Commit Graph

325 Commits

Author SHA1 Message Date
Robert Watson
4b908c8bb4 Add a MAC label, MAC Framework, and MAC policy entry points for IPv6
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
2008-10-26 22:45:18 +00:00
Bjoern A. Zeeb
37ee72936b Add mac_inpcb_check_visible MAC Framework entry point, which is similar
to mac_socket_check_visible but operates on the inpcb.

Reviewed by:	rwatson
MFC after:	3 months (set timer, decide then)
2008-10-17 12:54:28 +00:00
Robert Watson
6356dba0b4 Introduce two related changes to the TrustedBSD MAC Framework:
(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.
2008-08-23 15:26:36 +00:00
John Baldwin
6bc1e9cd84 Rework the lifetime management of the kernel implementation of POSIX
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
2008-06-27 05:39:04 +00:00
John Baldwin
c4f3a35a54 Remove the posixsem_check_destroy() MAC check. It is semantically identical
to doing a MAC check for close(), but no other types of close() (including
close(2) and ksem_close(2)) have MAC checks.

Discussed with:	rwatson
2008-06-23 21:37:53 +00:00
Robert Watson
37f44cb428 The TrustedBSD MAC Framework named struct ipq instances 'ipq', which is the
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
2008-06-13 22:14:15 +00:00
Christian S.J. Peron
1f84ab0f2a Plug a memory leak which can occur when multiple MAC policies are loaded
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
2008-05-27 14:18:02 +00:00
Robert Watson
211b72ad2f When propagating a MAC label from an inpcb to an mbuf, allow read and
write locks on the inpcb, not just write locks.

MFC after:	3 months
2008-04-19 18:35:27 +00:00
Robert Watson
8501a69cc9 Convert pcbinfo and inpcb mutexes to rwlocks, and modify macros to
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)
2008-04-17 21:38:18 +00:00
Robert Watson
646a9f8029 Make naming of include guards for MAC Framework include files more
consistent with other kernel include guards (don't start with _SYS).

MFC after:	3 days
2008-04-13 21:45:52 +00:00
Konstantin Belousov
57b4252e45 Add the support for the AT_FDCWD and fd-relative name lookups to the
namei(9).

Based on the submission by rdivacky,
	sponsored by Google Summer of Code 2007
Reviewed by:	rwatson, rdivacky
Tested by:	pho
2008-03-31 12:01:21 +00:00
Attilio Rao
22db15c06f VOP_LOCK1() (and so VOP_LOCK()) and VOP_UNLOCK() are only used in
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>
2008-01-13 14:44:15 +00:00
Attilio Rao
cb05b60a89 vn_lock() is currently only used with the 'curthread' passed as argument.
Remove this argument and pass curthread directly to underlying
VOP_LOCK1() VFS method. This modify makes the code cleaner and in
particular remove an annoying dependence helping next lockmgr() cleanup.
KPI results, obviously, changed.

Manpage and FreeBSD_version will be updated through further commits.

As a side note, would be valuable to say that next commits will address
a similar cleanup about VFS methods, in particular vop_lock1 and
vop_unlock.

Tested by:	Diego Sardina <siarodx at gmail dot com>,
		Andrea Di Pasquale <whyx dot it at gmail dot com>
2008-01-10 01:10:58 +00:00
John Baldwin
8e38aeff17 Add a new file descriptor type for IPC shared memory objects and use it to
implement shm_open(2) and shm_unlink(2) in the kernel:
- Each shared memory file descriptor is associated with a swap-backed vm
  object which provides the backing store.  Each descriptor starts off with
  a size of zero, but the size can be altered via ftruncate(2).  The shared
  memory file descriptors also support fstat(2).  read(2), write(2),
  ioctl(2), select(2), poll(2), and kevent(2) are not supported on shared
  memory file descriptors.
- shm_open(2) and shm_unlink(2) are now implemented as system calls that
  manage shared memory file descriptors.  The virtual namespace that maps
  pathnames to shared memory file descriptors is implemented as a hash
  table where the hash key is generated via the 32-bit Fowler/Noll/Vo hash
  of the pathname.
- As an extension, the constant 'SHM_ANON' may be specified in place of the
  path argument to shm_open(2).  In this case, an unnamed shared memory
  file descriptor will be created similar to the IPC_PRIVATE key for
  shmget(2).  Note that the shared memory object can still be shared among
  processes by sharing the file descriptor via fork(2) or sendmsg(2), but
  it is unnamed.  This effectively serves to implement the getmemfd() idea
  bandied about the lists several times over the years.
- The backing store for shared memory file descriptors are garbage
  collected when they are not referenced by any open file descriptors or
  the shm_open(2) virtual namespace.

