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)
constants in question refer to the number of label slots, not the
maximum number of policies that may be loaded. This should reduce
confusion regarding an element in the MAC sysctl MIB, as well as
make it more clear what the affect of changing the compile-time
constants is.
Approved by: re (jhb)
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
(1) Accept that we're now going to use mutexes, so don't attempt
to avoid treating them as mutexes. This cleans up locking
accessor function names some.
(2) Rename variables to _mtx, _cv, _count, simplifying the naming.
(3) Add a new form of the _busy() primitive that conditionally
makes the list busy: if there are entries on the list, bump
the busy count. If there are no entries, don't bump the busy
count. Return a boolean indicating whether or not the busy
count was bumped.
(4) Break mac_policy_list into two lists: one with the same name
holding dynamic policies, and a new list, mac_static_policy_list,
which holds policies loaded before mac_late and without the
unload flag set. The static list may be accessed without
holding the busy count, since it can't change at run-time.
(5) In general, prefer making the list busy conditionally, meaning
we pay only one mutex lock per entry point if all modules are
on the static list, rather than two (since we don't have to
lower the busy count when we're done with the framework). For
systems running just Biba or MLS, this will halve the mutex
accesses in the network stack, and may offer a substantial
performance benefits.
(6) Lay the groundwork for a dynamic-free kernel option which
eliminates all locking associated with dynamically loaded or
unloaded policies, for pre-configured systems requiring
maximum performance but less run-time flexibility.
These changes have been running for a few weeks on MAC development
branch systems.
Approved by: re (jhb)
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
- Add a parameter to vm_pageout_flush() that tells vm_pageout_flush()
whether its caller has locked the vm_object. (This is a temporary
measure to bootstrap vm_object locking.)
blocking allocation could occur as a result of a label
initialization. This will simulate the behavior of allocated
label policies such as MLS and Biba when running mac_test from
the perspective of WITNESS lock and sleep warnings.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
don't try and convert the argument flags to malloc flags, or we risk
implicitly requesting blocking and generating witness warnings.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
returning some additional room in the first mbuf in a chain, and
avoiding feature-specific contents in the mbuf header. To do this:
- Modify mbuf_to_label() to extract the tag, returning NULL if not
found.
- Introduce mac_init_mbuf_tag() which does most of the work
mac_init_mbuf() used to do, except on an m_tag rather than an
mbuf.
- Scale back mac_init_mbuf() to perform m_tag allocation and invoke
mac_init_mbuf_tag().
- Replace mac_destroy_mbuf() with mac_destroy_mbuf_tag(), since
m_tag's are now GC'd deep in the m_tag/mbuf code rather than
at a higher level when mbufs are directly free()'d.
- Add mac_copy_mbuf_tag() to support m_copy_pkthdr() and related
notions.
- Generally change all references to mbuf labels so that they use
mbuf_to_label() rather than &mbuf->m_pkthdr.label. This
required no changes in the MAC policies (yay!).
- Tweak mbuf release routines to not call mac_destroy_mbuf(),
tag destruction takes care of it for us now.
- Remove MAC magic from m_copy_pkthdr() and m_move_pkthdr() --
the existing m_tag support does all this for us. Note that
we can no longer just zero the m_tag list on the target mbuf,
rather, we have to delete the chain because m_tag's will
already be hung off freshly allocated mbuf's.
- Tweak m_tag copying routines so that if we're copying a MAC
m_tag, we don't do a binary copy, rather, we initialize the
new storage and do a deep copy of the label.
- Remove use of MAC_FLAG_INITIALIZED in a few bizarre places
having to do with mbuf header copies previously.
- When an mbuf is copied in ip_input(), we no longer need to
explicitly copy the label because it will get handled by the
m_tag code now.
- No longer any weird handling of MAC labels in if_loop.c during
header copies.
- Add MPC_LOADTIME_FLAG_LABELMBUFS flag to Biba, MLS, mac_test.
In mac_test, handle the label==NULL case, since it can be
dynamically loaded.
In order to improve performance with this change, introduce the notion
of "lazy MAC label allocation" -- only allocate m_tag storage for MAC
labels if we're running with a policy that uses MAC labels on mbufs.
