apparmor: refcount the pdb

With the move to permission tables the dfa is no longer a stand
alone entity when used, needing a minimum of a permission table.
However it still could be shared among different pdbs each using
a different permission table.

Instead of duping the permission table when sharing a pdb, add a
refcount to the pdb so it can be easily shared.

Reviewed-by: Georgia Garcia <georgia.garcia@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: fixup return comments for kernel doc cleanups by Gaosheng Cui

[PATCH -next 05/11] apparmor: Fix kernel-doc warnings in apparmor/label.c
missed updating the Returns comment for the new parameter names

[PATCH -next 05/11] apparmor: Fix kernel-doc warnings in apparmor/label.c
Added the @size parameter comment without mentioning it is a return
value.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: Fix kernel-doc warnings in apparmor/label.c

Fix kernel-doc warnings:

security/apparmor/label.c:166: warning: Excess function parameter
'n' description in 'vec_cmp'
security/apparmor/label.c:166: warning: Excess function parameter
'vec' description in 'vec_cmp'
security/apparmor/label.c:166: warning: Function parameter or member
'an' not described in 'vec_cmp'
security/apparmor/label.c:166: warning: Function parameter or member
'bn' not described in 'vec_cmp'
security/apparmor/label.c:166: warning: Function parameter or member
'b' not described in 'vec_cmp'
security/apparmor/label.c:2051: warning: Function parameter or member
'label' not described in '__label_update'
security/apparmor/label.c:266: warning: Function parameter or member
'flags' not described in 'aa_vec_unique'
security/apparmor/label.c:594: warning: Excess function parameter
'l' description in '__label_remove'
security/apparmor/label.c:594: warning: Function parameter or member
'label' not described in '__label_remove'
security/apparmor/label.c:929: warning: Function parameter or member
'label' not described in 'aa_label_insert'
security/apparmor/label.c:929: warning: Function parameter or member
'ls' not described in 'aa_label_insert'
security/apparmor/label.c:1221: warning: Excess function parameter
'ls' description in 'aa_label_merge'
security/apparmor/label.c:1302: warning: Excess function parameter
'start' description in 'label_compound_match'
security/apparmor/label.c:1302: warning: Function parameter or member
'rules' not described in 'label_compound_match'
security/apparmor/label.c:1302: warning: Function parameter or member
'state' not described in 'label_compound_match'
security/apparmor/label.c:2051: warning: Function parameter or member
'label' not described in '__label_update'

Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: remove useless static inline functions

Remove the following useless static inline functions:

1. label_is_visible() is a static function in
security/apparmor/label.c, and it's not used, aa_ns_visible()
can do the same things as it, so it's redundant.

2. is_deleted() is a static function in security/apparmor/file.c,
and it's not used since commit aebd873e8d3e ("apparmor: refactor
path name lookup and permission checks around labels"), so it's
redundant.

They are redundant, so remove them.

Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: Fix regression in stacking due to label flags

The unconfined label flag is not being computed correctly. It
should only be set if all the profiles in the vector are set, which
is different than what is required for the debug and stale flag
that are set if any on the profile flags are set.

Fixes: c1ed5da19765 ("apparmor: allow label to carry debug flags")
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: refactor profile rules and attachments

In preparation for moving from a single set of rules and a single
attachment to multiple rulesets and attachments separate from the
profile refactor attachment information and ruleset info into their
own structures.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: preparse for state being more than just an integer

Convert from an unsigned int to a state_t for state position. This is
a step in prepping for the state position carrying some additional
flags, and a limited form of backtracking to support variables.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: convert policy lookup to use accept as an index

Remap polidydb dfa accept table from embedded perms to an index, and
then move the perm lookup to use the accept entry as an index into the
perm table. This is done so that the perm table can be separated from
the dfa, allowing dfa accept to index to share expanded permission
sets.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: compute policydb permission on profile load

Rather than computing policydb permissions for each access
permissions can be computed once on profile load and stored for lookup.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: allow label to carry debug flags

Allow labels to have debug flags that can be used to trigger debug output
only from profiles/labels that are marked. This can help reduce debug
output by allowing debug to be target to a specific confinement condition.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: fix aa_label_asxprint return check

Clang static analysis reports this issue
label.c:1802:3: warning: 2nd function call argument
is an uninitialized value
pr_info("%s", str);
^~~~~~~~~~~~~~~~~~

str is set from a successful call to aa_label_asxprint(&str, ...)
On failure a negative value is returned, not a -1. So change
the check.

