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Puppet, Apache, mod_passenger, and SELinux

At work, we are currently working on deploying Puppet with Apache on RedHat Enterprise Linux 6 to replace our cfengine on RHEL4/5 setup.

We install Puppet direct from Puppetlabs, and mod_passenger from Stealthy Monkeys.

There are quite a few issues with directory permissions and SELinux. The directory permission issues are fairly easy to diagnose because the httpd log files, and the error messages that httpd sends back generally tell you what permissions it expected.

SELinux is a different kettle of fish. After doing ausearch and using audit2allow, plus a little bit of pruning, this seems to be a minimal set of permissions that allow puppet to run under Passenger and Apache (the following is a .te file):

module puppet_passenger 1.5;

require {
        type httpd_t;
        type httpd_passenger_helper_t;
        type port_t;
        type puppet_var_lib_t;
        type proc_net_t;
        class dir { write getattr read create search add_name };
        class file { write append relabelfrom getattr read relabelto create open };
        class udp_socket name_bind;

#============= httpd_passenger_helper_t ==============
allow httpd_passenger_helper_t httpd_t:dir { getattr search };
allow httpd_passenger_helper_t httpd_t:file { read open };

#============= httpd_t ==============
#!!!! This avc can be allowed using the boolean 'allow_ypbind'

allow httpd_t port_t:udp_socket name_bind;

allow httpd_t proc_net_t:file { read getattr open };

allow httpd_t puppet_var_lib_t:dir { write read create add_name };
allow httpd_t puppet_var_lib_t:file { relabelfrom relabelto create write append };
To install these changes:
# mkdir -p /usr/share/selinux/packages/puppet_passenger/
# cp puppet_passenger.te /usr/share/selinux/packages/puppet_passenger
# cd /usr/share/selinux/packages/puppet_passenger
# checkmodule -M -m -o puppet_passenger.mod puppet_passenger.te
# semodule_package -o puppet_passenger.pp -m puppet_passenger.mod
# semodule -i puppet_passenger.pp

And if you ever want to remove the permissions, just do:
# semodule -r puppet_passenger.pp