Policies declare this intent by setting the MPC_LOADTIME_FLAG_LABELMBUFS
flag in their load-time flags field during declaration. Note: this
opens up the possibility of post-boot policy modules getting back NULL
slot entries even though they have policy invariants of non-NULL slot
entries, as the policy might have been loaded after the mbuf was
allocated, leaving the mbuf without label storage. Policies that cannot
handle this case must be declared as NOTLATE, or must be modified.
- mac_labelmbufs holds the current cumulative status as to whether
any policies require mbuf labeling or not. This is updated whenever
the active policy set changes by the function mac_policy_updateflags().
The function iterates the list and checks whether any have the
flag set. Write access to this variable is protected by the policy
list; read access is currently not protected for performance reasons.
This might change if it causes problems.
- Add MAC_POLICY_LIST_ASSERT_EXCLUSIVE() to permit the flags update
function to assert appropriate locks.
- This makes allocation in mac_init_mbuf() conditional on the flag.
Reviewed by: sam
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
mbuf_to_label(). This permits the vast majority of entry point code
to be unaware that labels are stored in m->m_pkthdr.label, such that
we can experiment storage of labels elsewhere (such as in m_tags).
Reviewed by: sam
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
of asserting that an mbuf has a packet header. Use it instead of hand-
rolled versions wherever applicable.
Submitted by: Hiten Pandya <hiten@unixdaemons.com>
the vendor is only included in the long name currently, reducing
verbosity when modules are registered and unregistered.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
additional flags argument to indicate blocking disposition, and
pass in M_NOWAIT from the IP reassembly code to indicate that
blocking is not OK when labeling a new IP fragment reassembly
queue. This should eliminate some of the WITNESS warnings that
have started popping up since fine-grained IP stack locking
started going in; if memory allocation fails, the creation of
the fragment queue will be aborted.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
functionality for the following entry pints:
mac_test_init_proc_label()
mac_test_destroy_proc_label()
For process labeling entry points, now also track the use of process
labels and test assertions about their integrity and life cycle.
mac_test_thread_userret()
mac_test_check_kenv_dump()
mac_test_check_kenv_get()
mac_test_check_kenv_set()
mac_test_check_kenv_unset()
mac_test_check_kld_load()
mac_test_check_kld_stat()
mac_test_check_kld_unload()
mac_test_check_sysarch_ioperm()
mac_test_check_system_acct()
mac_test_check_system_reboot()
mac_test_check_system_settime()
mac_test_check_system_swapon()
mac_test_check_system_swapoff()
mac_test_check_system_sysctl()
For other entry points, just provide testing stubs.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
for enforcement:
mac_mls_check_system_swapon() - Require that the subject and the
swapfile target vnode labels dominate one another. An additional
check is probably needed here to require that the swapfile target
has a label of mls/high to prevent information leakage through
swapfiles.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
include a new entry point available for enforcement:
mac_bsdextended_check_system_swapon() - Apply extended access
control checks to the file target of swap.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
points available for enforcement:
mac_biba_check_sysarch_ioperm() - Require Biba privilege to make
use of privileged machine-dependent interfaces, protecting against
bypass of the policy via various mechanisms.
mac_biba_check_system_swapoff() - Require Biba privilege to disable
swapping against a vnode target.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
which are no longer required now that we have UFS2 with extended
attribute transactions.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
check, mac_check_sysarch_ioperm(), permitting MAC security policy
modules to control access to these interfaces. Currently, they
protect access to IOPL on i386, and setting HAE on Alpha.
Additional checks might be required on other platforms to prevent
bypass of kernel security protections by unauthorized processes.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
modules to authorize disabling of swap against a particular vnode.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
permit users and groups to bind ports for TCP or UDP, and is intended
to be combined with the recently committed support for
net.inet.ip.portrange.reservedhigh. The policy is twiddled using
sysctl(8). To use this module, you will need to compile in MAC
support, and probably set reservedhigh to 0, then twiddle
security.mac.portacl.rules to set things as desired. This policy
module only restricts ports explicitly bound using bind(), not
implicitly bound ports where the port number is selected by the
IP stack. It appears to work properly in my local configuration,
but needs more broad testing.