Fixes: f1bd904175e8 ("apparmor: add the base fns() for domain labels")
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: Fix kernel-doc

Fix function name in security/apparmor/label.c, policy.c, procattr.c
kernel-doc comment to remove some warnings found by clang(make W=1 LLVM=1).

security/apparmor/label.c:499: warning: expecting prototype for
aa_label_next_not_in_set(). Prototype was for
__aa_label_next_not_in_set() instead
security/apparmor/label.c:2147: warning: expecting prototype for
__aa_labelset_udate_subtree(). Prototype was for
__aa_labelset_update_subtree() instead

security/apparmor/policy.c:434: warning: expecting prototype for
aa_lookup_profile(). Prototype was for aa_lookupn_profile() instead

security/apparmor/procattr.c:101: warning: expecting prototype for
aa_setprocattr_chagnehat(). Prototype was for aa_setprocattr_changehat()
instead

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: fix absroot causing audited secids to begin with =

AppArmor is prefixing secids that are converted to secctx with the =
to indicate the secctx should only be parsed from an absolute root
POV. This allows catching errors where secctx are reparsed back into
internal labels.

Unfortunately because audit is using secid to secctx conversion this
means that subject and object labels can result in a very unfortunate
== that can break audit parsing.

eg. the subj==unconfined term in the below audit message

type=USER_LOGIN msg=audit(1639443365.233:160): pid=1633 uid=0 auid=1000
ses=3 subj==unconfined msg='op=login id=1000 exe="/usr/sbin/sshd"
hostname=192.168.122.1 addr=192.168.122.1 terminal=/dev/pts/1 res=success'

Fix this by switch the prepending of = to a _. This still works as a
special character to flag this case without breaking audit. Also move
this check behind debug as it should not be needed during normal
operqation.

Fixes: 26b7899510ae ("apparmor: add support for absolute root view based labels")
Reported-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: Use struct_size() helper in kzalloc()

Make use of the struct_size() helper instead of an open-coded version,
in order to avoid any potential type mistakes or integer overflows that,
in the worse scenario, could lead to heap overflows.

Link: https://github.com/KSPP/linux/issues/160
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: fix error check

clang static analysis reports this representative problem:

label.c:1463:16: warning: Assigned value is garbage or undefined
label->hname = name;
^ ~~~~

In aa_update_label_name(), this the problem block of code

if (aa_label_acntsxprint(&name, ...) == -1)
return res;

On failure, aa_label_acntsxprint() has a more complicated return
that just -1. So check for a negative return.

It was also noted that the aa_label_acntsxprint() main comment refers
to a nonexistent parameter, so clean up the comment.

Fixes: f1bd904175e8 ("apparmor: add the base fns() for domain labels")
Signed-off-by: Tom Rix <trix@redhat.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: fix introspection of of task mode for unconfined tasks

Fix two issues with introspecting the task mode.

1. If a task is attached to a unconfined profile that is not the
ns->unconfined profile then. Mode the mode is always reported
as -

$ ps -Z
LABEL PID TTY TIME CMD
unconfined 1287 pts/0 00:00:01 bash
test (-) 1892 pts/0 00:00:00 ps

instead of the correct value of (unconfined) as shown below

$ ps -Z
LABEL PID TTY TIME CMD
unconfined 2483 pts/0 00:00:01 bash
test (unconfined) 3591 pts/0 00:00:00 ps

2. if a task is confined by a stack of profiles that are unconfined
the output of label mode is again the incorrect value of (-) like
above, instead of (unconfined). This is because the visibile
profile count increment is skipped by the special casing of
unconfined.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: Fix memory leak of profile proxy

