Commit Graph

138 Commits

Author SHA1 Message Date
rwatson
d575478d80 Update policy modules for changes in arguments associated with support
for label access on the interpreter, not just the shell script.  No
policies currently present in the system rely on the new labels.
2002-11-05 17:52:42 +00:00
rwatson
6c4f4d26f4 Bring in two sets of changes:
(1) Permit userland applications to request a change of label atomic
    with an execve() via mac_execve().  This is required for the
    SEBSD port of SELinux/FLASK.  Attempts to invoke this without
    MAC compiled in result in ENOSYS, as with all other MAC system
    calls.  Complexity, if desired, is present in policy modules,
    rather than the framework.

(2) Permit policies to have access to both the label of the vnode
    being executed as well as the interpreter if it's a shell
    script or related UNIX nonsense.  Because we can't hold both
    vnode locks at the same time, cache the interpreter label.
    SEBSD relies on this because it supports secure transitioning
    via shell script executables.  Other policies might want to
    take both labels into account during an integrity or
    confidentiality decision at execve()-time.

Approved by:	re
Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-11-05 17:51:56 +00:00
rwatson
4f3c382c18 Since neither the Biba policy nor the MLS policy make use of
transitioning, remove their transition entry points.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-11-05 16:44:29 +00:00
rwatson
373a915367 Assert that appropriate vnodes are locked in mac_execve_will_transition().
Allow transitioning to be twiddled off using the process and fs enforcement
flags, although at some point this should probably be its own flag.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-11-05 15:11:33 +00:00
rwatson
ca2d41f714 Implement mpo_check_system_acct and mpo_check_system_settime() for Biba:
require Biba privilege to configure either, and require that accounting
files be high integrity.  Note that this does allow implicit information
flow from low to high integrity, but it also protects the integrity
of accounting data.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-11-04 17:50:52 +00:00
rwatson
8ea7b65d85 Correct use of mac_biba_subject_privileged() in swapon() code.
Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-11-04 17:36:47 +00:00
rwatson
b8dd64f5ef Permit MAC policies to instrument the access control decisions for
system accounting configuration and for nfsd server thread attach.
Policies might use this to protect the integrity or confidentiality
of accounting data, limit the ability to turn on or off accounting,
as well as to prevent inappropriately labeled threads from becoming nfs
server threads.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-11-04 15:13:36 +00:00
rwatson
8f2b40ef3f Remove mac_cache_fslabel_in_vnode sysctl -- with the new VFS/MAC
construction, labels are always cached.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-11-04 14:55:14 +00:00
rwatson
c7ea6f5cb9 License and wording updates: NAI has authorized the removal of clause
three from their BSD-style license.  Also, s/NAI Labs/Network Associates
Laboratories/.
2002-11-04 01:53:12 +00:00
rwatson
89cdee7c52 License clarification and wording changes: NAI has approved removal of
clause three, and NAI Labs now goes by the name Network Associates
Laboratories.
2002-11-04 01:42:39 +00:00
rwatson
7537530ad8 Introduce mac_check_system_settime(), a MAC check allowing policies to
augment the system policy for changing the system time.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-11-03 02:39:42 +00:00
rwatson
02575bafa7 Change privilege model for mac_partition such that BSD superuser can change
the partition once a partition has been set.  This is required for correct
operation of sendmail between partitions.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-11-03 00:53:03 +00:00
mux
a79bd334d7 Fix some warnings on 64 bit architectures. The vn_extattr_get()
function takes an int * parameter, not a size_t * parameter.

Arguably, it should rather take a size_t *, but that would
require changing the uio_resid field of struct uio to be a size_t
instead of an int, which I don't want to do that close to
5.0-RELEASE.

Reviewed by:	rwatson
2002-11-02 20:16:35 +00:00
rwatson
61ffc1b9bb Add MAC checks for various kenv() operations: dump, get, set, unset,
permitting MAC policies to limit access to the kernel environment.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-11-01 20:46:53 +00:00
rwatson
122a6b9ad2 Move to C99 sparse structure initialization for the mac_policy_ops
structure definition, rather than using an operation vector
we translate into the structure.  Originally, we used a vector
for two reasons:

(1) We wanted to define the structure sparsely, which wasn't
    supported by the C compiler for structures.  For a policy
    with five entry points, you don't want to have to stick in
    a few hundred NULL function pointers.

(2) We thought it would improve ABI compatibility allowing modules
    to work with kernels that had a superset of the entry points
    defined in the module, even if the kernel had changed its
    entry point set.

Both of these no longer apply:

(1) C99 gives us a way to sparsely define a static structure.

(2) The ABI problems existed anyway, due to enumeration numbers,
    argument changes, and semantic mismatches.  Since the going
    rule for FreeBSD is that you really need your modules to
    pretty closely match your kernel, it's not worth the
    complexity.

This submit eliminates the operation vector, dynamic allocation
of the operation structure, copying of the vector to the
structure, and redoes the vectors in each policy to direct
structure definitions.  One enourmous benefit of this change
is that we now get decent type checking on policy entry point
implementation arguments.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-30 18:48:51 +00:00
rwatson
e3a98b382a Various minor type, prototype tweaks -- clean up cruft due to lack of
type checking on entry points (to be introduced shortly).