A sample policy might be:
# sysctl security.mac.portacl.rules="uid:425:tcp:80,uid:425:tcp:79"
This permits uid 425 to bind TCP sockets to ports 79 and 80. Currently
no distinction is made for incoming vs. outgoing ports with TCP,
although that would probably be easy to add.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
I was in two minds as to where to put them in the first case..
I should have listenned to the other mind.
Submitted by: parts by davidxu@
Reviewed by: jeff@ mini@
MAC policy. To load a KLD, require that the subject hold Biba privilege,
and the the kernel module be marked as high integrity. To unload a
KLD, require that the subject hold Biba privilege.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
and MLS policies: as we support both an effective (single) element and
range (available) elements, require that the single be in the range if
both the single and range are defined in the update. Remove comments
suggesting that such a check might be a good idea.
Don't introduce a similar check for network interfaces; due to different
interpretations of the single and range elements, it's not clear that
it's useful to do so.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
labeling for Biba.
Rename the variable 'level' to 'type' in interface parsing and
labeling for MLS.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
pointer types, and remove a huge number of casts from code using it.
Change struct xfile xf_data to xun_data (ABI is still compatible).
If we need to add a #define for f_data and xf_data we can, but I don't
think it will be necessary. There are no operational changes in this
commit.
kernel, you should expect them to do something, so now they do. This
doesn't affect users who don't load or explicitly compile in the
policies.
Approved by: re (jhb)
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
unused. Replace it with a dm_mount back-pointer to the struct mount
that the devfs_mount is associated with. Export that pointer to MAC
Framework entry points, where all current policies don't use the
pointer. This permits the SEBSD port of SELinux's FLASK/TE to compile
out-of-the-box on 5.0-CURRENT with full file system labeling support.
Approved by: re (murray)
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
wrong, since we don't want the variable changed, but since we assign
it to variables that may also refer to other non-const strings,
warnings were generated that could break LINT.
Approved by: re
Spotted by: sam
Control) as a MAC Framework policy module. Unlike the existing
src/sys/security/lomac implementation, this one has its fingers out
of the kernel lock order and doesn't make use of flags in existing
kernel structures. This greatly reduces the quantity of replicated
code with src/sys/kern, simplifies the implementation (3000 vs 8500
lines), and correctes a number of known stability problems with
the existing LOMAC implementation, which will be removed. A bit
more hooking up to do here.
Approved by: re
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
by policy modules making use of downgrades in the MAC AST event. This
is required by the mac_lomac port of LOMAC to the MAC Framework.
Approved by: re
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
in struct proc. While the process label is actually stored in the
struct ucred pointed to by p_ucred, there is a need for transient
storage that may be used when asynchronous (deferred) updates need to
be performed on the "real" label for locking reasons. Unlike other
label storage, this label has no locking semantics, relying on policies
to provide their own protection for the label contents, meaning that
a policy leaf mutex may be used, avoiding lock order issues. This
permits policies that act based on historical process behavior (such
as audit policies, the MAC Framework port of LOMAC, etc) can update
process properties even when many existing locks are held without
violating the lock order. No currently committed policies implement use
of this label storage.
Approved by: re
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
checks permit policy modules to augment the system policy for permitting
kld operations. This permits policies to limit access to kld operations
based on credential (and other) properties, as well as to perform checks
on the kld being loaded (integrity, etc).
Approved by: re
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
the MAC policy list is busy during a load or unload attempt.
We assert no locks held during the cv wait, meaning we should
be fairly deadlock-safe. Because of the cv model and busy
count, it's possible for a cv waiter waiting for exclusive
access to the policy list to be starved by active and
long-lived access control/labeling events. For now, we
accept that as a necessary tradeoff.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
we brought in the new cache and locking model for vnode labels. We
now rely on mac_associate_devfs_vnode().
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
dynamic mapping of an operation vector into an operation structure,
rather, we rely on C99 sparse structure initialization.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
points, rather than relying on policies to grub around in the
image activator instance structure.
