The counters are exported by a sysctl and have the same width on all
platforms anyway.
Reviewed by: cem, delphij, jhb
Sponsored by: Rubicon Communications, LLC (Netgate)
Differential Revision: https://reviews.freebsd.org/D25465
This permits requests to provide the AAD in a separate side buffer
instead of as a region in the crypto request input buffer. This is
useful when the main data buffer might not contain the full AAD
(e.g. for TLS or IPsec with ESN).
Unlike separate IVs which are constrained in size and stored in an
array in struct cryptop, separate AAD is provided by the caller
setting a new crp_aad pointer to the buffer. The caller must ensure
the pointer remains valid and the buffer contents static until the
request is completed (e.g. when the callback routine is invoked).
As with separate output buffers, not all drivers support this feature.
Consumers must request use of this feature via a new session flag.
To aid in driver testing, kern.crypto.cryptodev_separate_aad can be
set to force /dev/crypto requests to use a separate AAD buffer.
Discussed with: cem
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D25288
This is a testing aid to permit using testing a driver's support of
separate output buffers via cryptocheck.
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D24545
Some crypto consumers such as GELI and KTLS for file-backed sendfile
need to store their output in a separate buffer from the input.
Currently these consumers copy the contents of the input buffer into
the output buffer and queue an in-place crypto operation on the output
buffer. Using a separate output buffer avoids this copy.
- Create a new 'struct crypto_buffer' describing a crypto buffer
containing a type and type-specific fields. crp_ilen is gone,
instead buffers that use a flat kernel buffer have a cb_buf_len
field for their length. The length of other buffer types is
inferred from the backing store (e.g. uio_resid for a uio).
Requests now have two such structures: crp_buf for the input buffer,
and crp_obuf for the output buffer.
- Consumers now use helper functions (crypto_use_*,
e.g. crypto_use_mbuf()) to configure the input buffer. If an output
buffer is not configured, the request still modifies the input
buffer in-place. A consumer uses a second set of helper functions
(crypto_use_output_*) to configure an output buffer.
- Consumers must request support for separate output buffers when
creating a crypto session via the CSP_F_SEPARATE_OUTPUT flag and are
only permitted to queue a request with a separate output buffer on
sessions with this flag set. Existing drivers already reject
sessions with unknown flags, so this permits drivers to be modified
to support this extension without requiring all drivers to change.
- Several data-related functions now have matching versions that
operate on an explicit buffer (e.g. crypto_apply_buf,
crypto_contiguous_subsegment_buf, bus_dma_load_crp_buf).
- Most of the existing data-related functions operate on the input
buffer. However crypto_copyback always writes to the output buffer
if a request uses a separate output buffer.
- For the regions in input/output buffers, the following conventions
are followed:
- AAD and IV are always present in input only and their
fields are offsets into the input buffer.
- payload is always present in both buffers. If a request uses a
separate output buffer, it must set a new crp_payload_start_output
field to the offset of the payload in the output buffer.
- digest is in the input buffer for verify operations, and in the
output buffer for compute operations. crp_digest_start is relative
to the appropriate buffer.
- Add a crypto buffer cursor abstraction. This is a more general form
of some bits in the cryptosoft driver that tried to always use uio's.
However, compared to the original code, this avoids rewalking the uio
iovec array for requests with multiple vectors. It also avoids
allocate an iovec array for mbufs and populating it by instead walking
the mbuf chain directly.
- Update the cryptosoft(4) driver to support separate output buffers
making use of the cursor abstraction.
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D24545
The opencrypto ioctl code has very useful probe points at the various exit
points. These allow us to figure out exactly why a request failed. However, a
few paths did not have these probe points. Add them here.
Reviewed by: jhb
Although a few drivers supported this algorithm, there were never any
in-kernel consumers. cryptosoft and cryptodev never supported it,
and there was not a software xform auth_hash for it.
Reviewed by: cem
Relnotes: yes
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D24767
This removes support for the following algorithms:
- ARC4
- Blowfish
- CAST128
- DES
- 3DES
- MD5-HMAC
- Skipjack
Since /dev/crypto no longer supports 3DES, stop testing the 3DES KAT
vectors in cryptotest.py.
