pointer in a local thread. While this is unlikely to significantly
improve performance given modern compiler behavior, it makes the code
more readable and reduces diffs to the Mac OS X version of the same
code (which stores things in creds in the same way, but where the
cred for a thread is reached quite differently).
Discussed with: sson
MFC after: 1 month
Sponsored by: Apple Inc.
Obtained from: TrustedBSD Project
queue length variables as well, avoiding storing the limit in a larger
type than the length.
Submitted by: sson
Sponsored by: Apple Inc.
MFC after: 1 week
regular header tokens. The extended header tokens contain an IP
or IPv6 address which makes it possible to identify which host an
audit record came from when audit records are centralized.
If the host information has not been specified, the system will
default to the old style headers. Otherwise, audit records that
are created as a result of system calls will contain host information.
This implemented has been designed to be consistent with the Solaris
implementation. Host information is set/retrieved using the A_GETKAUDIT
and A_SETKAUDIT auditon(2) commands. These commands require that a
pointer to a auditinfo_addr_t object is passed. Currently only IP and
IPv6 address families are supported.
The users pace bits associated with this change will follow in an
openbsm import.
Reviewed by: rwatson, (sson, wsalamon (older version))
MFC after: 1 month
record queue, so move the offset field from the per-record
audit_pipe_entry structure to the audit_pipe structure.
Now that we support reading more than one record at a time, add a
new summary field to audit_pipe, ap_qbyteslen, which tracks the
total number of bytes present in a pipe, and return that (minus
the current offset) via FIONREAD and kqueue's data variable for
the pending byte count rather than the number of bytes remaining
in only the first record.
Add a number of asserts to confirm that these counts and offsets
following the expected rules.
MFC after: 2 months
Sponsored by: Apple, Inc.
read(2), which meant that records longer than the buffer passed to read(2)
were dropped. Instead take the approach of allowing partial reads to be
continued across multiple system calls more in the style of streaming
character device.
This means retaining a record on the per-pipe queue in a partially read
state, so maintain a current offset into the record. Keep the record on
the queue during a read, so add a new lock, ap_sx, to serialize removal
of records from the queue by either read(2) or ioctl(2) requesting a pipe
flush. Modify the kqueue handler to return bytes left in the current
record rather than simply the size of the current record.
It is now possible to use praudit, which used the standard FILE * buffer
sizes, to track much larger record sizes from /dev/auditpipe, such as
very long command lines to execve(2).
MFC after: 2 months
Sponsored by: Apple, Inc.
pipe has overflowed, drop the newest, rather than oldest, record. This
makes overflow drop behavior consistent with memory allocation failure
leading to drop, avoids touching the consumer end of the queue from a
producer, and lowers the CPU overhead of dropping a record by dropping
before memory allocation and copying.
Obtained from: Apple, Inc.
MFC after: 2 months
protecting the list of audit pipes, and a per-pipe mutex protecting the
queue.
Likewise, replace the single global condition variable used to signal
delivery of a record to one or more pipes, and add a per-pipe condition
variable to avoid spurious wakeups when event subscriptions differ
across multiple pipes.
This slightly increases the cost of delivering to audit pipes, but should
reduce lock contention in the presence of multiple readers as only the
per-pipe lock is required to read from a pipe, as well as avoid
overheading when different pipes are used in different ways.
MFC after: 2 months
Sponsored by: Apple, Inc.
mutex, as it's rarely changed but frequently accessed read-only from
multiple threads, so a potentially significant source of contention.
MFC after: 1 month
Sponsored by: Apple, Inc.
access control checks in mac_bsdextended are not in the same
namespace as the MBI_ flags used in ugidfw policies, so add an
explicit conversion routine to get from one to the other.
Obtained from: TrustedBSD Project
to add more V* constants, and the variables changed by this patch were often
being assigned to mode_t variables, which is 16 bit.
Approved by: rwatson (mentor)
memory mappings when the MAC label on a process changes, to
mac_proc_vm_revoke(),
It now also acquires its own credential reference directly from the
affected process rather than accepting one passed by the the caller,
simplifying the API and consumer code.