Approved by: re
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
(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
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
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
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
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
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
permitting MAC policies to limit access to the kernel environment.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
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
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
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
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
Print a warning if a requested interface name is longer than
IFNAMSIZ.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
mac_enforce_system toggle, rather than several separate toggles.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
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
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
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
"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
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
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
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
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
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
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
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
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
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
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
collapse the two cases more cleanly: rather than wrapping an access
check around open, simply provide the open implementation for the
access vector entry. No functional change.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
we just break out some of the tests better. Minor change in that
we now better support incremental update of labels.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
instead of the default biba/high, mls/low, making it easier to use
ptys with these policies. This isn't the final solution, but does
help.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
compile fail. MAC_MAX_POLICIES should always be defined, or we have
bigger problems at hand.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
unregister. Under some obscure (perhaps demented) circumstances,
this can result in a panic if a policy is unregistered, and then someone
foolishly unregisters it again.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
that use it. Specifically, vop_stdlock uses the lock pointed to by
vp->v_vnlock. By default, getnewvnode sets up vp->v_vnlock to
reference vp->v_lock. Filesystems that wish to use the default
do not need to allocate a lock at the front of their node structure
(as some still did) or do a lockinit. They can simply start using
vn_lock/VOP_UNLOCK. Filesystems that wish to manage their own locks,
but still use the vop_stdlock functions (such as nullfs) can simply
replace vp->v_vnlock with a pointer to the lock that they wish to
have used for the vnode. Such filesystems are responsible for
setting the vp->v_vnlock back to the default in their vop_reclaim
routine (e.g., vp->v_vnlock = &vp->v_lock).
In theory, this set of changes cleans up the existing filesystem
lock interface and should have no function change to the existing
locking scheme.
Sponsored by: DARPA & NAI Labs.
checks from the MAC tree: allow policies to perform access control
for the ability of a process to send and receive data via a socket.
At some point, we might also pass in additional address information
if an explicit address is requested on send.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
seperate entry points for each occasion:
mac_check_vnode_mmap() Check at initial mapping
mac_check_vnode_mprotect() Check at mapping protection change
mac_check_vnode_mmap_downgrade() Determine if a mapping downgrade
should take place following
subject relabel.
Implement mmap() and mprotect() entry points for labeled vnode
policies. These entry points are currently not hooked up to the
VM system in the base tree. These changes improve the consistency
of the access control interface and offer more flexibility regarding
limiting access to vnode mmaping.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
flags so that we can call malloc with M_NOWAIT if necessary, avoiding
potential sleeps while holding mutexes in the TCP syncache code.
Similar to the existing support for mbuf label allocation: if we can't
allocate all the necessary label store in each policy, we back out
the label allocation and fail the socket creation. Sync from MAC tree.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
devfs VOP symlink creation by introducing a new entry point to determine
the label of the devfs_dirent prior to allocation of a vnode for the
symlink.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
point that instruments the creation of hard links. Policy implementations
to follow.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
to mbuf label initialization, that functionality was never merged to
the main tree. Go ahead and merge that functionality now. Note that
this requires policy modules to accept the case where the label
element may be destroyed even if init has not succeeded on it (in
the event that policy failed the init). This will shortly also
apply to sockets.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
order used in mac_policy.h and elsewhere. Sort order is basically
"by operation category", then "alphabetically by object". Sync to
MAC tree.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
externalization, and cred label life cycle events to entirely above
devfs and vnode events. Sync from MAC tree.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
entry points to better match the entry point ordering in mac_policy.h.
Big diff, no functional change; merge from the MAC tree.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
- If a policy isn't registered when a policy module unloads, silently
succeed.
- Hold the policy list lock across more of the validity tests to avoid
races.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
- Change mpo_init_foo(obj, label) and mpo_destroy_foo(obj, label) policy
entry points to mpo_init_foo_label(label) and
mpo_destroy_foo_label(label). This will permit the use of the same
entry points for holding temporary type-specific label during
internalization and externalization, as well as for caching purposes.
- Because of this, break out mpo_{init,destroy}_socket() and
mpo_{init,destroy}_mount() into seperate entry points for socket
main/peer labels and mount main/fs labels.