Reviewed by: cem (previous version)
Relnotes: yes
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D24346
Coverity noted that cod pointer is always non-NULL at the end of
cryptodev_aead(). While here, fix cryptodev_op() to match by making
one earlier failure case before cod and crp are allocated just return
directly.
CID: 1422185
Reported by: Coverity
- The linked list of cryptoini structures used in session
initialization is replaced with a new flat structure: struct
crypto_session_params. This session includes a new mode to define
how the other fields should be interpreted. Available modes
include:
- COMPRESS (for compression/decompression)
- CIPHER (for simply encryption/decryption)
- DIGEST (computing and verifying digests)
- AEAD (combined auth and encryption such as AES-GCM and AES-CCM)
- ETA (combined auth and encryption using encrypt-then-authenticate)
Additional modes could be added in the future (e.g. if we wanted to
support TLS MtE for AES-CBC in the kernel we could add a new mode
for that. TLS modes might also affect how AAD is interpreted, etc.)
The flat structure also includes the key lengths and algorithms as
before. However, code doesn't have to walk the linked list and
switch on the algorithm to determine which key is the auth key vs
encryption key. The 'csp_auth_*' fields are always used for auth
keys and settings and 'csp_cipher_*' for cipher. (Compression
algorithms are stored in csp_cipher_alg.)
- Drivers no longer register a list of supported algorithms. This
doesn't quite work when you factor in modes (e.g. a driver might
support both AES-CBC and SHA2-256-HMAC separately but not combined
for ETA). Instead, a new 'crypto_probesession' method has been
added to the kobj interface for symmteric crypto drivers. This
method returns a negative value on success (similar to how
device_probe works) and the crypto framework uses this value to pick
the "best" driver. There are three constants for hardware
(e.g. ccr), accelerated software (e.g. aesni), and plain software
(cryptosoft) that give preference in that order. One effect of this
is that if you request only hardware when creating a new session,
you will no longer get a session using accelerated software.
Another effect is that the default setting to disallow software
crypto via /dev/crypto now disables accelerated software.
Once a driver is chosen, 'crypto_newsession' is invoked as before.
- Crypto operations are now solely described by the flat 'cryptop'
structure. The linked list of descriptors has been removed.
A separate enum has been added to describe the type of data buffer
in use instead of using CRYPTO_F_* flags to make it easier to add
more types in the future if needed (e.g. wired userspace buffers for
zero-copy). It will also make it easier to re-introduce separate
input and output buffers (in-kernel TLS would benefit from this).
Try to make the flags related to IV handling less insane:
- CRYPTO_F_IV_SEPARATE means that the IV is stored in the 'crp_iv'
member of the operation structure. If this flag is not set, the
IV is stored in the data buffer at the 'crp_iv_start' offset.
- CRYPTO_F_IV_GENERATE means that a random IV should be generated
and stored into the data buffer. This cannot be used with
CRYPTO_F_IV_SEPARATE.
If a consumer wants to deal with explicit vs implicit IVs, etc. it
can always generate the IV however it needs and store partial IVs in
the buffer and the full IV/nonce in crp_iv and set
CRYPTO_F_IV_SEPARATE.
The layout of the buffer is now described via fields in cryptop.
crp_aad_start and crp_aad_length define the boundaries of any AAD.
Previously with GCM and CCM you defined an auth crd with this range,
but for ETA your auth crd had to span both the AAD and plaintext
(and they had to be adjacent).
crp_payload_start and crp_payload_length define the boundaries of
the plaintext/ciphertext. Modes that only do a single operation
(COMPRESS, CIPHER, DIGEST) should only use this region and leave the
AAD region empty.
If a digest is present (or should be generated), it's starting
location is marked by crp_digest_start.
Instead of using the CRD_F_ENCRYPT flag to determine the direction
of the operation, cryptop now includes an 'op' field defining the
operation to perform. For digests I've added a new VERIFY digest
mode which assumes a digest is present in the input and fails the
request with EBADMSG if it doesn't match the internally-computed
digest. GCM and CCM already assumed this, and the new AEAD mode
requires this for decryption. The new ETA mode now also requires
this for decryption, so IPsec and GELI no longer do their own
authentication verification. Simple DIGEST operations can also do
this, though there are no in-tree consumers.
