in various kernel objects to represent security data, we embed a
(struct label *) pointer, which now references labels allocated using
a UMA zone (mac_label.c). This allows the size and shape of struct
label to be varied without changing the size and shape of these kernel
objects, which become part of the frozen ABI with 5-STABLE. This opens
the door for boot-time selection of the number of label slots, and hence
changes to the bound on the number of simultaneous labeled policies
at boot-time instead of compile-time. This also makes it easier to
embed label references in new objects as required for locking/caching
with fine-grained network stack locking, such as inpcb structures.
This change also moves us further in the direction of hiding the
structure of kernel objects from MAC policy modules, not to mention
dramatically reducing the number of '&' symbols appearing in both the
MAC Framework and MAC policy modules, and improving readability.
While this results in minimal performance change with MAC enabled, it
will observably shrink the size of a number of critical kernel data
structures for the !MAC case, and should have a small (but measurable)
performance benefit (i.e., struct vnode, struct socket) do to memory
conservation and reduced cost of zeroing memory.
NOTE: Users of MAC must recompile their kernel and all MAC modules as a
result of this change. Because this is an API change, third party
MAC modules will also need to be updated to make less use of the '&'
symbol.
Suggestions from: bmilekic
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
successfully initialized in the label as a socket peer label, not a
socket label. For current policy modules, this didn't make a
difference, but if a policy module had label data in the peer label
that was to be GC'd in a different way than the normal socket label,
it might have been a problem.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
if_xname, if_dname, and if_dunit. if_xname is the name of the interface
and if_dname/unit are the driver name and instance.
This change paves the way for interface renaming and enhanced pseudo
device creation and configuration symantics.
Approved By: re (in principle)
Reviewed By: njl, imp
Tested On: i386, amd64, sparc64
Obtained From: NetBSD (if_xname)
type, rather than "object_label" as the first argument. This reduces
complexity a little for the consumer, and also makes it easier for
use to rename the underlying entry points in struct mac_policy_obj.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
Include src/sys/security/mac/mac_internal.h in kern_mac.c.
Remove redundant defines from the include: SYSCTL_DECL(), debug macros,
composition macros.
Unstaticize various bits now exposed to the remainder of the kernel:
mac_init_label(), mac_destroy_label().
Remove all the functions now implemented in mac_process/mac_vfs/mac_net/
mac_pipe. Also remove debug counters, sysctls exporting debug
counters, enforcement flags, sysctls exporting enforcement flags.
Leave module declaration, sysctl nodes, mactemp malloc type, system
calls.
This should conclude MAC/LINT/NOTES breakage from the break-out process,
but I'm running builds now to make sure I caught everything.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
Unstaticize mac_late.
Remove ea_warn_once, now in mac_vfs.c.
Unstaticisize mac_policy_list, mac_static_policy_list, use
struct mac_policy_list_head instead of LIST_HEAD() directly.
Unstaticize and un-inline MAC policy locking functions so they can
be referenced from mac_*.c.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
Extended attribute transaction warning flag if transactions aren't
supported on the EA implementation being used.
Debug fallback flag to permit a less conservative fallback if reading
an on-disk label fails.
Enforce_fs toggle to enforce file systme access control.
Debugging counters for file system objects: mounts, vnodes, devfs_dirents.
Object initialization, destruction, copying, internalization,
externalization, relabeling for file system objects.
Life cycle operations for devfs entries.
Generic extended attribute label implementation for use by UFS, UFS2 in
multilabel mode.
Generic single-level label implementation for use by all file systems
when in singlelabel mode.
Exec-time transition based on file label entry points.
Vnode operation access control checks (many).
Mount operation access control checks (few).
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
Pipe enforcement flag.
Pipe object debugging counters.
MALLOC type for MAC label storage.
Pipe MAC label management routines, externalize/internalization/change
routines.
Pipe MAC access control checks.
Un-staticize functions called from mac_set_fd() when operating on a
pipe. Abstraction improvements in this space seem likely.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
Network and socket enforcement toggles.
Counters for network objects (mbufs, ifnets, bpfdecs, sockets, and ipqs).
Label management routines for network objects.
Life cycle events for network objects.
Label internalization/externalization/relabel for ifnets, sockets,
including ioctl implementations for sockets, ifnets.
Access control checks relating to network obejcts.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
in mac_internal.h:
Sysctl tree declarations.
Policy list structure definition.
Policy list variables (static, dynamic).
mac_late flag.
Enforcement flags for process, vm, which have checks in multiple files.
mac_labelmbufs variable to drive conditional mbuf labeling.
M_MACTEMP malloc type.
Debugging counter macros.
MAC Framework infrastructure primitives, including policy locking
primitives, kernel label initialization/destruction, userland
label consistency checks, policy slot allocation.
Per-object interfaces for objects that are internalized and externalized
using system calls that will remain centrally defined: credentials,
pipes, vnodes.