Submitted by:	dillon, peter (previous versions)
Submitted by:	rwatson (I based this on his version)
Reviewed by:	alc (suggested converting getmemfd() to shm_open())
2008-01-08 21:58:16 +00:00
Robert Watson
b5f992b93d Fix a MAC label leak for POSIX semaphores, in which per-policy labels
would be properly disposed of, but the global label structure for the
semaphore wouldn't be freed.

MFC after:	3 days
Reported by:	tanyong <tanyong at ercist dot iscas dot ac dot cn>,
		zhouzhouyi
2007-12-17 17:26:32 +00:00
Robert Watson
2a9e17ce8e Garbage collect mac_mbuf_create_multicast_encap TrustedBSD MAC Framework
entry point, which is no longer required now that we don't support
old-style multicast tunnels.  This removes the last mbuf object class
entry point that isn't init/copy/destroy.

Obtained from:	TrustedBSD Project
2007-10-28 17:55:57 +00:00
Robert Watson
a13e21f7bc Continue to move from generic network entry points in the TrustedBSD MAC
Framework by moving from mac_mbuf_create_netlayer() to more specific
entry points for specific network services:

- mac_netinet_firewall_reply() to be used when replying to in-bound TCP
  segments in pf and ipfw (etc).

- Rename mac_netinet_icmp_reply() to mac_netinet_icmp_replyinplace() and
  add mac_netinet_icmp_reply(), reflecting that in some cases we overwrite
  a label in place, but in others we apply the label to a new mbuf.

Obtained from:	TrustedBSD Project
2007-10-28 17:12:48 +00:00
Robert Watson
b9b0dac33b Move towards more explicit support for various network protocol stacks
in the TrustedBSD MAC Framework:

- Add mac_atalk.c and add explicit entry point mac_netatalk_aarp_send()
  for AARP packet labeling, rather than using a generic link layer
  entry point.

- Add mac_inet6.c and add explicit entry point mac_netinet6_nd6_send()
  for ND6 packet labeling, rather than using a generic link layer entry
  point.

- Add expliict entry point mac_netinet_arp_send() for ARP packet
  labeling, and mac_netinet_igmp_send() for IGMP packet labeling,
  rather than using a generic link layer entry point.

- Remove previous genering link layer entry point,
  mac_mbuf_create_linklayer() as it is no longer used.

- Add implementations of new entry points to various policies, largely
  by replicating the existing link layer entry point for them; remove
  old link layer entry point implementation.

- Make MAC_IFNET_LOCK(), MAC_IFNET_UNLOCK(), and mac_ifnet_mtx global
  to the MAC Framework rather than static to mac_net.c as it is now
  needed outside of mac_net.c.

Obtained from:	TrustedBSD Project
2007-10-28 15:55:23 +00:00
Robert Watson
6683b28d78 Update comment following MAC Framework entry point renaming and
reorganization.

Obtained from:	TrustedBSD Project
2007-10-26 21:16:34 +00:00
Robert Watson
8640764682 Rename 'mac_mbuf_create_from_firewall' to 'mac_netinet_firewall_send' as
we move towards netinet as a pseudo-object for the MAC Framework.

Rename 'mac_create_mbuf_linklayer' to 'mac_mbuf_create_linklayer' to
reflect general object-first ordering preference.