When the proxy isn't replaced and the profile is removed, the proxy
is being leaked resulting in a kmemleak check message of

unreferenced object 0xffff888077a3a490 (size 16):
comm "apparmor_parser", pid 128041, jiffies 4322684109 (age 1097.028s)
hex dump (first 16 bytes):
03 00 00 00 00 00 00 00 b0 92 fd 4b 81 88 ff ff ...........K....
backtrace:
[<0000000084d5daf2>] aa_alloc_proxy+0x58/0xe0
[<00000000ecc0e21a>] aa_alloc_profile+0x159/0x1a0
[<000000004cc9ce15>] unpack_profile+0x275/0x1c40
[<000000007332b3ca>] aa_unpack+0x1e7/0x7e0
[<00000000e25e31bd>] aa_replace_profiles+0x18a/0x1d10
[<00000000350d9415>] policy_update+0x237/0x650
[<000000003fbf934e>] profile_load+0x122/0x160
[<0000000047f7b781>] vfs_write+0x139/0x290
[<000000008ad12358>] ksys_write+0xcd/0x170
[<000000001a9daa7b>] do_syscall_64+0x70/0x310
[<00000000b9efb0cf>] entry_SYSCALL_64_after_hwframe+0x49/0xb3

Make sure to cleanup the profile's embedded label which will result
on the proxy being properly freed.

Fixes: 637f688dc3dc ("apparmor: switch from profiles to using labels on contexts")
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: fix introspection of of task mode for unconfined tasks

Fix two issues with introspecting the task mode.

1. If a task is attached to a unconfined profile that is not the
ns->unconfined profile then. Mode the mode is always reported
as -

$ ps -Z
LABEL PID TTY TIME CMD
unconfined 1287 pts/0 00:00:01 bash
test (-) 1892 pts/0 00:00:00 ps

instead of the correct value of (unconfined) as shown below

$ ps -Z
LABEL PID TTY TIME CMD
unconfined 2483 pts/0 00:00:01 bash
test (unconfined) 3591 pts/0 00:00:00 ps

2. if a task is confined by a stack of profiles that are unconfined
the output of label mode is again the incorrect value of (-) like
above, instead of (unconfined). This is because the visibile
profile count increment is skipped by the special casing of
unconfined.

Fixes: f1bd904175e8 ("apparmor: add the base fns() for domain labels")
Signed-off-by: John Johansen <john.johansen@canonical.com>

security/apparmor/label.c: Clean code by removing redundant instructions

Previously 'label->proxy->label' value checking
and conditional reassigning were done twice in the same function.
The second one is redundant and can be removed.

Signed-off-by: Mateusz Nosek <mateusznosek0@gmail.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: fix nnp subset test for unconfined

The subset test is not taking into account the unconfined exception
which will cause profile transitions in the stacked confinement
case to fail when no_new_privs is applied.

This fixes a regression introduced in the fix for
https://bugs.launchpad.net/bugs/1839037

BugLink: https://bugs.launchpad.net/bugs/1844186
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: Replace two seq_printf() calls by seq_puts() in aa_label_seq_xprint()

Two strings which did not contain a data format specification should be put
into a sequence. Thus use the corresponding function “seq_puts”.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: fix unsigned len comparison with less than zero

The sanity check in macro update_for_len checks to see if len
is less than zero, however, len is a size_t so it can never be
less than zero, so this sanity check is a no-op. Fix this by
making len a ssize_t so the comparison will work and add ulen
that is a size_t copy of len so that the min() macro won't
throw warnings about comparing different types.

Addresses-Coverity: ("Macro compares unsigned to 0")
Fixes: f1bd904175e8 ("apparmor: add the base fns() for domain labels")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

locking/lockdep: Rename lockdep_assert_held_exclusive() -> lockdep_assert_held_write()

All callers of lockdep_assert_held_exclusive() use it to verify the
correct locking state of either a semaphore (ldisc_sem in tty,
mmap_sem for perf events, i_rwsem of inode for dax) or rwlock by
apparmor. Thus it makes sense to rename _exclusive to _write since
that's the semantics callers care. Additionally there is already
lockdep_assert_held_read(), which this new naming is more consistent with.

No functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190531100651.3969-1-nborisov@suse.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 441

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation version 2 of the license

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 315 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Armijn Hemel <armijn@tjaldur.nl>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190531190115.503150771@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

apparmor: fixup secid map conversion to using IDR

The IDR conversion did not handle an error case for when allocating a
mapping fails, and it did not ensure that mappings did not allocate or
use a 0 value, which is used as an invalid secid. Which is used when a
mapping fails.

Fixes: 3ae7eb49a2be ("apparmor: Use an IDR to allocate apparmor secids")
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: fix typo "replace"

Signed-off-by: Zygmunt Krynicki <zygmunt.krynicki@canonical.com>
Acked-by: Christian Boltz <apparmor@cboltz.de>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: fix typo "comparison"

Signed-off-by: Zygmunt Krynicki <zygmunt.krynicki@canonical.com>
Acked-by: Christian Boltz <apparmor@cboltz.de>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: add support for mapping secids and using secctxes

Use a radix tree to provide a map between the secid and the label,
and along with it a basic ability to provide secctx conversion.

Shared/cached secctx will be added later.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: move context.h to cred.h

Now that file contexts have been moved into file, and task context
fns() and data have been split from the context, only the cred context
remains in context.h so rename to cred.h to better reflect what it
deals with.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: root view labels should not be under user control

The root view of the label parse should not be exposed to user
control.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>

apparmor: provide a bounded version of label_parse

some label/context sources might not be guaranteed to be null terminiated
provide a size bounded version of label parse to deal with these.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>

apparmor: use the dfa to do label parse string splitting

The current split scheme is actually wrong in that it splits
///&

where that is invalid and should fail. Use the dfa to do a proper
bounded split without having to worry about getting the string
processing right in code.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>

apparmor: fix possible recursive lock warning in __aa_create_ns

Use mutex_lock_nested to provide lockdep the parent child lock ordering of
the tree.

This fixes the lockdep Warning
[ 305.275177] ============================================
[ 305.275178] WARNING: possible recursive locking detected
[ 305.275179] 4.14.0-rc7+ #320 Not tainted
[ 305.275180] --------------------------------------------
[ 305.275181] apparmor_parser/1339 is trying to acquire lock:
[ 305.275182] (&ns->lock){+.+.}, at: [<ffffffff970544dd>] __aa_create_ns+0x6d/0x1e0
[ 305.275187]
but task is already holding lock:
[ 305.275187] (&ns->lock){+.+.}, at: [<ffffffff97054b5d>] aa_prepare_ns+0x3d/0xd0
[ 305.275190]
other info that might help us debug this:
[ 305.275191] Possible unsafe locking scenario:

[ 305.275192] CPU0
[ 305.275193] ----
[ 305.275193] lock(&ns->lock);
[ 305.275194] lock(&ns->lock);
[ 305.275195]
*** DEADLOCK ***