To eventually support some refcounting to close races, the session
cookie is now passed to crypto_getop() and clients should no longer
set crp_sesssion directly.
- Assymteric crypto operation structures should be allocated via
crypto_getkreq() and freed via crypto_freekreq(). This permits the
crypto layer to track open asym requests and close races with a
driver trying to unregister while asym requests are in flight.
- crypto_copyback, crypto_copydata, crypto_apply, and
crypto_contiguous_subsegment now accept the 'crp' object as the
first parameter instead of individual members. This makes it easier
to deal with different buffer types in the future as well as
separate input and output buffers. It's also simpler for driver
writers to use.
- bus_dmamap_load_crp() loads a DMA mapping for a crypto buffer.
This understands the various types of buffers so that drivers that
use DMA do not have to be aware of different buffer types.
- Helper routines now exist to build an auth context for HMAC IPAD
and OPAD. This reduces some duplicated work among drivers.
- Key buffers are now treated as const throughout the framework and in
device drivers. However, session key buffers provided when a session
is created are expected to remain alive for the duration of the
session.
- GCM and CCM sessions now only specify a cipher algorithm and a cipher
key. The redundant auth information is not needed or used.
- For cryptosoft, split up the code a bit such that the 'process'
callback now invokes a function pointer in the session. This
function pointer is set based on the mode (in effect) though it
simplifies a few edge cases that would otherwise be in the switch in
'process'.
It does split up GCM vs CCM which I think is more readable even if there
is some duplication.
- I changed /dev/crypto to support GMAC requests using CRYPTO_AES_NIST_GMAC
as an auth algorithm and updated cryptocheck to work with it.
- Combined cipher and auth sessions via /dev/crypto now always use ETA
mode. The COP_F_CIPHER_FIRST flag is now a no-op that is ignored.
This was actually documented as being true in crypto(4) before, but
the code had not implemented this before I added the CIPHER_FIRST
flag.
- I have not yet updated /dev/crypto to be aware of explicit modes for
sessions. I will probably do that at some point in the future as well
as teach it about IV/nonce and tag lengths for AEAD so we can support
all of the NIST KAT tests for GCM and CCM.
- I've split up the exising crypto.9 manpage into several pages
of which many are written from scratch.
- I have converted all drivers and consumers in the tree and verified
that they compile, but I have not tested all of them. I have tested
the following drivers:
- cryptosoft
- aesni (AES only)
- blake2
- ccr
and the following consumers:
- cryptodev
- IPsec
- ktls_ocf
- GELI (lightly)
I have not tested the following:
- ccp
- aesni with sha
- hifn
- kgssapi_krb5
- ubsec
- padlock
- safe
- armv8_crypto (aarch64)
- glxsb (i386)
- sec (ppc)
- cesa (armv7)
- cryptocteon (mips64)
- nlmsec (mips64)
Discussed with: cem
Relnotes: yes
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D23677
Negative lengths are always invalid. The key length should also
be zero for hash algorithms that do not accept a key.
admbugs: 949
Reported by: Yuval Kanarenstein <yuvalk@ssd-disclosure.com>
Reviewed by: cem
MFC after: 1 week
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D23094
This prevents use-after-free races with crypto requests (which may
sleep) and CIOCFSESSION as well as races from current CIOCFSESSION
requests.
admbugs: 949
Reported by: Yuval Kanarenstein <yuvalk@ssd-disclosure.com>
Reviewed by: cem
MFC after: 1 week
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D23077
Warn when actual operations are performed instead of when sessions are
created. The /dev/crypto engine in OpenSSL 1.0.x tries to create
sessions for all possible algorithms each time it is initialized
resulting in spurious warnings.