Sponsored by:	SPARTA (original patches against Mac OS X)
Obtained from:	TrustedBSD Project, Apple Computer
2007-10-26 13:18:38 +00:00
Robert Watson
179da74eb8 Sort entry points in mac_framework.h and mac_policy.h alphabetically by
primary object type, and then by secondarily by method name.  This sorts
entry points relating to particular objects, such as pipes, sockets, and
vnodes together.

Sponsored by:	SPARTA (original patches against Mac OS X)
Obtained from:	TrustedBSD Project, Apple Computer
2007-10-25 22:45:25 +00:00
Robert Watson
02be6269c3 Normalize TCP syncache-related MAC Framework entry points to match most
other entry points in the form mac_<object>_method().

Discussed with:	csjp
Obtained from:	TrustedBSD Project
2007-10-25 14:37:37 +00:00
Robert Watson
eb2cd5e1df Rename mac_associate_nfsd_label() to mac_proc_associate_nfsd(), and move
from mac_vfs.c to mac_process.c to join other functions that setup up
process labels for specific purposes.  Unlike the two proc create calls,
this call is intended to run after creation when a process registers as
the NFS daemon, so remains an _associate_ call..

Obtained from:	TrustedBSD Project
2007-10-25 12:34:14 +00:00
Robert Watson
a7f3aac7cb Further MAC Framework cleanup: normalize some local variable names and
clean up some comments.

Obtained from:	TrustedBSD Project
2007-10-25 07:49:47 +00:00
Robert Watson
30d239bc4c Merge first in a series of TrustedBSD MAC Framework KPI changes
from Mac OS X Leopard--rationalize naming for entry points to
the following general forms:

  mac_<object>_<method/action>
  mac_<object>_check_<method/action>

The previous naming scheme was inconsistent and mostly
reversed from the new scheme.  Also, make object types more
consistent and remove spaces from object types that contain
multiple parts ("posix_sem" -> "posixsem") to make mechanical
parsing easier.  Introduce a new "netinet" object type for
certain IPv4/IPv6-related methods.  Also simplify, slightly,
some entry point names.

All MAC policy modules will need to be recompiled, and modules
not updates as part of this commit will need to be modified to
conform to the new KPI.

Sponsored by:	SPARTA (original patches against Mac OS X)
Obtained from:	TrustedBSD Project, Apple Computer
2007-10-24 19:04:04 +00:00
Robert Watson
1cb99cfc25 Bump MAC_VERSION to 4 and add an 8.x line in the version table. Version 4
will include significant synchronization to the Mac OS X Leopard version
of the MAC Framework.

Obtained from:	TrustedBSD Project
2007-10-23 14:12:16 +00:00
Robert Watson
fe09513e7d Canonicalize naming of local variables for struct ksem and associated
labels to 'ks' and 'kslabel' to reflect the convention in posix_sem.c.

MFC after:	3 days
Obtained from:	TrustedBSD Project
2007-10-21 11:11:07 +00:00
Robert Watson
45e0f3d63d Rename mac_check_vnode_delete() MAC Framework and MAC Policy entry
point to mac_check_vnode_unlink(), reflecting UNIX naming conventions.

This is the first of several commits to synchronize the MAC Framework
in FreeBSD 7.0 with the MAC Framework as it will appear in Mac OS X
Leopard.

Reveiwed by:    csjp, Samy Bahra <sbahra at gwu dot edu>
Submitted by:   Jacques Vidrine <nectar at apple dot com>
Obtained from:  Apple Computer, Inc.
Sponsored by:   SPARTA, SPAWAR
Approved by:    re (bmah)
2007-09-10 00:00:18 +00:00
Robert Watson
0bf686c125 Remove the now-unused NET_{LOCK,UNLOCK,ASSERT}_GIANT() macros, which
previously conditionally acquired Giant based on debug.mpsafenet.  As that
has now been removed, they are no longer required.  Removing them
significantly simplifies error-handling in the socket layer, eliminated
quite a bit of unwinding of locking in error cases.

While here clean up the now unneeded opt_net.h, which previously was used
for the NET_WITH_GIANT kernel option.  Clean up some related gotos for
consistency.