Obtained from: TrustedBSD Project
that they operate directly on credentials: mac_proc_create_swapper(),
mac_proc_create_init(), and mac_proc_associate_nfsd(). Update policies.
Obtained from: TrustedBSD Project
be a no-op request, and why this might have to change if we want to allow
leaving a partition someday.
Obtained from: TrustedBSD Project
MFC after: 3 days
control logic and policy registration remaining in that file, and access
control checks broken out into other files by class of check.
Obtained from: TrustedBSD Project
fragment reassembly queues.
This allows policies to label reassembly queues, perform access
control checks when matching fragments to a queue, update a queue
label when fragments are matched, and label the resulting
reassembled datagram.
Obtained from: TrustedBSD Project
When I changed kern_conf.c three months ago I made device unit numbers
equal to (unneeded) device minor numbers. We used to require
bitshifting, because there were eight bits in the middle that were
reserved for a device major number. Not very long after I turned
dev2unit(), minor(), unit2minor() and minor2unit() into macro's.
The unit2minor() and minor2unit() macro's were no-ops.
We'd better not remove these four macro's from the kernel, because there
is a lot of (external) code that may still depend on them. For now it's
harmless to remove all invocations of unit2minor() and minor2unit().
Reviewed by: kib
years by the priv_check(9) interface and just very few places are left.
Note that compatibility stub with older FreeBSD version
(all above the 8 limit though) are left in order to reduce diffs against
old versions. It is responsibility of the maintainers for any module, if
they think it is the case, to axe out such cases.
This patch breaks KPI so __FreeBSD_version will be bumped into a later
commit.
This patch needs to be credited 50-50 with rwatson@ as he found time to
explain me how the priv_check() works in detail and to review patches.
Tested by: Giovanni Trematerra <giovanni dot trematerra at gmail dot com>
Reviewed by: rwatson
appropriate even if Solaris doesn't document it (E2BIG) or use it
(EOVERFLOW).
Submitted by: nectar at apple dot com
Sponsored by: Apple, Inc.
MFC after: 3 days
(1) Abstract interpreter vnode labeling in execve(2) and mac_execve(2)
so that the general exec code isn't aware of the details of
allocating, copying, and freeing labels, rather, simply passes in
a void pointer to start and stop functions that will be used by
the framework. This change will be MFC'd.
(2) Introduce a new flags field to the MAC_POLICY_SET(9) interface
allowing policies to declare which types of objects require label
allocation, initialization, and destruction, and define a set of
flags covering various supported object types (MPC_OBJECT_PROC,
MPC_OBJECT_VNODE, MPC_OBJECT_INPCB, ...). This change reduces the
overhead of compiling the MAC Framework into the kernel if policies
aren't loaded, or if policies require labels on only a small number
or even no object types. Each time a policy is loaded or unloaded,
we recalculate a mask of labeled object types across all policies
present in the system. Eliminate MAC_ALWAYS_LABEL_MBUF option as it
is no longer required.
MFC after: 1 week ((1) only)
Reviewed by: csjp
Obtained from: TrustedBSD Project
Sponsored by: Apple, Inc.
space provided by its argument structure, return EOVERFLOW instead of
E2BIG. The latter is documented in Solaris's man page, but the
former is implemented. In either case, the caller should use
getaudit_addr(2) to return the IPv6 address.
Submitted by: sson
Obtained from: Apple, Inc.
MFC after: 3 days
It is possible that the audit pipe(s) have different preselection configs
then the global preselection mask.
Spotted by: Vincenzo Iozzo
MFC after: 2 weeks
return success if the passed vnode pointer is NULL (rather than
panicking). This can occur if either audit or accounting are
disabled while the policy is running.
Since the swapoff control has no real relevance to this policy,
which is concerned about intent to write rather than water under the
bridge, remove it.
PR: kern/126100
Reported by: Alan Amesbury <amesbury at umn dot edu>
MFC after: 3 days
processes are not producing absolute pathname tokens. It is required
that audited pathnames are generated relative to the global root mount
point. This modification changes our implementation of audit_canon_path(9)
and introduces a new function: vn_fullpath_global(9) which performs a
vnode -> pathname translation relative to the global mount point based
on the contents of the name cache. Much like vn_fullpath,
vn_fullpath_global is a wrapper function which called vn_fullpath1.