Reported by: Mike Tancsa
MFC after: 3 days
Sponsored by: Chelsio Communications
New sysctl/tunables can now set the interval (in seconds) between
rate-limited crypto warnings. The new sysctls are:
- kern.cryptodev_warn_interval for /dev/crypto
- net.inet.ipsec.crypto_warn_interval for IPsec
- kern.kgssapi_warn_interval for KGSSAPI
Reviewed by: cem
MFC after: 1 month
Relnotes: yes
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D20555
These algorithms are deprecated algorithms that will have no in-kernel
consumers in FreeBSD 13. Specifically, deprecate the following
algorithms:
- ARC4
- Blowfish
- CAST128
- DES
- 3DES
- MD5-HMAC
- Skipjack
MFC after: 1 month
Relnotes: yes
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D20554
This commit essentially has three parts:
* Add the AES-CCM encryption hooks. This is in and of itself fairly small,
as there is only a small difference between CCM and the other ICM-based
algorithms.
* Hook the code into the OpenCrypto framework. This is the bulk of the
changes, as the algorithm type has to be checked for, and the differences
between it and GCM dealt with.
* Update the cryptocheck tool to be aware of it. This is invaluable for
confirming that the code works.
This is a software-only implementation, meaning that the performance is very
low.
Sponsored by: iXsystems Inc.
Differential Revision: https://reviews.freebsd.org/D19090
Track session objects in the framework, and pass handles between the
framework (OCF), consumers, and drivers. Avoid redundancy and complexity in
individual drivers by allocating session memory in the framework and
providing it to drivers in ::newsession().
Session handles are no longer integers with information encoded in various
high bits. Use of the CRYPTO_SESID2FOO() macros should be replaced with the
appropriate crypto_ses2foo() function on the opaque session handle.
Convert OCF drivers (in particular, cryptosoft, as well as myriad others) to
the opaque handle interface. Discard existing session tracking as much as
possible (quick pass). There may be additional code ripe for deletion.
Convert OCF consumers (ipsec, geom_eli, krb5, cryptodev) to handle-style
interface. The conversion is largely mechnical.
The change is documented in crypto.9.
Inspired by
https://lists.freebsd.org/pipermail/freebsd-arch/2018-January/018835.html .
No objection from: ae (ipsec portion)
Reported by: jhb
In part, to support OpenSSL's use of cryptodev, which puts the HMAC pieces
in software and only offloads the raw hash primitive.
The following cryptodev identifiers are added:
* CRYPTO_RIPEMD160 (not hooked up)
* CRYPTO_SHA2_224
* CRYPTO_SHA2_256
* CRYPTO_SHA2_384
* CRYPTO_SHA2_512
The plain SHA1 and 2 hashes are plumbed through cryptodev (feels like there
is a lot of redundancy here...) and cryptosoft.
This adds new auth_hash implementations for the plain hashes, as well as
SHA1 (which had a cryptodev.h identifier, but no implementation).
Add plain SHA 1 and 2 hash tests to the cryptocheck tool.
Motivation stems from John Baldwin's earlier OCF email,
https://lists.freebsd.org/pipermail/freebsd-arch/2018-January/018835.html .
opt_compat.h is mentioned in nearly 180 files. In-progress network
driver compabibility improvements may add over 100 more so this is
closer to "just about everywhere" than "only some files" per the
guidance in sys/conf/options.
Keep COMPAT_LINUX32 in opt_compat.h as it is confined to a subset of
sys/compat/linux/*.c. A fake _COMPAT_LINUX option ensure opt_compat.h
is created on all architectures.
Move COMPAT_LINUXKPI to opt_dontuse.h as it is only used to control the
set of compiled files.
Reviewed by: kib, cem, jhb, jtl
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D14941
Mostly this is a thin shim around existing code to integrate with enc_xform
and cryptosoft (+ cryptodev).
Expand the cryptodev buffer used to match that of Chacha20's native block
size as a performance enhancement for chacha20_xform_crypt_multi.
No functional change for Skipjack, AES-ICM, Blowfish, CAST-128, Camellia,
DES3, Rijndael128, DES. All of these have identical IV and blocksizes
declared in the associated enc_xform.
Functional changes for:
* AES-GCM: block len of 1, IV len of 12
* AES-XTS: block len of 16, IV len of 8
* NULL: block len of 4, IV len of 0
For these, it seems like the IV specified in the enc_xform is correct (and
the blocksize used before was wrong).