Reviewed by:	bz, csjp
Tested by:	kris
Approved by:	re (kensmith)
2007-08-06 14:26:03 +00:00
Peter Wemm
343cc83e1b Fix a bunch of warnings due to a missing forward declaration of a struct.
Approved by: re (rwatson)
2007-07-05 06:45:37 +00:00
Robert Watson
f1e8bf6dd4 Add a new MAC framework and policy entry point,
mpo_check_proc_setaudit_addr to be used when controlling use of
setaudit_addr(), rather than mpo_check_proc_setaudit(), which takes a
different argument type.

Reviewed by:	csjp
Approved by:	re (kensmith)
2007-06-26 14:14:01 +00:00
Robert Watson
305759909e Rename mac*devfsdirent*() to mac*devfs*() to synchronize with SEDarwin,
where similar data structures exist to support devfs and the MAC
Framework, but are named differently.

Obtained from:	TrustedBSD Project
Sponsored by:	SPARTA, Inc.
2007-04-23 13:36:54 +00:00
Robert Watson
26ae2b86b6 Normalize variable naming in the MAC Framework by adopting the normal
variable name conventions for arguments passed into the framework --
for example, name network interfaces 'ifp', sockets 'so', mounts 'mp',
mbufs 'm', processes 'p', etc, wherever possible.  Previously there
was significant variation in this regard.

Normalize copyright lists to ranges where sensible.
2007-04-22 19:55:56 +00:00
Robert Watson
eb542415c0 In the MAC Framework implementation, file systems have two per-mountpoint
labels: the mount label (label of the mountpoint) and the fs label (label
of the file system).  In practice, policies appear to only ever use one,
and the distinction is not helpful.

Combine mnt_mntlabel and mnt_fslabel into a single mnt_label, and
eliminate extra machinery required to maintain the additional label.
Update policies to reflect removal of extra entry points and label.

Obtained from:	TrustedBSD Project
Sponsored by:	SPARTA, Inc.
2007-04-22 16:18:10 +00:00
Robert Watson
c14d15ae3e Remove MAC Framework access control check entry points made redundant with
the introduction of priv(9) and MAC Framework entry points for privilege
checking/granting.  These entry points exactly aligned with privileges and
provided no additional security context:

- mac_check_sysarch_ioperm()
- mac_check_kld_unload()
- mac_check_settime()
- mac_check_system_nfsd()

Add mpo_priv_check() implementations to Biba and LOMAC policies, which,
for each privilege, determine if they can be granted to processes
considered unprivileged by those two policies.  These mostly, but not
entirely, align with the set of privileges granted in jails.

Obtained from:	TrustedBSD Project
2007-04-22 15:31:22 +00:00
Robert Watson
18717f69b1 Allow MAC policy modules to control access to audit configuration system
calls.  Add MAC Framework entry points and MAC policy entry points for
audit(), auditctl(), auditon(), setaudit(), aud setauid().

MAC Framework entry points are only added for audit system calls where
additional argument context may be useful for policy decision-making; other
audit system calls without arguments may be controlled via the priv(9)
entry points.

Update various policy modules to implement audit-related checks, and in
some cases, other missing system-related checks.

Obtained from:	TrustedBSD Project
Sponsored by:	SPARTA, Inc.
2007-04-21 22:08:48 +00:00
Robert Watson
0c14ff0eb5 Remove 'MPSAFE' annotations from the comments above most system calls: all
system calls now enter without Giant held, and then in some cases, acquire
Giant explicitly.

Remove a number of other MPSAFE annotations in the credential code and
tweak one or two other adjacent comments.
2007-03-04 22:36:48 +00:00
Robert Watson
0142affc77 Introduce accessor functions mac_label_get() and mac_label_set() to replace
LABEL_TO_SLOT() macro used by policy modules to query and set label data
in struct label.  Instead of using a union, store an intptr_t, simplifying
the API.

Update policies: in most cases this required only small tweaks to current
wrapper macros.  In two cases, a single wrapper macros had to be split into
separate get and set macros.