[ 305.275196] May be due to missing lock nesting notation

[ 305.275198] 2 locks held by apparmor_parser/1339:
[ 305.275198] #0: (sb_writers#10){.+.+}, at: [<ffffffff96e9c6b7>] vfs_write+0x1a7/0x1d0
[ 305.275202] #1: (&ns->lock){+.+.}, at: [<ffffffff97054b5d>] aa_prepare_ns+0x3d/0xd0
[ 305.275205]
stack backtrace:
[ 305.275207] CPU: 1 PID: 1339 Comm: apparmor_parser Not tainted 4.14.0-rc7+ #320
[ 305.275208] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.1-1ubuntu1 04/01/2014
[ 305.275209] Call Trace:
[ 305.275212] dump_stack+0x85/0xcb
[ 305.275214] __lock_acquire+0x141c/0x1460
[ 305.275216] ? __aa_create_ns+0x6d/0x1e0
[ 305.275218] ? ___slab_alloc+0x183/0x540
[ 305.275219] ? ___slab_alloc+0x183/0x540
[ 305.275221] lock_acquire+0xed/0x1e0
[ 305.275223] ? lock_acquire+0xed/0x1e0
[ 305.275224] ? __aa_create_ns+0x6d/0x1e0
[ 305.275227] __mutex_lock+0x89/0x920
[ 305.275228] ? __aa_create_ns+0x6d/0x1e0
[ 305.275230] ? trace_hardirqs_on_caller+0x11f/0x190
[ 305.275231] ? __aa_create_ns+0x6d/0x1e0
[ 305.275233] ? __lockdep_init_map+0x57/0x1d0
[ 305.275234] ? lockdep_init_map+0x9/0x10
[ 305.275236] ? __rwlock_init+0x32/0x60
[ 305.275238] mutex_lock_nested+0x1b/0x20
[ 305.275240] ? mutex_lock_nested+0x1b/0x20
[ 305.275241] __aa_create_ns+0x6d/0x1e0
[ 305.275243] aa_prepare_ns+0xc2/0xd0
[ 305.275245] aa_replace_profiles+0x168/0xf30
[ 305.275247] ? __might_fault+0x85/0x90
[ 305.275250] policy_update+0xb9/0x380
[ 305.275252] profile_load+0x7e/0x90
[ 305.275254] __vfs_write+0x28/0x150
[ 305.275256] ? rcu_read_lock_sched_held+0x72/0x80
[ 305.275257] ? rcu_sync_lockdep_assert+0x2f/0x60
[ 305.275259] ? __sb_start_write+0xdc/0x1c0
[ 305.275261] ? vfs_write+0x1a7/0x1d0
[ 305.275262] vfs_write+0xca/0x1d0
[ 305.275264] ? trace_hardirqs_on_caller+0x11f/0x190
[ 305.275266] SyS_write+0x49/0xa0
[ 305.275268] entry_SYSCALL_64_fastpath+0x23/0xc2
[ 305.275271] RIP: 0033:0x7fa6b22e8c74
[ 305.275272] RSP: 002b:00007ffeaaee6288 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[ 305.275273] RAX: ffffffffffffffda RBX: 00007ffeaaee62a4 RCX: 00007fa6b22e8c74
[ 305.275274] RDX: 0000000000000a51 RSI: 00005566a8198c10 RDI: 0000000000000004
[ 305.275275] RBP: 0000000000000a39 R08: 0000000000000a51 R09: 0000000000000000
[ 305.275276] R10: 0000000000000000 R11: 0000000000000246 R12: 00005566a8198c10
[ 305.275277] R13: 0000000000000004 R14: 00005566a72ecb88 R15: 00005566a72ec3a8

Fixes: 73688d1ed0b8 ("apparmor: refactor prepare_ns() and make usable from different views")
Signed-off-by: John Johansen <john.johansen@canonical.com>

locking/rwsem, security/apparmor: Replace homebrew use of write_can_lock() with lockdep

The lockdep subsystem provides a robust way to assert that a lock is
held, so use that instead of write_can_lock, which can give incorrect
results for qrwlocks.

Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: John Johansen <john.johansen@canonical.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: paulmck@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1507055129-12300-1-git-send-email-will.deacon@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

apparmor: fix incorrect type assignment when freeing proxies

sparse reports

poisoning the proxy->label before freeing the struct is resulting in
a sparse build warning.
../security/apparmor/label.c:52:30: warning: incorrect type in assignment (different address spaces)
../security/apparmor/label.c:52:30: expected struct aa_label [noderef] <asn:4>*label
../security/apparmor/label.c:52:30: got struct aa_label *<noident>

fix with RCU_INIT_POINTER as this is one of those cases where
rcu_assign_pointer() is not needed.

Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: add support for absolute root view based labels

With apparmor policy virtualization based on policy namespace View's
we don't generally want/need absolute root based views, however there
are cases like debugging and some secid based conversions where
using a root based view is important.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>

apparmor: cleanup conditional check for label in label_print

Signed-off-by: John Johansen <john.johansen@canonical.com>
Acked-by: Seth Arnold <seth.arnold@canonical.com>

apparmor: Redundant condition: prev_ns. in [label.c:1498]

Reported-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: John Johansen <john.johansen@canonical.com>

apparmor: add the base fns() for domain labels

Begin moving apparmor to using broader domain labels, that will allow
run time computation of domain type splitting via "stacking" of
profiles into a domain label vec.

Signed-off-by: John Johansen <john.johansen@canonical.com>