selinux-policy/policy/mls

ifdef(`enable_mls',`
#
# Define sensitivities 
#
# Domination of sensitivities is in increasin
# numerical order, with s0 being the lowest

gen_sens(mls_num_sens)

#
# Define the categories
#
# Generate declarations

gen_cats(mls_num_cats)

#
# Each MLS level specifies a sensitivity and zero or more categories which may
# be associated with that sensitivity.
#
# Generate levels from all sensitivities
# with all categories

gen_levels(mls_num_sens,mls_num_cats)

#
# Define the MLS policy
#
# mlsconstrain class_set perm_set expression ;
#
# mlsvalidatetrans class_set expression ;
#
# expression : ( expression )
#	     | not expression
#	     | expression and expression
#	     | expression or expression
#	     | u1 op u2
#	     | r1 role_mls_op r2
#	     | t1 op t2
#	     | l1 role_mls_op l2
#	     | l1 role_mls_op h2
#	     | h1 role_mls_op l2
#	     | h1 role_mls_op h2
#	     | l1 role_mls_op h1
#	     | l2 role_mls_op h2
#	     | u1 op names
#	     | u2 op names
#	     | r1 op names
#	     | r2 op names
#	     | t1 op names
#	     | t2 op names
#	     | u3 op names (NOTE: this is only available for mlsvalidatetrans)
#	     | r3 op names (NOTE: this is only available for mlsvalidatetrans)
#	     | t3 op names (NOTE: this is only available for mlsvalidatetrans)
#
# op : == | !=
# role_mls_op : == | != | eq | dom | domby | incomp
#
# names : name | { name_list }
# name_list : name | name_list name
#

#
# MLS policy for the file classes
#

# make sure these file classes are "single level"
mlsconstrain { file lnk_file fifo_file } { create relabelto }
	( l2 eq h2 );

# new file labels must be dominated by the relabeling subjects clearance
mlsconstrain { dir file lnk_file chr_file blk_file sock_file fifo_file } relabelto
	( h1 dom h2 );

# the file "read" ops (note the check is dominance of the low level)
mlsconstrain { dir file lnk_file chr_file blk_file sock_file fifo_file } { read getattr execute }
	(( l1 dom l2 ) or
	 (( t1 == mlsfilereadtoclr ) and ( h1 dom l2 )) or
	 ( t1 == mlsfileread ) or
	 ( t2 == mlstrustedobject ));

mlsconstrain dir search
	(( l1 dom l2 ) or
	 (( t1 == mlsfilereadtoclr ) and ( h1 dom l2 )) or
	 ( t1 == mlsfileread ) or
	 ( t2 == mlstrustedobject ));

# the "single level" file "write" ops
mlsconstrain { file lnk_file fifo_file dir chr_file blk_file sock_file } { write create setattr relabelfrom append unlink link rename mounton }
	(( l1 eq l2 ) or
	 (( t1 == mlsfilewritetoclr ) and ( h1 dom l2 ) and ( l1 domby l2 )) or
	 (( t2 == mlsfilewriteinrange ) and ( l1 dom l2 ) and ( h1 domby h2 )) or
	 ( t1 == mlsfilewrite ) or
	 ( t2 == mlstrustedobject ));

mlsconstrain dir { add_name remove_name reparent rmdir }
	((( l1 dom l2 ) and ( l1 domby h2 )) or
	 (( t1 == mlsfilewritetoclr ) and ( h1 dom l2 ) and ( l1 domby l2 )) or
	 ( t1 == mlsfilewrite ) or
	 ( t2 == mlstrustedobject ));

# these access vectors have no MLS restrictions
# { dir file lnk_file chr_file blk_file sock_file fifo_file } { ioctl lock swapon quotaon }
#
# { file chr_file } { execute_no_trans entrypoint execmod }

# the file upgrade/downgrade rule
mlsvalidatetrans { dir file lnk_file chr_file blk_file sock_file fifo_file }
	((( l1 eq l2 ) or
	  (( t3 == mlsfileupgrade ) and ( l1 domby l2 )) or
	  (( t3 == mlsfiledowngrade ) and ( l1 dom l2 )) or
	  (( t3 == mlsfiledowngrade ) and ( l1 incomp l2 ))) and
	 (( h1 eq h2 ) or
	  (( t3 == mlsfileupgrade ) and ( h1 domby h2 )) or
	  (( t3 == mlsfiledowngrade ) and ( h1 dom h2 )) or
	  (( t3 == mlsfiledowngrade ) and ( h1 incomp h2 ))));