Additionally, the not-yet-OCFed cipher Chacha20 has a logical block length
of 1 byte, and a 16 byte IV + nonce.
Rationalize references to IV lengths to refer to the declared ivsize, rather
than declared blocksize.
Sponsored by: Dell EMC Isilon
The upstream repository is on github BLAKE2/libb2. Files landed in
sys/contrib/libb2 are the unmodified upstream files, except for one
difference: secure_zero_memory's contents have been replaced with
explicit_bzero() only because the previous implementation broke powerpc
link. Preferential use of explicit_bzero() is in progress upstream, so
it is anticipated we will be able to drop this diff in the future.
sys/crypto/blake2 contains the source files needed to port libb2 to our
build system, a wrapped (limited) variant of the algorithm to match the API
of our auth_transform softcrypto abstraction, incorporation into the Open
Crypto Framework (OCF) cryptosoft(4) driver, as well as an x86 SSE/AVX
accelerated OCF driver, blake2(4).
Optimized variants of blake2 are compiled for a number of x86 machines
(anything from SSE2 to AVX + XOP). On those machines, FPU context will need
to be explicitly saved before using blake2(4)-provided algorithms directly.
Use via cryptodev / OCF saves FPU state automatically, and use via the
auth_transform softcrypto abstraction does not use FPU.
The intent of the OCF driver is mostly to enable testing in userspace via
/dev/crypto. ATF tests are added with published KAT test vectors to
validate correctness.
Reviewed by: jhb, markj
Obtained from: github BLAKE2/libb2
Differential Revision: https://reviews.freebsd.org/D14662
Create a struct cryptop_data which contains state needed for a single
symmetric crypto operation and move that state out of the session. This
closes a race with the CRYPTO_F_DONE flag that can result in use after
free.
While here, remove the 'cse->error' member. It was just a copy of
'crp->crp_etype' and cryptodev_op() and cryptodev_aead() checked both
'crp->crp_etype' and 'cse->error'. Similarly, do not check for an
error from mtx_sleep() since it is not used with PCATCH or a timeout
so cannot fail with an error.
PR: 218597
Reviewed by: kib
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D13928
Just copyin the IV into the crypto descriptor directly. This avoids
copying the IV twice for each operation.
Reviewed by: kib
MFC after: 2 weeks
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D13847
In particular, no probes were present for AEAD requests, but also for
some other error cases in other ioctl requests.
MFC after: 2 weeks
Sponsored by: Chelsio Communications
Theoretically, HMACs do not actually have any limit on key sizes.
Transforms should compact input keys larger than the HMAC block size by
using the transform (hash) on the input key.
(Short input keys are padded out with zeros to the HMAC block size.)
Still, not all FreeBSD crypto drivers that provide HMAC functionality
handle longer-than-blocksize keys appropriately, so enforce a "maximum" key
length in the crypto API for auth_hashes that previously expressed a
requirement. (The "maximum" is the size of a single HMAC block for the
given transform.) Unconstrained auth_hashes are left as-is.
I believe the previous hardcoded sizes were committed in the original
import of opencrypto from OpenBSD and are due to specific protocol
details of IPSec. Note that none of the previous sizes actually matched
the appropriate HMAC block size.
The previous hardcoded sizes made the SHA tests in cryptotest.py
useless for testing FreeBSD crypto drivers; none of the NIST-KAT example
inputs had keys sized to the previous expectations.
The following drivers were audited to check that they handled keys up to
the block size of the HMAC safely:
Software HMAC:
* padlock(4)
* cesa
* glxsb
* safe(4)
* ubsec(4)
Hardware accelerated HMAC:
* ccr(4)
* hifn(4)
* sec(4) (Only supports up to 64 byte keys despite claiming to
support SHA2 HMACs, but validates input key sizes)
* cryptocteon (MIPS)
* nlmsec (MIPS)
* rmisec (MIPS) (Amusingly, does not appear to use key material at
all -- presumed broken)
Reviewed by: jhb (previous version), rlibby (previous version)
Sponsored by: Dell EMC Isilon
Differential Revision: https://reviews.freebsd.org/D12437
In particular, support chaining an AES cipher with an HMAC for a request
including AAD. This permits submitting requests from userland to encrypt
objects like IPSec packets using these algorithms.