Move struct label definition from _label.h to mac_internal.h and remove
_label.h.  With this change, policies may now treat struct label * as
opaque, allowing us to change the layout of struct label without breaking
the policy module ABI.  For example, we could make the maximum number of
policies with labels modifiable at boot-time rather than just at
compile-time.

Obtained from:	TrustedBSD Project
2007-02-06 14:19:25 +00:00
Robert Watson
c96ae1968a Continue 7-CURRENT MAC Framework rearrangement and cleanup:
Don't perform a nested include of _label.h in mac.h, as mac.h now
describes only  the user API to MAC, and _label.h defines the in-kernel
representation of MAC labels.

Remove mac.h includes from policies and MAC framework components that do
not use userspace MAC API definitions.

Add _KERNEL inclusion checks to mac_internal.h and mac_policy.h, as these
are kernel-only include files

Obtained from:	TrustedBSD Project
2007-02-06 10:59:23 +00:00
Christian S.J. Peron
22a0de89ff Remove conditional return of 1. For the MAC_STATIC case at this point in
the code, one being returned is invariant.

Discussed with:	rwatson
MFC after:	1 week
2007-01-01 01:40:29 +00:00
Robert Watson
989d409801 Only signal the CV indicating that the MAC Framework is available for
exclusive access if there is at least one thread waiting for it to
become available.  This may significantly reduce overhead by reducing
the number of unnecessary wakeups issued whenever the framework becomes
idle.

Annotate that we still signal the CV more than necessary and should
fix this.

Obtained from:	TrustedBSD Project
Reviewed by:	csjp
Tested by:	csjp
2006-12-31 20:26:20 +00:00
Robert Watson
c441d123ef Slightly resort functions in file so that no forward function prototypes
are required.

Obtained from:	TrustedBSD Project
2006-12-29 20:21:21 +00:00
Robert Watson
39b73a30c0 Re-add include of opt_mac.h in mac_framework.c, which was improperly
removed from this file.  It is required to pick up the definition of
MAC_STATIC.
2006-12-29 20:16:29 +00:00
Robert Watson
d02188c146 Add missing include guards to mac_internal.h, update include guards in
mac_policy.h following move to new location in src/sys/security/mac.

Obtained from:	TrustedBSD Project
2006-12-28 23:23:35 +00:00
Robert Watson
bd8a9c45aa Remove XXX comments about EA transaction support and provide a more
general and detailed comment on the topic of EA transactions and kernel
warnings.

Obtained from:	TrustedBSD Project
2006-12-28 22:02:59 +00:00
Robert Watson
9b637ee9dd Remove an inaccurate comment I added regarding storage for mbuf tag
labels: they are in fact stored in the tag directly.

Obtained from:	TrustedBSD Project
2006-12-28 21:57:59 +00:00
Robert Watson
c982ffa42a In mac_inpcb_sosetlabel(), assert the socket lock rather than commenting
that we should assert the socket lock.

Obtained from:	TrustedBSD Project
2006-12-28 21:56:39 +00:00
Robert Watson
be23ba9aab Centralize definition of MAC_VERSION in mac_policy.h, as it defines the
kernel<->policy ABI version.  Add a comment to the definition describing
it and listing known versions.  Modify MAC_POLICY_SET() to reference the
current kernel version by name rather than by number.

Staticize mac_late, which is used only in mac_framework.c.

Obtained from:	TrustedBSD Project
2006-12-28 21:48:38 +00:00
Robert Watson
d5fb913feb Move mac_init_label() and mac_destroy_label() from mac_framework.c to
mac_label.c, and use these instead of replicated code in the label zone
constructor and destructor.

Obtained from:	TrustedBSD Project
2006-12-28 21:15:37 +00:00
Robert Watson
ef136b272a Trim unneeded includes. 2006-12-28 21:07:45 +00:00
Robert Watson
224a974b9b Break contents of kern_mac.c out into two files following a repo-copy:
mac_framework.c   Contains basic MAC Framework functions, policy
                  registration, sysinits, etc.

mac_syscalls.c    Contains implementations of various MAC system calls,
                  including ENOSYS stubs when compiling without options
                  MAC.