# create can also require the upgrade/downgrade checks if the creating process
# has used setfscreate (note that both the high and low level of the object
# default to the process sensitivity level)
mlsconstrain { dir file lnk_file chr_file blk_file sock_file fifo_file } create
	((( l1 eq l2 ) or
	  (( t1 == mlsfileupgrade ) and ( l1 domby l2 )) or
	  (( t1 == mlsfiledowngrade ) and ( l1 dom l2 )) or
	  (( t1 == mlsfiledowngrade ) and ( l1 incomp l2 ))) and
	 (( l1 eq h2 ) or
	  (( t1 == mlsfileupgrade ) and ( l1 domby h2 )) or
	  (( t1 == mlsfiledowngrade ) and ( l1 dom h2 )) or
	  (( t1 == mlsfiledowngrade ) and ( l1 incomp h2 ))));




#
# MLS policy for the filesystem class
#

# new filesystem labels must be dominated by the relabeling subjects clearance
mlsconstrain filesystem relabelto
	( h1 dom h2 );

# the filesystem "read" ops (implicit single level)
mlsconstrain filesystem { getattr quotaget }
	(( l1 dom l2 ) or
	 (( t1 == mlsfilereadtoclr ) and ( h1 dom l2 )) or
	 ( t1 == mlsfileread ));

# all the filesystem "write" ops (implicit single level)
mlsconstrain filesystem { mount remount unmount relabelfrom quotamod }
	(( l1 eq l2 ) or
	 (( t1 == mlsfilewritetoclr ) and ( h1 dom l2 ) and ( l1 domby l2 )) or
	 ( t1 == mlsfilewrite ));

# these access vectors have no MLS restrictions
# filesystem { transition associate }




#
# MLS policy for the socket classes
#

# new socket labels must be dominated by the relabeling subjects clearance
mlsconstrain { socket tcp_socket udp_socket rawip_socket netlink_socket packet_socket key_socket unix_stream_socket unix_dgram_socket netlink_route_socket netlink_firewall_socket netlink_tcpdiag_socket netlink_nflog_socket netlink_xfrm_socket netlink_selinux_socket netlink_audit_socket netlink_ip6fw_socket netlink_dnrt_socket } relabelto
	( h1 dom h2 );

# the socket "read" ops (note the check is dominance of the low level)
mlsconstrain { socket tcp_socket udp_socket rawip_socket netlink_socket packet_socket key_socket unix_stream_socket unix_dgram_socket netlink_route_socket netlink_firewall_socket netlink_tcpdiag_socket netlink_nflog_socket netlink_xfrm_socket netlink_selinux_socket netlink_audit_socket netlink_ip6fw_socket netlink_dnrt_socket } { read getattr listen accept getopt recv_msg }
	(( l1 dom l2 ) or
	 (( t1 == mlsnetreadtoclr ) and ( h1 dom l2 )) or
	 ( t1 == mlsnetread ));

mlsconstrain { netlink_route_socket netlink_firewall_socket netlink_tcpdiag_socket netlink_xfrm_socket netlink_audit_socket netlink_ip6fw_socket } nlmsg_read
	(( l1 dom l2 ) or
	 (( t1 == mlsnetreadtoclr ) and ( h1 dom l2 )) or
	 ( t1 == mlsnetread ));

# the socket "write" ops
mlsconstrain { socket tcp_socket udp_socket rawip_socket netlink_socket packet_socket key_socket unix_stream_socket unix_dgram_socket netlink_route_socket netlink_firewall_socket netlink_tcpdiag_socket netlink_nflog_socket netlink_xfrm_socket netlink_selinux_socket netlink_audit_socket netlink_ip6fw_socket netlink_dnrt_socket } { write setattr relabelfrom connect setopt shutdown }
	((( l1 dom l2 ) and ( l1 domby h2 )) or
	 (( t1 == mlsnetwritetoclr ) and ( h1 dom l2 ) and ( l1 domby l2 )) or
	 ( t1 == mlsnetwrite ));