In the non-GCM case, the authentication crypto descriptor covers both the
AAD and the ciphertext. The GCM case remains unchanged. This matches
the requests created internally in IPSec. For the non-GCM case, the
COP_F_CIPHER_FIRST is also supported since the ordering matters.
Note that while this can be used to simulate IPSec requests from userland,
this ioctl cannot currently be used to perform TLS requests using AES-CBC
and MAC-before-encrypt.
Reviewed by: cem
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D11759
This requests that the cipher be performed before rather than after
the HMAC when both are specified for a single operation.
Reviewed by: cem
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D11757
Software crypto implementations don't care how the buffer is laid out,
but hardware implementations may assume that the AAD is always before
the plain/cipher text and that the hash/tag is immediately after the end
of the plain/cipher text.
In particular, this arrangement matches the layout of both IPSec packets
and TLS frames. Linux's crypto framework also assumes this layout for
AEAD requests.
Reviewed by: cem
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D11758
for counter mode), and AES-GCM. Both of these modes have been added to
the aesni module.
Included is a set of tests to validate that the software and aesni
module calculate the correct values. These use the NIST KAT test
vectors. To run the test, you will need to install a soon to be
committed port, nist-kat that will install the vectors. Using a port
is necessary as the test vectors are around 25MB.
All the man pages were updated. I have added a new man page, crypto.7,
which includes a description of how to use each mode. All the new modes
and some other AES modes are present. It would be good for someone
else to go through and document the other modes.
A new ioctl was added to support AEAD modes which AES-GCM is one of them.
Without this ioctl, it is not possible to test AEAD modes from userland.
Add a timing safe bcmp for use to compare MACs. Previously we were using
bcmp which could leak timing info and result in the ability to forge
messages.
Add a minor optimization to the aesni module so that single segment
mbufs don't get copied and instead are updated in place. The aesni
module needs to be updated to support blocked IO so segmented mbufs
don't have to be copied.
We require that the IV be specified for all calls for both GCM and ICM.
This is to ensure proper use of these functions.
Obtained from: p4: //depot/projects/opencrypto
Relnotes: yes
Sponsored by: FreeBSD Foundation
Sponsored by: NetGate
struct kinfo_file.
- Move the various fill_*_info() methods out of kern_descrip.c and into the
various file type implementations.
- Rework the support for kinfo_ofile to generate a suitable kinfo_file object
for each file and then convert that to a kinfo_ofile structure rather than
keeping a second, different set of code that directly manipulates
type-specific file information.
- Remove the shm_path() and ksem_info() layering violations.
Differential Revision: https://reviews.freebsd.org/D775
Reviewed by: kib, glebius (earlier version)
- Add invfo_rdwr() (for read and write), invfo_ioctl(), invfo_poll(),
and invfo_kqfilter() for use by file types that do not support the
respective operations. Home-grown versions of invfo_poll() were
universally broken (they returned an errno value, invfo_poll()
uses poll_no_poll() to return an appropriate event mask). Home-grown
ioctl routines also tended to return an incorrect errno (invfo_ioctl
returns ENOTTY).
- Use the invfo_*() functions instead of local versions for
unsupported file operations.
- Reorder fileops members to match the order in the structure definition
to make it easier to spot missing members.
- Add several missing methods to linuxfileops used by the OFED shim
layer: fo_write(), fo_truncate(), fo_kqfilter(), and fo_stat(). Most
of these used invfo_*(), but a dummy fo_stat() implementation was
added.
This will allow us to more easily test the software versions of these
routines...
Considering that we've never had an software asymetric implmentation,
it's doubtful anyone has this enabled...
to implement fchown(2) and fchmod(2) support for several file types
that previously lacked it. Add MAC entries for chown/chmod done on
posix shared memory and (old) in-kernel posix semaphores.
Based on the submission by: glebius
Reviewed by: rwatson
Approved by: re (bz)