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-30 18:10:46 +00:00
rwatson
27e2336a32 While 'mode_t' seemed like a good idea for the access mode argument for
MAC access() and open() checks, the argument actually has an int type
where it becomes available.  Switch to using 'int' for the mode argument
throughout the MAC Framework and policy modules.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-30 17:56:57 +00:00
rwatson
d81ef804ab Try again to fix the KASSERT. 2002-10-30 00:16:59 +00:00
rwatson
fc851fde9e Fix a KASSERT bug that showed up only in the LINT build, not the
module build, so I missed it in the merge.

Pointed out by:	sam
2002-10-30 00:04:31 +00:00
rwatson
4db30046bd Hook up no-op stubs for reboot, swapon, sysctl entry points.
Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-29 19:57:28 +00:00
rwatson
6c3898d0fc Implement Biba policy entry points for mac_check_system_swapon()
and mac_check_system_sysctl(), providing additional integrity
protections relating to swap target device selection and system
management via sysctl().  Require Biba privilege for both; also
require that the target of swap operations be a high integrity
object, since swap data is high integrity.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Asssociates Laboratories
2002-10-29 19:18:52 +00:00
rwatson
34c75e428f Require Biba privilege to relabel a network interface.
Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-29 19:14:16 +00:00
rwatson
345064545a Correct a typo in a previously commented include entry that was made
visible in the recent commit.
2002-10-28 19:50:06 +00:00
rwatson
71ce8bbc83 Remove all reference to 'struct oldmac', since it's no longer required
with the new VFS/EA semantics in the MAC framework.  Move the per-policy
structures out to per-policy include files, removing all policy-specific
defines and structures out of the base framework includes and
implementation, making mac_biba and mac_mls entirely self-contained.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-28 19:44:05 +00:00
rwatson
9146f5fdfa Add a return type for mac_biba_high_single(), apparently lost in an
earlier merge.  It's a 'static int'.
2002-10-28 19:18:29 +00:00
rwatson
9c894a8e1c Rename mac_biba_subject_equal_ok() to mac_biba_subject_privileged()
to evolve the notion of Biba privilege a bit.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-28 19:17:39 +00:00
rwatson
1295b8ff0f Zero the trusted_interface buffer before starting parsing.
Print a warning if a requested interface name is longer than
IFNAMSIZ.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-28 19:16:44 +00:00
rwatson
9ae04d1a06 An inappropriate ASSERT slipped in during the recent merge of the
reboot checking; remove.
2002-10-28 18:53:53 +00:00
rwatson
e6f3037210 Centrally manage enforcement of {reboot,swapon,sysctl} using the
mac_enforce_system toggle, rather than several separate toggles.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-27 15:50:49 +00:00
rwatson
653f637c44 Implement mac_check_system_sysctl(), a MAC Framework entry point to
permit MAC policies to augment the security protections on sysctl()
operations.  This is not really a wonderful entry point, as we
only have access to the MIB of the target sysctl entry, rather than
the more useful entry name, but this is sufficient for policies
like Biba that wish to use their notions of privilege or integrity
to prevent inappropriate sysctl modification.  Affects MAC kernels
only.  Since SYSCTL_LOCK isn't in sysctl.h, just kern_sysctl.c,
we can't assert the SYSCTL subsystem lockin the MAC Framework.

Approved by:	re
Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-27 07:12:34 +00:00
rwatson
be98961ae9 Hook up mac_check_system_reboot(), a MAC Framework entry point that
permits MAC modules to augment system security decisions regarding
the reboot() system call, if MAC is compiled into the kernel.

Approved by:	re
Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-27 07:03:29 +00:00
rwatson
8cd9e63819 Merge from MAC tree: rename mac_check_vnode_swapon() to
mac_check_system_swapon(), to reflect the fact that the primary
object of this change is the running kernel as a whole, rather
than just the vnode.  We'll drop additional checks of this
class into the same check namespace, including reboot(),
sysctl(), et al.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-27 06:54:06 +00:00
rwatson
312cab0dee Slightly change the semantics of vnode labels for MAC: rather than
"refreshing" the label on the vnode before use, just get the label
right from inception.  For single-label file systems, set the label
in the generic VFS getnewvnode() code; for multi-label file systems,
leave the labeling up to the file system.  With UFS1/2, this means
reading the extended attribute during vfs_vget() as the inode is
pulled off disk, rather than hitting the extended attributes
frequently during operations later, improving performance.  This
also corrects sematics for shared vnode locks, which were not
previously present in the system.  This chances the cache
coherrency properties WRT out-of-band access to label data, but in
an acceptable form.  With UFS1, there is a small race condition
during automatic extended attribute start -- this is not present
with UFS2, and occurs because EAs aren't available at vnode
inception.  We'll introduce a work around for this shortly.