# used by netlabel to restrict normal domains to same level connections unless the connection is unlabeled
mlsconstrain { tcp_socket udp_socket rawip_socket } recvfrom
	(( l1 eq l2 ) or
	 (( t1 == mlsnetreadtoclr ) and ( h1 dom l2 )) or
	 ( t1 == mlsnetread ) or
	 ( t2 == unlabeled_t ));

# these access vectors have no MLS restrictions
# { socket tcp_socket udp_socket rawip_socket netlink_socket packet_socket key_socket unix_stream_socket unix_dgram_socket netlink_route_socket netlink_firewall_socket netlink_tcpdiag_socket netlink_nflog_socket netlink_xfrm_socket netlink_selinux_socket netlink_audit_socket netlink_ip6fw_socket netlink_dnrt_socket } { ioctl create lock append bind sendto send_msg name_bind }
#
# { tcp_socket udp_socket rawip_socket } node_bind
#
# { tcp_socket unix_stream_socket } { connectto newconn acceptfrom }
#
# tcp_socket name_connect
#
# { netlink_route_socket netlink_firewall_socket netlink_tcpdiag_socket netlink_xfrm_socket netlink_audit_socket netlink_ip6fw_socket } nlmsg_write
#
# netlink_audit_socket { nlmsg_relay nlmsg_readpriv }
#
# netlink_kobject_uevent_socket *
#




#
# MLS policy for the ipc classes
#

# the ipc "read" ops (implicit single level)
mlsconstrain { ipc sem msgq shm } { getattr read unix_read }
	(( l1 dom l2 ) or
	 (( t1 == mlsipcreadtoclr ) and ( h1 dom l2 )) or
	 ( t1 == mlsipcread ));

mlsconstrain msg receive
	(( l1 dom l2 ) or
	 (( t1 == mlsipcreadtoclr ) and ( h1 dom l2 )) or
	 ( t1 == mlsipcread ));

# the ipc "write" ops (implicit single level)
mlsconstrain { ipc sem msgq shm } { create destroy setattr write unix_write }
	(( l1 eq l2 ) or
	 (( t1 == mlsipcwritetoclr ) and ( h1 dom l2 ) and ( l1 domby l2 )) or
	 ( t1 == mlsipcwrite ));

mlsconstrain msgq enqueue
	(( l1 eq l2 ) or
	 (( t1 == mlsipcwritetoclr ) and ( h1 dom l2 ) and ( l1 domby l2 )) or
	 ( t1 == mlsipcwrite ));

mlsconstrain shm lock
	(( l1 eq l2 ) or
	 (( t1 == mlsipcwritetoclr ) and ( h1 dom l2 ) and ( l1 domby l2 )) or
	 ( t1 == mlsipcwrite ));

mlsconstrain msg send
	(( l1 eq l2 ) or
	 (( t1 == mlsipcwritetoclr ) and ( h1 dom l2 ) and ( l1 domby l2 )) or
	 ( t1 == mlsipcwrite ));

# these access vectors have no MLS restrictions
# { ipc sem msgq shm } associate




#
# MLS policy for the fd class
#

# No sharing of open file descriptors between levels unless
# the process type is authorized to use fds created by 
# other levels (mlsfduse) or the fd type is authorized to
# shared among levels (mlsfdshare). 
mlsconstrain fd use (
	l1 eq l2
	or t1 == mlsfduse
	or t2 == mlsfdshare
);

#
# MLS policy for the network object classes
#

# the netif/node "read" ops (implicit single level socket doing the read)
#                           (note the check is dominance of the low level)
mlsconstrain { node netif } { tcp_recv udp_recv rawip_recv }
	(( l1 dom l2 ) or ( t1 == mlsnetrecvall ));

# the netif/node "write" ops (implicit single level socket doing the write)
mlsconstrain { netif node } { tcp_send udp_send rawip_send }
	(( l1 dom l2 ) and ( l1 domby h2 ));

# these access vectors have no MLS restrictions
# node enforce_dest




#
# MLS policy for the process class
#

# new process labels must be dominated by the relabeling subjects clearance
# and sensitivity level changes require privilege
mlsconstrain process transition
	(( h1 dom h2 ) and
	 (( l1 eq l2 ) or ( t1 == mlsprocsetsl ) or
	  (( t1 == privrangetrans ) and ( t2 == mlsrangetrans ))));
mlsconstrain process dyntransition
	(( h1 dom h2 ) and
	 (( l1 eq l2 ) or ( t1 == mlsprocsetsl )));