Further, the string parsing routines have been converted to use the
sbuf(9) framework. This change also removes the conditional acquisition
of Giant, since the vn_fullpath1 method will not dip into file system
dependent code.
The vnode locking was modified to use vhold()/vdrop() instead the vref()
and vrele(). This will modify the hold count instead of modifying the
user count. This makes more sense since it's the kernel that requires
the reference to the vnode. This also makes sure that the vnode does not
get recycled we hold the reference to it. [1]
Discussed with: rwatson
Reviewed by: kib [1]
MFC after: 2 weeks
semaphores. Specifically, semaphores are now represented as new file
descriptor type that is set to close on exec. This removes the need for
all of the manual process reference counting (and fork, exec, and exit
event handlers) as the normal file descriptor operations handle all of
that for us nicely. It is also suggested as one possible implementation
in the spec and at least one other OS (OS X) uses this approach.
Some bugs that were fixed as a result include:
- References to a named semaphore whose name is removed still work after
the sem_unlink() operation. Prior to this patch, if a semaphore's name
was removed, valid handles from sem_open() would get EINVAL errors from
sem_getvalue(), sem_post(), etc. This fixes that.
- Unnamed semaphores created with sem_init() were not cleaned up when a
process exited or exec'd. They were only cleaned up if the process
did an explicit sem_destroy(). This could result in a leak of semaphore
objects that could never be cleaned up.
- On the other hand, if another process guessed the id (kernel pointer to
'struct ksem' of an unnamed semaphore (created via sem_init)) and had
write access to the semaphore based on UID/GID checks, then that other
process could manipulate the semaphore via sem_destroy(), sem_post(),
sem_wait(), etc.
- As part of the permission check (UID/GID), the umask of the proces
creating the semaphore was not honored. Thus if your umask denied group
read/write access but the explicit mode in the sem_init() call allowed
it, the semaphore would be readable/writable by other users in the
same group, for example. This includes access via the previous bug.
- If the module refused to unload because there were active semaphores,
then it might have deregistered one or more of the semaphore system
calls before it noticed that there was a problem. I'm not sure if
this actually happened as the order that modules are discovered by the
kernel linker depends on how the actual .ko file is linked. One can
make the order deterministic by using a single module with a mod_event
handler that explicitly registers syscalls (and deregisters during
unload after any checks). This also fixes a race where even if the
sem_module unloaded first it would have destroyed locks that the
syscalls might be trying to access if they are still executing when
they are unloaded.
XXX: By the way, deregistering system calls doesn't do any blocking
to drain any threads from the calls.
- Some minor fixes to errno values on error. For example, sem_init()
isn't documented to return ENFILE or EMFILE if we run out of semaphores
the way that sem_open() can. Instead, it should return ENOSPC in that
case.
Other changes:
- Kernel semaphores now use a hash table to manage the namespace of
named semaphores nearly in a similar fashion to the POSIX shared memory
object file descriptors. Kernel semaphores can now also have names
longer than 14 chars (up to MAXPATHLEN) and can include subdirectories
in their pathname.
- The UID/GID permission checks for access to a named semaphore are now
done via vaccess() rather than a home-rolled set of checks.
- Now that kernel semaphores have an associated file object, the various
MAC checks for POSIX semaphores accept both a file credential and an
active credential. There is also a new posixsem_check_stat() since it
is possible to fstat() a semaphore file descriptor.
- A small set of regression tests (using the ksem API directly) is present
in src/tools/regression/posixsem.
Reported by: kris (1)
Tested by: kris
Reviewed by: rwatson (lightly)
MFC after: 1 month
same as the global variable defined in ip_input.c. Instead, adopt the name
'q' as found in about 1/2 of uses in ip_input.c, preventing a collision on
the name. This is non-harmful, but means that search and replace on the
global works less well (as in the virtualization work), as well as indexing
tools.