- Since the prototype for label initialization is the same across almost
all entry points, implement these entry points using common
implementations for Biba, MLS, and Test, reducing the number of
almost identical looking functions.
This simplifies policy implementation, as well as preparing us for the
merge of the new flexible userland API for managing labels on objects.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
modules to perform MAC-related events when a thread returns to user
space. This is required for policies that have floating process labels,
as it's not always possible to acquire the process lock at arbitrary
points in the stack during system call processing; process labels might
represent traditional authentication data, process history information,
or other data.
LOMAC will use this entry point to perform the process label update
prior to the thread returning to userspace, when plugged into the MAC
framework.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
(1) Where previously the pipe mutex was selectively grabbed during
pipe_ioctl(), now always grab it and then release if if not
needed. This protects the call to mac_check_pipe_ioctl() to
make sure the label remains consistent. (Note: it looks
like sigio locking may be incorrect for fgetown() since we
call it not-by-reference and sigio locking assumes call by
reference).
(2) In pipe_stat(), lock the pipe if MAC is compiled in so that
the call to mac_check_pipe_stat() gets a locked pipe to
protect label consistency. We still release the lock before
returning actual stat() data, risking inconsistency, but
apparently our pipe locking model accepts that risk.
(3) In various pipe MAC authorization checks, assert that the pipe
lock is held.
(4) Grab the lock when performing a pipe relabel operation, and
assert it a little deeper in the stack.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
TrustedBSD MAC Perforce tree. Remove unused functions
mac_biba_equal_range and mac_mls_equal_range, which determined if the
ranges in two range-enabled labels were equal.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
use the notion that a subject range of (low-high) connotes Biba
privilege rather than a single of high.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
module and is not linked into the base system, two KASSERT's rotted.
Fix them by fixing variable names. It would be really nice if
opt_global.h was used when building modules as part of a buildkernel.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
v_tag is now const char * and should only be used for debugging.
Additionally:
1. All users of VT_NTS now check vfsconf->vf_type VFCF_NETWORK
2. The user of VT_PROCFS now checks for the new flag VV_PROCDEP, which
is propagated by pseudofs to all child vnodes if the fs sets PFS_PROCDEP.
Suggested by: phk
Reviewed by: bde, rwatson (earlier version)
layers deep in <sys/proc.h> or <sys/vnode.h>.
Removed unused includes.
Fixed some printf format errors (1 fatal on i386's; 1 fatal on alphas;
1 not fatal on any supported machine).
proc locking when revoking access to mmaps. Instead, perform this
later once we've changed the process label (hold onto a reference
to the new cred so that we don't lose it when we release the
process lock if another thread changes the credential).
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
for mac_check_vnode_{poll,read,stat,write}(). Pass in fp->f_cred
when calling these checks with a struct file available. Otherwise,
pass NOCRED. All currently MAC policies use active_cred, but
could now offer the cached credential semantic used for the base
system security model.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
can offer new services without reserving system call numbers, or
augmented versions of existing services. User code requests a
target policy by name, and specifies the policy-specific API plus
target. This is required in particular for our port of SELinux/FLASK
to the MAC framework since it offers additional security services.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
mac_check_pipe_poll(), mac_check_pipe_read(), mac_check_pipe_stat(),
and mac_check_pipe_write(). This is improves consistency with other
access control entry points and permits security modules to only
control the object methods that they are interested in, avoiding
switch statements.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
mac_check_vnode_poll(), mac_check_vnode_read(), mac_check_vnode_write().
This improves the consistency with other existing vnode checks, and
allows policies to avoid implementing switch statements to determine
what operations they do and do not want to authorize.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
we can check and use it later on.
Change the pieces of code which relied on mount->mnt_stat.f_owner
to check which user mounted the filesystem.
This became needed as the EA code needs to be able to allocate
blocks for "system" EA users like ACLs.
There seems to be some half-baked (probably only quarter- actually)
notion that the superuser for a given filesystem is the user who
mounted it, but this has far from been carried through. It is
unclear if it should be.
