1178116
Default selinux policy prevents ssh-ldap-helper from connecting to LDAP server
Last modified: 2016-02-09 03:29:10 EST
Description of problem: When using openssh-ldap the default selinux policy prevents connections to the LDAP server. Version-Release number of selected component (if applicable): openssh-6.4p1-8.el7.x86_64 openssh-ldap-6.4p1-8.el7.x86_64 How reproducible: Install and configure openssh-ldap, attempt to SSH to the host. Steps to Reproduce: 1. 2. 3. Actual results: Error in the audit log: type=AVC msg=audit(1420058593.479:6643): avc: denied { name_connect } for pid=26849 comm="ssh-ldap-helper" dest=389 scontext=system_u:system_r:sshd_t:s0-s0:c0.c1023 tcontext=system_u:object_r:ldap_port_t:s0 tclass=tcp_socket and LDAP not queried for the public key. Expected results: LDAP queried for the public key and result returned Additional info: From the setroubleshoot script: If you believe that ssh-ldap-helper should be allowed name_connect access on the tcp_socket by default. Then you should report this as a bug. You can generate a local policy module to allow this access. Do allow this access for now by executing: # grep ssh-ldap-helper /var/log/audit/audit.log | audit2allow -M mypol # semodule -i mypol.pp
It looks like this can also be resolved with: setsebool -P authlogin_nsswitch_use_ldap 1 This is not mentioned in the HOWTO.ldap-keys file, it should be added there.
# rpm -qa selinux-policy\* selinux-policy-mls-3.12.1-153.el7_0.13.noarch selinux-policy-minimum-3.12.1-153.el7_0.13.noarch selinux-policy-3.12.1-153.el7_0.13.noarch selinux-policy-doc-3.12.1-153.el7_0.13.noarch selinux-policy-sandbox-3.12.1-153.el7_0.13.noarch selinux-policy-devel-3.12.1-153.el7_0.13.noarch selinux-policy-targeted-3.12.1-153.el7_0.13.noarch # sesearch -s sshd_t -t ldap_port_t -c tcp_socket -p name_connect -A -C Found 3 semantic av rules: DT allow nsswitch_domain ldap_port_t : tcp_socket { recv_msg send_msg name_connect } ; [ authlogin_nsswitch_use_ldap ] ET allow sshd_t reserved_port_type : tcp_socket name_connect ; [ nis_enabled ] ET allow nsswitch_domain reserved_port_type : tcp_socket name_connect ; [ nis_enabled ] # Usage of authlogin_nsswitch_use_ldap boolean is the right way to go.
$ audit2allow type=AVC msg=audit(1420058593.479:6643): avc: denied { name_connect } for pid=26849 comm="ssh-ldap-helper" dest=389 scontext=system_u:system_r:sshd_t:s0-s0:c0.c1023 tcontext=system_u:object_r:ldap_port_t:s0 tclass=tcp_socket #============= sshd_t ============== #!!!! This avc can be allowed using one of the these booleans: # nis_enabled, authlogin_nsswitch_use_ldap allow sshd_t ldap_port_t:tcp_socket name_connect; As it's suggested in comment 3, setting authlogin_nsswitch_use_ldap variable to yes should fix the issue, eg: # setsebool -P authlogin_nsswitch_use_ldap on or # semanage boolean --modify --on authlogin_nsswitch_use_ldap
Closed without adding anything to the README? If I had this issue, it seems that someone else will as well.
I missed that, sorry. We'll provide a note in HOWTO.ldap-keys
I would be for such addition to HOWTO.ldap-keys: =============== @@ -51,6 +51,9 @@ * There are some debug options * Example /usr/libexec/openssh -s -f /etc/ldap.conf -w -d >> /tmp/ldapdebuglog.txt +7) Configure SELinux boolean which allows ldap-helper to bind ldap server + Run this command + # setsebool -P authlogin_nsswitch_use_ldap on HOW TO MIGRATE FROM LPK ===============
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://rhn.redhat.com/errata/RHSA-2015-2088.html