MFC after: 1 week
Reported by: julian
Except for the case where we use the cloner library (clone_create() and
friends), there is no reason to enforce a unique device minor number
policy. There are various drivers in the source tree that allocate unr
pools and such to provide minor numbers, without using them themselves.
Because we still need to support unique device minor numbers for the
cloner library, introduce a new flag called D_NEEDMINOR. All cdevsw's
that are used in combination with the cloner library should be marked
with this flag to make the cloning work.
This means drivers can now freely use si_drv0 to store their own flags
and state, making it effectively the same as si_drv1 and si_drv2. We
still keep the minor() and dev2unit() routines around to make drivers
happy.
The NTFS code also used the minor number in its hash table. We should
not do this anymore. If the si_drv0 field would be changed, it would no
longer end up in the same list.
Approved by: philip (mentor)
which label mbufs. This leak can occur if one policy successfully allocates
label storage and subsequent allocations from other policies fail.
Spotted by: rwatson
MFC after: 1 week
than checking whether audit is enabled globally, instead check whether
the current thread has an audit record. This avoids entering the audit
code to collect argument data if auditing is enabled but the current
system call is not of interest to audit.
MFC after: 1 week
Sponsored by: Apple, Inc.
exit requires entering the audit code. The result is much the same,
but they mean different things.
MFC afer: 3 days
Submitted by: Diego Giagio <dgiagio at gmail dot com>
explicitly select write locking for all use of the inpcb mutex.
Update some pcbinfo lock assertions to assert locked rather than
write-locked, although in practice almost all uses of the pcbinfo
rwlock main exclusive, and all instances of inpcb lock acquisition
are exclusive.
This change should introduce (ideally) little functional change.
However, it lays the groundwork for significantly increased
parallelism in the TCP/IP code.
MFC after: 3 months
Tested by: kris (superset of committered patch)
after each SYSINIT() macro invocation. This makes a number of
lightweight C parsers much happier with the FreeBSD kernel
source, including cflow's prcc and lxr.
MFC after: 1 month
Discussed with: imp, rink
returns EINVAL. Right now we return 0 or success for invalid commands,
which could be quite problematic in certain conditions.
MFC after: 1 week
Discussed with: rwatson
a queue entry field, just copy out the unsigned int that is the trigger
message. In practice, auditd always requested sizeof(unsigned int), so
the extra bytes were ignored, but copying them out was not the intent.
MFC after: 1 month
global audit mutex and condition variables, with an sx lock which protects
the trail vnode and credential while in use, and is acquired by the system
call code when rotating the trail. Previously, a "message" would be sent
to the kernel audit worker, which did the rotation, but the new code is
simpler and (hopefully) less error-prone.
Obtained from: TrustedBSD Project
MFC after: 1 month
This makes sure that process tokens credentials with un-initialized
audit contexts are handled correctly. Currently, when invariants are
enabled, this change fixes a panic by ensuring that we have a valid
termid family. Also, this fixes token generation for process tokens
making sure that userspace is always getting a valid token.
This is consistent with what Solaris does when an audit context is
un-initialized.
Obtained from: TrustedBSD Project
MFC after: 1 week
relabel check for MLS rather than returning 0 directly.
This problem didn't result in a vulnerability currently as the central
implementation of ifnet relabeling also checks for UNIX privilege, and
we currently don't guarantee containment for the root user in mac_mls,
but we should be using the MLS definition of privilege as well as the
UNIX definition in anticipation of supporting root containment at some
point.
MFC after: 3 days
Submitted by: Zhouyi Zhou <zhouzhouyi at gmail dot com>
Sponsored by: Google SoC 2007
"BSM conversion requested for unknown event 43140"
It should be noted that we need to audit the fd argument for this system
call.
Obtained from: TrustedBSD Project
MFC after: 1 week
conjuction with 'thread' argument passing which is always curthread.
Remove the unuseful extra-argument and pass explicitly curthread to lower
layer functions, when necessary.
KPI results broken by this change, which should affect several ports, so
version bumping and manpage update will be further committed.
Tested by: kris, pho, Diego Sardina <siarodx at gmail dot com>
