On Tue, 2008-05-27 at 14:55 -0400, Christopher J. PeBenito wrote: > On Tue, 2008-05-27 at 14:34 -0400, Stephen Smalley wrote: > > On Tue, 2008-05-27 at 13:55 -0400, Christopher J. PeBenito wrote: > > > On Tue, 2008-05-27 at 13:14 -0400, Stephen Smalley wrote: > > > > On Mon, 2008-05-26 at 19:30 +0900, KaiGai Kohei wrote: > > > > > Hello, > > > > > > > > > > The attached patch enables to obtain the default security context of newly > > > > > created database, defined at /etc/selinux/*/contexts/postgresql_contexts . > > > > > > > > > > The format is as follows: > > > > > -------- > > > > > # > > > > > # Config file for SE-PostgreSQL > > > > > # > > > > > # <domain of client> <type of newly created database> > > > > > unconfined_t sepgsql_db_t > > > > > * sepgsql_db_t > > > > > -------- > > > > > > > > > > '*' means default security context, if given key is not matched for any entry. > > > > > > > > > > This API requires the security context of client as a key, and it returns > > > > > a security context to be attached for a newly created database. > > > > > It has a type field defined in the right-hand of config file, and inherits > > > > > user and lower-range field of given security context as a key. > > > > > > > > > > e.g) > > > > > selabel_lookup(sehandle, &context, "user_u:user_r:user_t:s0", 0); > > > > > returns "user_u:object_r:sepgsql_db_t:s0". > > > > > > > > Chris is investigating the use of roles on objects in order to provide > > > > more fully featured RBAC support without requiring use of per-role > > > > domains. Hardcoding the use of object_r won't be future compatible for > > > > that situation, and more generally we don't want to hardcode policy > > > > information in libselinux at all. > > > > > > > > I'm also unclear as to why type_transition rules aren't a better way of > > > > expressing the above, although I know you've been discussing this with > > > > Chris for some time. Logically I'd expect the client domain to be the > > > > source type of the transition, and the type for the newly created > > > > database to be the new/result type of the transition. What to use as > > > > the target type is less clear; we'd have a similar issue if we were to > > > > use type_transitions for e.g. sockets. It could either be the client > > > > domain both as source and target (self relationship, no related object) > > > > or the client domain as source and the object manager domain as target. > > > > > > > > Chris, what is the objection to using type transitions here, as they are > > > > for labeling new objects and this seems to fit that situation? > > > > > > I think KaiGai took my idea a little to far. My issue was just to have > > > postgres determine what the default label for its objects are via > > > postgresql_contexts. A derived role/type still makes sense to be stated > > > via (type|role)_transition. I suspect there was confusion on this > > > point. I mainly had an issue with statements like: > > > > > > type_transition postgresql_t postgresql_t:db_database sepgsql_db_t; > > > type_transition postgresql_t sepgsql_database_type:db_table sepgsql_sysobj_t; > > > type_transition postgresql_t sepgsql_database_type:db_procedure sepgsql_proc_t; > > > type_transition postgresql_t sepgsql_database_type:db_blob sepgsql_blob_t; > > > type_transition sepgsql_client_type postgresql_t:db_database sepgsql_db_t; > > > > The first four statements don't make sense to me; the last one does make > > sense (i.e. when a postgres client creates a new database, where the > > only related "object" in view is that object manager's context, label > > the new database with sepgsql_db_t). That last instance seems valid as > > a way of expressing types for new databases; the first four statements > > seem to be more suited to this postgres contexts configuration (as they > > are independent of client domain entirely). > > If we have a default contexts configuration, then none of the above > statements would be needed: speaking of the last statement, in the > absence a type_transition, clients that create databases would still get > sepgsql_db_t as the type for the database, since that is the default > database type. > > Nonetheless, it sounds like you don't have a problem with the libselinux > change, as long as its just for the default contexts only, right? Then > creating objects with something other than the default context would be > the job of type_transition. Yes, that sounds right to me. > > > > which I feel should be instead be expressed in a postgresql_contexts > > > file that says the default context for a database is ::seqpgsql_db_t, > > > default context for table is ::sepgsql_sysobj_t, etc. > > > > > > This makes perfect sense staying as a type_transition in the policy: > > > > > > type_transition staff_t sepgsql_sysobj_t:db_tuple staff_sepgsql_sysobj_t; > > > -- Stephen Smalley National Security Agency -- This message was distributed to subscribers of the selinux mailing list. If you no longer wish to subscribe, send mail to majordomo@xxxxxxxxxxxxx with the words "unsubscribe selinux" without quotes as the message.