Obtained from:	TrustedBSD Project
2006-12-28 20:52:02 +00:00
Robert Watson
471e5756ad Update MAC Framework general comments, referencing various interfaces it
consumes and implements, as well as the location of the framework and
policy modules.

Refactor MAC Framework versioning a bit so that the current ABI version can
be exported via a read-only sysctl.

Further update comments relating to locking/synchronization.

Update copyright to take into account these and other recent changes.

Obtained from:	TrustedBSD Project
2006-12-28 17:25:57 +00:00
Robert Watson
6baacecd1b Re-wrap comments following de-indentation. 2006-12-23 22:21:13 +00:00
Robert Watson
0efd6615cd Move src/sys/sys/mac_policy.h, the kernel interface between the MAC
Framework and security modules, to src/sys/security/mac/mac_policy.h,
completing the removal of kernel-only MAC Framework include files from
src/sys/sys.  Update the MAC Framework and MAC policy modules.  Delete
the old mac_policy.h.

Third party policy modules will need similar updating.

Obtained from:	TrustedBSD Project
2006-12-22 23:34:47 +00:00
Robert Watson
e009ba461d Minor style fixes. 2006-12-21 09:58:02 +00:00
Robert Watson
e66fe0e1db Remove mac_enforce_subsystem debugging sysctls. Enforcement on
subsystems will be a property of policy modules, which may require
access control check entry points to be invoked even when not actively
enforcing (i.e., to track information flow without providing
protection).

Obtained from:	TrustedBSD Project
Suggested by:	Christopher dot Vance at sparta dot com
2006-12-21 09:51:34 +00:00
Robert Watson
8425ae1208 Comment LABEL_TO_SLOT() macro, including observing that we'd like to improve
this policy API to avoid encoding struct label binary layout in policy
modules.

Obtained from:	TrustedBSD Project
2006-12-20 23:41:59 +00:00
Robert Watson
19d0ec0330 Trim trailing white space, clean up comment line wrapping and formatting.
Document mac_associate_nfsd_label().

Obtained from:	TrustedBSD Project
2006-12-20 23:18:17 +00:00
Robert Watson
27c24b4e88 Trim trailing white space. 2006-12-20 23:17:34 +00:00
Robert Watson
df3c68e479 Document socket labeling model.
Clean up comment white space and wrapping.

Obtained from:	TrustedBSD Project
2006-12-20 23:16:41 +00:00
Robert Watson
1f00b646ec Clean up comment white space and line wrapping. 2006-12-20 23:16:01 +00:00
Robert Watson
23c3d46ae8 Additional comments regarding the interaction between the kernel privilege
model and the MAC Framework.

Obtained from:	TrustedBSD Project
2006-12-20 23:15:27 +00:00
Robert Watson
e678cce940 Document that we could allocate the mbuf label as part of the tag rather
than from the slab, but don't.

Document mac_mbuf_to_label(), mac_copy_mbuf_tag().

Clean up white space/wrapping for other comments.

Obtained from:	TrustedBSD Project
2006-12-20 23:14:33 +00:00
Robert Watson
5c700f29d9 Staticize and comment zone_label.
Obtained from:	TrustedBSD Project
2006-12-20 23:13:04 +00:00
Robert Watson
5c5a98199b Clean up comments, trailing white space.
Provide a comment describing MAC_EXTERNALIZE().

Obtained from:	TrustedBSD Project
2006-12-20 23:12:36 +00:00
Robert Watson
95c8c170f3 Re-wrap comment at 77 character columns. 2006-12-20 23:11:01 +00:00
Robert Watson
9caab7a262 Comment and white space cleanup.
Exapnd comments on System V IPC labeling methods, which could use improved
consistency with respect to other object types.

