platform_system_sepolicy/netd.te
Stephen Smalley 1601132086 Clean up socket rules.
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>
2014-02-25 12:41:23 -05:00

84 lines
2.7 KiB
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# network manager
type netd, domain;
type netd_exec, exec_type, file_type;
init_daemon_domain(netd)
net_domain(netd)
allow netd self:capability { net_admin net_raw kill };
# Note: fsetid is deliberately not included above. fsetid checks are
# triggered by chmod on a directory or file owned by a group other
# than one of the groups assigned to the current process to see if
# the setgid bit should be cleared, regardless of whether the setgid
# bit was even set. We do not appear to truly need this capability
# for netd to operate. Uncomment the dontaudit rule below after
# sufficient testing of the fsetid removal.
# dontaudit netd self:capability fsetid;
allow netd self:netlink_kobject_uevent_socket create_socket_perms;
allow netd self:netlink_route_socket nlmsg_write;
allow netd self:netlink_nflog_socket create_socket_perms;
allow netd shell_exec:file rx_file_perms;
allow netd system_file:file x_file_perms;
allow netd devpts:chr_file rw_file_perms;
# For /proc/sys/net/ipv[46]/route/flush.
allow netd proc_net:file write;
# For /sys/modules/bcmdhd/parameters/firmware_path
# XXX Split into its own type.
allow netd sysfs:file write;
# Set dhcp lease for PAN connection
unix_socket_connect(netd, property, init)
allow netd system_prop:property_service set;
# Connect to PAN
domain_auto_trans(netd, dhcp_exec, dhcp)
allow netd dhcp:process signal;
# Needed to update /data/misc/wifi/hostapd.conf
# TODO: See what we can do to reduce the need for
# these capabilities
allow netd self:capability { dac_override chown fowner };
allow netd wifi_data_file:file create_file_perms;
allow netd wifi_data_file:dir rw_dir_perms;
# Allow netd to spawn hostapd in it's own domain
domain_auto_trans(netd, hostapd_exec, hostapd)
allow netd hostapd:process signal;
# Allow netd to spawn dnsmasq in it's own domain
domain_auto_trans(netd, dnsmasq_exec, dnsmasq)
allow netd dnsmasq:process signal;
# Allow netd to start clatd in its own domain
domain_auto_trans(netd, clatd_exec, clatd)
allow netd clatd:process signal;
# Support netd running mdnsd
# TODO: prune this back further
allow netd ctl_default_prop:property_service set;
###
### Neverallow rules
###
### netd should NEVER do any of this
# Block device access.
neverallow netd dev_type:blk_file { read write };
# Setting SELinux enforcing status or booleans.
neverallow netd kernel:security { setenforce setbool };
# Load security policy.
neverallow netd kernel:security load_policy;
# ptrace any other app
neverallow netd { domain }:process ptrace;
# Write to /system.
neverallow netd system_file:dir_file_class_set write;
# Write to files in /data/data or system files on /data
neverallow netd { app_data_file system_data_file }:dir_file_class_set write;