# all the process "read" ops
mlsconstrain process { getsched getsession getpgid getcap getattr ptrace share }
	(( l1 dom l2 ) or
	 (( t1 == mlsprocreadtoclr ) and ( h1 dom l2 )) or
	 ( t1 == mlsprocread ));

# all the process "write" ops (note the check is equality on the low level)
mlsconstrain process { sigkill sigstop signal setsched setpgid setcap setexec setfscreate setcurrent ptrace share }
	(( l1 eq l2 ) or
	 (( t1 == mlsprocwritetoclr ) and ( h1 dom l2 ) and ( l1 domby l2 )) or
	 ( t1 == mlsprocwrite ));

# these access vectors have no MLS restrictions
# process { fork sigchld signull noatsecure siginh setrlimit rlimitinh execmem execstack execheap }




#
# MLS policy for the security class
#

# these access vectors have no MLS restrictions
# security *




#
# MLS policy for the system class
#

# these access vectors have no MLS restrictions
# system *




#
# MLS policy for the capability class
#

# these access vectors have no MLS restrictions
# capability *




#
# MLS policy for the passwd class
#

# these access vectors have no MLS restrictions
# passwd *




#
# MLS policy for the drawable class
#

# the drawable "read" ops (implicit single level)
mlsconstrain drawable { getattr copy }
	(( l1 dom l2 ) or
	 (( t1 == mlsxwinreadtoclr ) and ( h1 dom l2 )) or
	 ( t1 == mlsxwinread ));

# the drawable "write" ops (implicit single level)
mlsconstrain drawable { create destroy draw copy }
	(( l1 eq l2 ) or
	 (( t1 == mlsxwinwritetoclr ) and ( h1 dom l2 ) and ( l1 domby l2 )) or
	 ( t1 == mlsxwinwrite ));




#
# MLS policy for the gc class
#

# the gc "read" ops (implicit single level)
mlsconstrain gc getattr
	(( l1 dom l2 ) or
	 (( t1 == mlsxwinreadtoclr ) and ( h1 dom l2 )) or
	 ( t1 == mlsxwinread ));

# the gc "write" ops (implicit single level)
mlsconstrain gc { create free setattr }
	(( l1 eq l2 ) or
	 (( t1 == mlsxwinwritetoclr ) and ( h1 dom l2 ) and ( l1 domby l2 )) or
	 ( t1 == mlsxwinwrite ));




#
# MLS policy for the window class
#

# the window "read" ops (implicit single level)
mlsconstrain window { listprop getattr enumerate mousemotion inputevent drawevent windowchangeevent windowchangerequest serverchangeevent extensionevent }
	(( l1 dom l2 ) or
	 (( t1 == mlsxwinreadtoclr ) and ( h1 dom l2 )) or
	 ( t1 == mlsxwinread ));

# the window "write" ops (implicit single level)
mlsconstrain window { addchild create destroy chstack chproplist chprop setattr setfocus move chselection chparent ctrllife transparent clientcomevent }
	(( l1 eq l2 ) or
	 (( t1 == mlsxwinwritetoclr ) and ( h1 dom l2 ) and ( l1 domby l2 )) or
	 ( t1 == mlsxwinwrite ) or
	 ( t2 == mlstrustedobject ));

# these access vectors have no MLS restrictions
# window { map unmap }




#
# MLS policy for the font class
#

# the font "read" ops (implicit single level)
mlsconstrain font { load getattr }
	(( l1 dom l2 ) or
	 (( t1 == mlsxwinreadtoclr ) and ( h1 dom l2 )) or
	 ( t1 == mlsxwinread ));

# the font "write" ops (implicit single level)
mlsconstrain font free
	(( l1 eq l2 ) or
	 (( t1 == mlsxwinwritetoclr ) and ( h1 dom l2 ) and ( l1 domby l2 )) or
	 ( t1 == mlsxwinwrite ));

# these access vectors have no MLS restrictions
# font use




#
# MLS policy for the colormap class
#

# the colormap "read" ops (implicit single level)
mlsconstrain colormap { list read getattr }
	(( l1 dom l2 ) or
	 (( t1 == mlsxwinreadtoclr ) and ( h1 dom l2 )) or
	 ( t1 == mlsxwinreadcolormap ) or
	 ( t1 == mlsxwinread ));