Sponsored by: DARPA & NAI Labs.
can avoid the cost of a large number of atomic operations if we're not
interested in the object count statistics.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
we can use the names _receive() and _send() for the receive() and send()
checks. Rename related constants, policy implementations, etc.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
we can use the names _receive() and _send() for the receive() and send()
checks. Rename related constants, policy implementations, etc.
PR:
Submitted by:
Reviewed by:
Approved by:
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
MFC after:
during a label change resulting in an mmap removal. This is "fail stop"
behavior, which is preferred, although it offers slightly less
transparency.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
us to reduce namespace pollution by doing a nested include of _label.h
rather than mac.h. mac.h contains lots of baggage, whereas _label.h
contains much less. A follow-up sweep to change nested inclusion will
follow. The problem regarding exporting 'struct label' to userland
due to excessive exporting of kernel structures to userland still
needs to be resolved.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
Suggested by: bde
enabled and the kernel provides the MAC registration and entry point
service. Declare a dependency on that module service for any
MAC module registered using mac_policy.h. For now, hard code the
version as 1, but once we've come up with a versioning policy, we'll
move to a #define of some sort. In the mean time, this will prevent
loading a MAC module when 'options MAC' isn't present, which (due to
a bug in the kernel linker) can result if the MAC module is preloaded
via loader.conf.
This particular evil recommended by: peter
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI LAbs
- v_vflag is protected by the vnode lock and is used when synchronization
with VOP calls is needed.
- v_iflag is protected by interlock and is used for dealing with vnode
management issues. These flags include X/O LOCK, FREE, DOOMED, etc.
- All accesses to v_iflag and v_vflag have either been locked or marked with
mp_fixme's.
- Many ASSERT_VOP_LOCKED calls have been added where the locking was not
clear.
- Many functions in vfs_subr.c were restructured to provide for stronger
locking.
Idea stolen from: BSD/OS
structure. This prevents a boatload of warnings in the MAC modules,
so we can hook them up to the build.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
kernel access control.
Provide implementations of some sample operating system security
policy extensions. These are not yet hooked up to the build as
other infrastructure is still being committed. Most of these
work fairly well and are in daily use in our development and (limited)
production environments. Some are not yet in their final form,
and a number of the labeled policies waste a lot of kernel memory
and will be fixed over the next month or so to be more conservative.
They do give good examples of the flexibility of the MAC framework
for implementing a variety of security policies.
mac_biba: Implementation of fixed-label Biba integrity policy,
similar to those found in a number of commercial
trusted operating systems. All subjects and objects
are assigned integrity levels, and information flow
is controlled based on a read-up, write-down
policy. Currently, purely hierarchal.
mac_bsdextended: Implementation of a "file system firewall",
which allows the administrator to specify a series
of rules limiting access by users and groups to
objects owned by other users and groups. This
policy is unlabeled, relying on existing system
security labeling (file permissions/ownership,
process credentials).
mac_ifoff: Secure interface silencing. Special-purpose module
to limit inappropriate out-going network traffic
for silent monitoring scenarios. Prevents the
various network stacks from generating any output
despite an interface being live for reception.
mac_mls: Implementation of fixed-label Multi-Level Security
confidentiality policy, similar to those found in
a number of commercial trusted operating systems.
All subjects and objects are assigned confidentiality
levels, and information flow is controlled based on
a write-up, read-down policy. Currently, purely
hiearchal, although non-hierarchal support is in the
works.
mac_none: Policy module implementing all MAC policy entry
points with empty stubs. A good place to start if
you want all the prototypes types in for you, and
don't mind a bit of pruning. Can be loaded, but
has no access control impact. Useful also for
performance measurements.
mac_seeotheruids: Policy module implementing a security service
similar to security.bsd.seeotheruids, only a slightly
more detailed policy involving exceptions for members
of specific groups, etc. This policy is unlabeled,
relying on existing system security labeling
(process credentials).
mac_test: Policy module implementing basic sanity tests for
label handling. Attempts to ensure that labels are
not freed multiple times, etc, etc.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
the number of policy slots to 4.
