Replace * or any permission set containing create with
create_socket_perms or create_stream_socket_perms.
Add net_domain() to all domains using network sockets and
delete rules already covered by domain.te or net.te.
For netlink_route_socket, only nlmsg_write needs to be separately
granted to specific domains that are permitted to modify the routing
table. Clarification: read/write permissions are just ability to
perform read/recv() or write/send() on the socket, whereas nlmsg_read/
nlmsg_write permissions control ability to observe or modify the
underlying kernel state accessed via the socket.
See security/selinux/nlmsgtab.c in the kernel for the mapping of
netlink message types to nlmsg_read or nlmsg_write.
Delete legacy rule for b/12061011.
This change does not touch any rules where only read/write were allowed
to a socket created by another domain (inherited across exec or
received across socket or binder IPC). We may wish to rewrite some or all
of those rules with the rw_socket_perms macro but that is a separate
change.
Change-Id: Ib0637ab86f6d388043eff928e5d96beb02e5450e
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
There is some overlap between socket rules in app.te and the net.te rules,
but they aren't quite identical since not all app domains presently include
the net_domain() macro and because the rules in app.te allow more permissions
for netlink_route_socket and allow rawip_socket permissions for ping.
The current app.te rules prevent one from ever creating a non-networked app
domain. Resolve this overlap by:
1) Adding the missing permissions allowed by app.te to net.te for
netlink_route_socket and rawip_socket.
2) Adding net_domain() calls to all existing app domains that do not already
have it.
3) Deleting the redundant socket rules from app.te.
Then we'll have no effective change in what is allowed for apps but
allow one to define app domains in the future that are not allowed
network access.
Also cleanup net.te to use the create_socket_perms macro rather than *
and add macros for stream socket permissions.
Change-Id: I6e80d65b0ccbd48bd2b7272c083a4473e2b588a9
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Change I4be1c987a5d69ac784a56d42fc2c9063c402de11 removed all
netdomain allow rules at the same time domains were made unconfined.
Prior to that change, any domain that used the net_domain() macro
would be granted permissions required to use the network via these rules.
The change made the netdomain attribute unused in any rules, thereby
rendering the net_domain() calls pointless and requiring the allow
rules to be duplicated for any domain requiring network access. There
are two ways to resolve this inconsistency:
1. Restore the netdomain rules as in this change. In that case,
some rules in app.te can be removed as they are redundant with these rules.
-or-
2. Completely remove the netdomain attribute, the net_domain() macro,
and all calls to it. In that case, each domain that requires network
access will need to duplicate these rules or the necessary subset in order
to function.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Change-Id: Ia54f0cd0bbda5c510423b1046626bd50f79ed7b6
This prevents denials from being generated by the base policy.
Over time, these rules will be incrementally tightened to improve
security.
Change-Id: I4be1c987a5d69ac784a56d42fc2c9063c402de11