# the colormap "write" ops (implicit single level)
mlsconstrain colormap { create free install uninstall store setattr }
	(( l1 eq l2 ) or
	 (( t1 == mlsxwinwritetoclr ) and ( h1 dom l2 ) and ( l1 domby l2 )) or
	 ( t1 == mlsxwinwritecolormap ) or
	 ( t1 == mlsxwinwrite ));




#
# MLS policy for the property class
#

# the property "read" ops (implicit single level)
mlsconstrain property { read }
	(( l1 dom l2 ) or
	 (( t1 == mlsxwinreadtoclr ) and ( h1 dom l2 )) or
	 ( t1 == mlsxwinreadproperty ) or
	 ( t1 == mlsxwinread ));

# the property "write" ops (implicit single level)
mlsconstrain property { create free write }
	(( l1 eq l2 ) or
	 (( t1 == mlsxwinwritetoclr ) and ( h1 dom l2 ) and ( l1 domby l2 )) or
	 ( t1 == mlsxwinwriteproperty ) or
	 ( t1 == mlsxwinwrite ));




#
# MLS policy for the cursor class
#

# the cursor "write" ops (implicit single level)
mlsconstrain cursor { create createglyph free assign setattr }
	(( l1 eq l2 ) or
	 (( t1 == mlsxwinwritetoclr ) and ( h1 dom l2 ) and ( l1 domby l2 )) or
	 ( t1 == mlsxwinwrite ));




#
# MLS policy for the xclient class
#

# the xclient "write" ops (implicit single level)
mlsconstrain xclient kill
	(( l1 eq l2 ) or
	 (( t1 == mlsxwinwritetoclr ) and ( h1 dom l2 ) and ( l1 domby l2 )) or
	 ( t1 == mlsxwinwrite ));




#
# MLS policy for the xinput class
#

# these access vectors have no MLS restrictions
# xinput ~{ relabelinput setattr }

# the xinput "write" ops (implicit single level)
mlsconstrain xinput { setattr relabelinput }
	(( l1 eq l2 ) or
	 (( t1 == mlsxwinwritetoclr ) and ( h1 dom l2 ) and ( l1 domby l2 )) or
	 ( t1 == mlsxwinwritexinput ) or
	 ( t1 == mlsxwinwrite ));




#
# MLS policy for the xserver class
#

# these access vectors have no MLS restrictions
# xserver *




#
# MLS policy for the xextension class
#

# these access vectors have no MLS restrictions
# xextension { query use }


#
# MLS policy for the pax class
#

# these access vectors have no MLS restrictions
# pax { pageexec emutramp mprotect randmmap randexec segmexec }




#
# MLS policy for the dbus class
#

# these access vectors have no MLS restrictions
# dbus { acquire_svc send_msg }




#
# MLS policy for the nscd class
#

# these access vectors have no MLS restrictions
# nscd { getpwd getgrp gethost getstat admin shmempwd shmemgrp shmemhost }




#
# MLS policy for the association class
#

mlsconstrain association { recvfrom }
	((( l1 dom l2 ) and ( l1 domby h2 )) or
	 (( t1 == mlsnetreadtoclr ) and ( h1 dom l2 )) or
	 ( t1 == mlsnetread ) or
	 ( t2 == unlabeled_t ));

mlsconstrain association { sendto }
	((( l1 dom l2 ) and ( l1 domby h2 )) or
	 ( t2 == unlabeled_t ));

mlsconstrain association { polmatch }
	(( l1 dom l2 ) and ( h1 domby h2 ));



#
# MLS policy for the context class
#

mlsconstrain context translate
	(( h1 dom h2 ) or ( t1 == mlstranslate ));

mlsconstrain context contains
	( h1 dom h2 );

#
# MLS policy for database classes
#

# make sure these database classes are "single level"
mlsconstrain { db_database db_table db_procedure db_column db_blob } { create relabelto }
	( l2 eq h2 );
mlsconstrain { db_tuple } { insert relabelto }
	( l2 eq h2 );

# new database labels must be dominated by the relabeling subjects clearance
mlsconstrain { db_database db_table db_procedure db_column db_tuple db_blob } { relabelto }
	( h1 dom h2 );