Approved by:	re
Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-26 14:38:24 +00:00
rwatson
068e73d389 Comment describing the semantics of mac_late.
Trim trailing whitespace.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-25 20:45:27 +00:00
rwatson
e8d6763a91 Provide a simple sample labeled access control policy, mac_partition.
This policy can be loaded dynamically, and assigns each process a
partition number, as well as permitting processes to operate outside
the partition.  Processes contained in a partition can only "see"
processes inside the same partition, so it's a little like jail.
The partition of a user can be set using the label mechanisms in
login.conf.  This sample policy is a good starting point for developers
wanting to learn about how to produce labeled policies, as it labels
only one kernel object, the process credential.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-23 23:36:27 +00:00
rwatson
29ef1b5025 Style fix: space between 'switch' and '('. 2002-10-22 19:01:49 +00:00
rwatson
d6241fec61 s/mls/biba/ in a copy+paste error for a printf. 2002-10-22 18:36:47 +00:00
rwatson
7b35ce62ba Remove the mac_te policy bits from 'struct oldmac' -- we're not going
to merge mac_te, since the SEBSD port of SELinux/FLASK provides a much
more mature Type Enforcement implementation.  This changes the size
of the on-disk 'struct oldmac' EA labels, which may require regeneration.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-22 17:19:06 +00:00
rwatson
3d192c6f03 Don't enforce MAC Biba policy for socket visibility if Biba is not
explicitly enabled.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-22 17:02:42 +00:00
rwatson
e40371a8f9 Introduce MAC_CHECK_VNODE_SWAPON, which permits MAC policies to
perform authorization checks during swapon() events; policies
might choose to enforce protections based on the credential
requesting the swap configuration, the target of the swap operation,
or other factors such as internal policy state.

Approved by:	re
Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-22 15:53:43 +00:00
rwatson
9fe777b3e6 Missed in previous merge: export sizeof(struct oldmac) rather than
sizeof(struct mac).

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-22 15:33:33 +00:00
rwatson
433e63644a Adapt MAC policies for the new user API changes; teach policies how
to parse their own label elements (some cleanup to occur here in the
future to use the newly added kernel strsep()).  Policies now
entirely encapsulate their notion of label in the policy module.

Approved by:	re
Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-22 14:31:34 +00:00
rwatson
4651fb3eba Support the new MAC user API in kernel: modify existing system calls
to use a modified notion of 'struct mac', and flesh out the new variation
system calls (almost identical to existing ones except that they permit
a pid to be specified for process label retrieval, and don't follow
symlinks).  This generalizes the label API so that the framework is
now almost entirely policy-agnostic.

Approved by:	re
Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-22 14:29:47 +00:00
rwatson
a60c645b42 Revised APIs for user process label management; the existing APIs relied
on all label parsing occuring in userland, and knowledge of the loaded
policies in the user libraries.  This revision of the API pushes that
parsing into the kernel, avoiding the need for shared library support
of policies in userland, permitting statically linked binaries (such
as ls, ps, and ifconfig) to use MAC labels.  In these API revisions,
high level parsing of the MAC label is done in the MAC Framework,
and interpretation of label elements is delegated to the MAC policy
modules.  This permits modules to export zero or more label elements
to user space if desired, and support them in the manner they want
and with the semantics they want.  This is believed to be the final
revision of this interface: from the perspective of user applications,
the API has actually not changed, although the ABI has.

Approved by:	re
Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-22 14:27:44 +00:00
rwatson
0a4c2cb09a mac_none is a stub policy without any functional implementation.
Various cleanups, no functional changes:

	- Fix a type in an entry point stub, socket checks accept
	  sockets, not vnodes.
	- Trailing whitespace
	- Entry point sort order

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-21 23:16:23 +00:00
rwatson
3304731f7b Introduce mac_biba_copy() and mac_mls_copy(), which conditionally
copy elements of one Biba or MLS label to another based on the flags
on the source label element.  Use this instead of
mac_{biba,mls}_{single,range}() to simplify the existing code, as
well as support partial label updates (we don't update if none is
requested).

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-21 20:55:39 +00:00
rwatson
63323cc3ae Add compartment support to Biba and MLS policies. The logic of the
policies remains the same: subjects and objects are labeled for
integrity or sensitivity, and a dominance operator determines whether
or not subject/object accesses are permitted to limit inappropriate
information flow.  Compartments are a non-hierarchal component to
the label, so add a bitfield to the label element for each, and a
set check as part of the dominance operator.  This permits the
implementation of "need to know" elements of MLS.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-21 18:42:01 +00:00
rwatson
a52c2344dd More in the way of minor consistency improvements: trim 'mac_mls_'
from another variable to line this up with mac_biba.c

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-21 18:14:30 +00:00
rwatson
a47467b826 Demote sockets to single-label objects rather than maintaining a
range on them, leaving process credentials as the only kernel
objects with label ranges in the Biba and MLS policies.  We
weren't using the range in any access control decisions, so this
lets us garbage collect effectively unused code.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-21 18:05:12 +00:00
rwatson
25b8d9a4ba Synchonize variable spelling with the MAC tree: we shortened some of
the names.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, Network Associates Laboratories
2002-10-21 17:05:48 +00:00