MAC policy composition macros: MAC_CHECK, MAC_BOOLEAN, MAC_EXTERNALIZE,
MAC_INTERNALIZE, MAC_PERFORM.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
line up the function names in an earlier generation of the API when
some of the functions returned structure pointers.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
mac_reflect_mbuf_icmp()
mac_reflect_mbuf_tcp()
These entry points permit MAC policies to do "update in place"
changes to the labels on ICMP and TCP mbuf headers when an ICMP or
TCP response is generated to a packet outside of the context of
an existing socket. For example, in respond to a ping or a RST
packet to a SYN on a closed port.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
change in mac_lomac: if both flags are set on the new label, we
may not need to always fill out the label (only if one flag is
set, not both). Avoid stomping on a section of the label if we
are in fact modifying both elements.
Because we know that both flags will be set, we don't need to
test whether the range or single are set in later consistency
checks of the range and single -- just test them.
By checking the range of the new vs. the range of the old label
before testing the single against the new range, we implicitly
test that the new single is in the old range. Document this
with a comment.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
Framework labels:
- Re-work the label state assertions to use a set of central
ASSERT_type_LABEL() assertions.
- Test to make sure labels passed to externalize/internalize calls haven't
been destroyed.
- For access control checks, assert the condition of all labels passed in.
- For life cycle events, assert the condition of all labels passed in.
- Add new entry point implementations for new MAC Framework entry points:
mac_test_reflect_mbuf_icmp(), mac_test_reflect_mbuf_tcp(),
mac_test_check_vnode_deleteextattr(), mac_test_check_vnode_listextattr().
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
mac_stub policy and no longer mac_none (as found in the repocopy).
Add comment to this effect.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
explicit access control checks to delete and list extended attributes
on a vnode, rather than implicitly combining with the setextattr and
getextattr checks. This reflects EA API changes in the kernel made
recently, including the move to explicit VOP's for both of these
operations.
Obtained from: TrustedBSD PRoject
Sponsored by: DARPA, Network Associates Laboratories
MAC_DEBUG_COUNTER_INC() and MAC_DEBUG_COUNTER_DEC() to maintain
debugging counter values rather than #ifdef'ing the atomic
operations to MAC_DEBUG.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
mac_mls_subject_equal_ok() to mac_mls_subject_privileged(),
which more consistently reflects the fact that this is really
about our notion of privilege in the MLS policy.
Since we don't use suser() for privilege in MLS, remove
the suser check from the ifnet relabel ioctl, and replace it
with an MLS privilege check.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
already checks suser on a network interface relabel, so don't dup it
here. Rely solely on the Biba definition of privilege, which is
already tested.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
Submitted by: Andrew Reisse <areisse@nailabs.com>
the MAC policy modules to improve robustness against C string
bugs and vulnerabilities. Following these revisions, all
string construction of labels for export to userspace (or
elsewhere) is performed using the sbuf API, which prevents
the consumer from having to perform laborious and intricate
pointer and buffer checks. This substantially simplifies
the externalization logic, both at the MAC Framework level,
and in individual policies; this becomes especially useful
when policies export more complex label data, such as with
compartments in Biba and MLS.
Bundled in here are some other minor fixes associated with
externalization: including avoiding malloc while holding the
process mutex in mac_lomac, and hence avoid a failure mode
when printing labels during a downgrade operation due to
the removal of the M_NOWAIT case.
This has been running in the MAC development tree for about
three weeks without problems.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
policy definition structure; this permits policies to reduce their
number of gratuitous includes for required for entry points they
don't implement. This also facilitates building the MAC Framework
on Darwin.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
Several of the subtypes have an associated vnode which is used for
stuff like the f*() functions.
By giving the vnode a speparate field, a number of checks for the specific
subtype can be replaced simply with a check for f_vnode != NULL, and
we can later free f_data up to subtype specific use.
At this point in time, f_data still points to the vnode, so any code I
might have overlooked will still work.
mpo_copy_mbuf_label() entry point for Biba and MLS, respectively.
Otherwise, labels in m_tags may not be properly propagated across
some classes of mbuf operations. This problem caused these policies
to fail-stop the system with a panic.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
of C strings internally; C strings require a lot of return value
checking that (a) takes a lot of space, and (b) is difficult to get
right. Prior to the advent of compartment support, modeling APIs
for helper functions on snprintf worked fine; with the additional
complexity, the sbuf_printf() API makes a lot more sense.
While doing this, break out the printing of sequential compartment
lists into a helper function, mac_{biba,mls}_compartment_to_string().
This permits the main body of mac_{biba,mls}_element_to_string()
to be concerned only with identifying sequential ranges rather
than rendering.
At a less disruptive moment, we'll push the move from snprintf()-like
interface to sbuf()-like interface up into the MAC Framework layer.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
mismerged from the MAC tree, and didn't get picked up because warnings
are not normally fatal in per-module builds, only when they are linked
into a kernel (such as LINT).
Reported by: des and the technicolor tinderbox
Approved by: re (scottl)