# the database "read" ops (note the check is dominance of the low level)
mlsconstrain { db_database } { getattr access get_param }
	(( l1 dom l2 ) or
	 (( t1 == mlsdbreadtoclr ) and ( h1 dom l2 )) or
	 ( t1 == mlsdbread ) or
	 ( t2 == mlstrustedobject ));

mlsconstrain { db_table db_column } { getattr use select }
	(( l1 dom l2 ) or
	 (( t1 == mlsdbreadtoclr ) and ( h1 dom l2 )) or
	 ( t1 == mlsdbread ) or
	 ( t2 == mlstrustedobject ));

mlsconstrain { db_procedure } { getattr execute }
	(( l1 dom l2 ) or
	 (( t1 == mlsdbreadtoclr ) and ( h1 dom l2 )) or
	 ( t1 == mlsdbread ) or
	 ( t2 == mlstrustedobject ));

mlsconstrain { db_blob } { getattr read }
	(( l1 dom l2 ) or
	 (( t1 == mlsdbreadtoclr ) and ( h1 dom l2 )) or
	 ( t1 == mlsdbread ) or
	 ( t2 == mlstrustedobject ));

mlsconstrain { db_tuple } { use select }
	(( l1 dom l2 ) or
	 (( t1 == mlsdbreadtoclr ) and ( h1 dom l2 )) or
	 ( t1 == mlsdbread ) or
	 ( t2 == mlstrustedobject ));

# the "single level" file "write" ops
mlsconstrain { db_database } { create drop setattr relabelfrom install_module load_module set_param }
	(( l1 eq l2 ) or
	 (( t1 == mlsdbwritetoclr ) and ( h1 dom l2 ) and ( l1 domby l2 )) or
	 (( t2 == mlsdbwriteinrange ) and ( l1 dom l2 ) and ( h1 domby h2 )) or
	 ( t1 == mlsdbwrite ) or
	 ( t2 == mlstrustedobject ));

mlsconstrain { db_table } { create drop setattr relabelfrom update insert delete lock }
	(( l1 eq l2 ) or
	 (( t1 == mlsdbwritetoclr ) and ( h1 dom l2 ) and ( l1 domby l2 )) or
	 (( t2 == mlsdbwriteinrange ) and ( l1 dom l2 ) and ( h1 domby h2 )) or
	 ( t1 == mlsdbwrite ) or
	 ( t2 == mlstrustedobject ));

mlsconstrain { db_column } { create drop setattr relabelfrom update insert }
	(( l1 eq l2 ) or
	 (( t1 == mlsdbwritetoclr ) and ( h1 dom l2 ) and ( l1 domby l2 )) or
	 (( t2 == mlsdbwriteinrange ) and ( l1 dom l2 ) and ( h1 domby h2 )) or
	 ( t1 == mlsdbwrite ) or
	 ( t2 == mlstrustedobject ));

mlsconstrain { db_blob } { create drop setattr relabelfrom write import export }
	(( l1 eq l2 ) or
	 (( t1 == mlsdbwritetoclr ) and ( h1 dom l2 ) and ( l1 domby l2 )) or
	 (( t2 == mlsdbwriteinrange ) and ( l1 dom l2 ) and ( h1 domby h2 )) or
	 ( t1 == mlsdbwrite ) or
	 ( t2 == mlstrustedobject ));

mlsconstrain { db_tuple } { relabelfrom update insert delete }
	(( l1 eq l2 ) or
	 (( t1 == mlsdbwritetoclr ) and ( h1 dom l2 ) and ( l1 domby l2 )) or
	 (( t2 == mlsdbwriteinrange ) and ( l1 dom l2 ) and ( h1 domby h2 )) or
	 ( t1 == mlsdbwrite ) or
	 ( t2 == mlstrustedobject ));

# the database upgrade/downgrade rule
mlsvalidatetrans { db_database db_table db_procedure db_column db_tuple db_blob }
	((( l1 eq l2 ) or
	  (( t3 == mlsdbupgrade ) and ( l1 domby l2 )) or
	  (( t3 == mlsdbdowngrade ) and ( l1 dom l2 )) or
	  (( t3 == mlsdbdowngrade ) and ( l1 incomp l2 ))) and
	 (( l1 eq h2 ) or
	  (( t3 == mlsdbupgrade ) and ( h1 domby h2 )) or
	  (( t3 == mlsdbdowngrade ) and ( h1 dom h2 )) or
	  (( t3 == mlsdbdowngrade ) and ( h1 incomp h2 ))));

') dnl end enable_mls