(Having run a quick errand, time to start on phase 2 of the MAC
integration)
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
kernel access control. The MAC framework permits loadable kernel
modules to link to the kernel at compile-time, boot-time, or run-time,
and augment the system security policy. This commit includes the
initial kernel implementation, although the interface with the userland
components of the oeprating system is still under work, and not all
kernel subsystems are supported. Later in this commit sequence,
documentation of which kernel subsystems will not work correctly with
a kernel compiled with MAC support will be added.
kern_mac.c contains the body of the MAC framework. Kernel and
user APIs defined in mac.h are implemented here, providing a front end
to loaded security modules. This code implements a module registration
service, state (label) management, security configuration and policy
composition.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
kernel access control. The MAC framework permits loadable kernel
modules to link to the kernel at compile-time, boot-time, or run-time,
and augment the system security policy. This commit includes the
initial kernel implementation, although the interface with the userland
components of the oeprating system is still under work, and not all
kernel subsystems are supported. Later in this commit sequence,
documentation of which kernel subsystems will not work correctly with
a kernel compiled with MAC support will be added.
Include files to declare MAC userland interface (mac.h), MAC subsystem
entry points (mac.h), and MAC policy entry points (mac_policy.h). These
files define the interface between the kernel and the MAC framework,
and between the MAC framework and each registered policy module. These
APIs and ABIs may not be assumed to be stable until following FreeBSD
5.1-RELEASE.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
o Add a mutex (sb_mtx) to struct sockbuf. This protects the data in a
socket buffer. The mutex in the receive buffer also protects the data
in struct socket.
o Determine the lock strategy for each members in struct socket.
o Lock down the following members:
- so_count
- so_options
- so_linger
- so_state
o Remove *_locked() socket APIs. Make the following socket APIs
touching the members above now require a locked socket:
- sodisconnect()
- soisconnected()
- soisconnecting()
- soisdisconnected()
- soisdisconnecting()
- sofree()
- soref()
- sorele()
- sorwakeup()
- sotryfree()
- sowakeup()
- sowwakeup()
Reviewed by: alfred
pointer instead of a proc pointer and require the process pointed to
by the second argument to be locked. We now use the thread ucred reference
for the credential checks in p_can*() as a result. p_canfoo() should now
no longer need Giant.
general cleanup of the API. The entire API now consists of two functions
similar to the pre-KSE API. The suser() function takes a thread pointer
as its only argument. The td_ucred member of this thread must be valid
so the only valid thread pointers are curthread and a few kernel threads
such as thread0. The suser_cred() function takes a pointer to a struct
ucred as its first argument and an integer flag as its second argument.
The flag is currently only used for the PRISON_ROOT flag.
Discussed on: smp@
spares (the size of the field was changed from u_short to u_int to
reflect what it really ends up being). Accordingly, change users of
xucred to set and check this field as appropriate. In the kernel,
this is being done inside the new cru2x() routine which takes a
`struct ucred' and fills out a `struct xucred' according to the
former. This also has the pleasant sideaffect of removing some
duplicate code.
Reviewed by: rwatson
o Modify the system call syntax for extattr_{get,set}_{fd,file}() so
as not to use the scatter gather API (which appeared not to be used
by any consumers, and be less portable), rather, accepts 'data'
and 'nbytes' in the style of other simple read/write interfaces.
This changes the API and ABI.
o Modify system call semantics so that extattr_get_{fd,file}() return
a size_t. When performing a read, the number of bytes read will
be returned, unless the data pointer is NULL, in which case the
number of bytes of data are returned. This changes the API only.
o Modify the VOP_GETEXTATTR() vnode operation to accept a *size_t
argument so as to return the size, if desirable. If set to NULL,
the size will not be returned.
o Update various filesystems (pseodofs, ufs) to DTRT.
These changes should make extended attributes more useful and more
portable. More commits to rebuild the system call files, as well
as update userland utilities to follow.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
this is a low-functionality change that changes the kernel to access the main
thread of a process via the linked list of threads rather than
assuming that it is embedded in the process. It IS still embeded there
but remove all teh code that assumes that in preparation for the next commit
which will actually move it out.
Reviewed by: peter@freebsd.org, gallatin@cs.duke.edu, benno rice,