Obtained from:	TrustedBSD Project
2006-12-20 20:43:19 +00:00
Robert Watson
8f3476b39b Externalize local stack copy of the ifnet label, rather than the copy on
the ifnet itself.  The stack copy has been made while holding the mutex
protecting ifnet labels, so copying from the ifnet copy could result in
an inconsistent version being copied out.

Reported by:	Todd.Miller@sparta.com
Obtained from:	TrustedBSD Project
MFC after:	3 weeks
2006-12-20 20:40:29 +00:00
Robert Watson
17041e6708 Expand commenting on label slots, justification for the MAC Framework locking
model, interactions between locking and policy init/destroy methods.

Rewrap some comments to 77 character line wrap.

Obtained from:	TrustedBSD Project
2006-12-20 20:38:44 +00:00
Christian S.J. Peron
826cef3d75 Fix LOR between the syncache and inpcb locks when MAC is present in the
kernel.  This LOR snuck in with some of the recent syncache changes.  To
fix this, the inpcb handling was changed:

- Hang a MAC label off the syncache object
- When the syncache entry is initially created, we pickup the PCB lock
  is held because we extract information from it while initializing the
  syncache entry.  While we do this, copy the MAC label associated with
  the PCB and use it for the syncache entry.
- When the packet is transmitted, copy the label from the syncache entry
  to the mbuf so it can be processed by security policies which analyze
  mbuf labels.

This change required that the MAC framework be extended to support the
label copy operations from the PCB to the syncache entry, and then from
the syncache entry to the mbuf.

These functions really should be referencing the syncache structure instead
of the label.  However, due to some of the complexities associated with
exposing this syncache structure we operate directly on it's label pointer.
This should be OK since we aren't making any access control decisions within
this code directly, we are merely allocating and copying label storage so
we can properly initialize mbuf labels for any packets the syncache code
might create.

This also has a nice side effect of caching.  Prior to this change, the
PCB would be looked up/locked for each packet transmitted.  Now the label
is cached at the time the syncache entry is initialized.

Submitted by:	andre [1]
Discussed with:	rwatson

[1] andre submitted the tcp_syncache.c changes
2006-12-13 06:00:57 +00:00
Tom Rhodes
6aeb05d7be Merge posix4/* into normal kernel hierarchy.
Reviewed by:	glanced at by jhb
Approved by:	silence on -arch@ and -standards@
2006-11-11 16:26:58 +00:00
Robert Watson
acd3428b7d Sweep kernel replacing suser(9) calls with priv(9) calls, assigning
specific privilege names to a broad range of privileges.  These may
require some future tweaking.

Sponsored by:           nCircle Network Security, Inc.
Obtained from:          TrustedBSD Project
Discussed on:           arch@
Reviewed (at least in part) by: mlaier, jmg, pjd, bde, ceri,
                        Alex Lyashkov <umka at sevcity dot net>,
                        Skip Ford <skip dot ford at verizon dot net>,
                        Antoine Brodin <antoine dot brodin at laposte dot net>
2006-11-06 13:42:10 +00:00
Robert Watson
800c940832 Add a new priv(9) kernel interface for checking the availability of
privilege for threads and credentials.  Unlike the existing suser(9)
interface, priv(9) exposes a named privilege identifier to the privilege
checking code, allowing more complex policies regarding the granting of
privilege to be expressed.  Two interfaces are provided, replacing the
existing suser(9) interface:

suser(td)                 ->   priv_check(td, priv)
suser_cred(cred, flags)   ->   priv_check_cred(cred, priv, flags)

A comprehensive list of currently available kernel privileges may be
found in priv.h.  New privileges are easily added as required, but the
comments on adding privileges found in priv.h and priv(9) should be read
before doing so.

The new privilege interface exposed sufficient information to the
privilege checking routine that it will now be possible for jail to
determine whether a particular privilege is granted in the check routine,
rather than relying on hints from the calling context via the
SUSER_ALLOWJAIL flag.  For now, the flag is maintained, but a new jail
check function, prison_priv_check(), is exposed from kern_jail.c and used
by the privilege check routine to determine if the privilege is permitted
in jail.  As a result, a centralized list of privileges permitted in jail
is now present in kern_jail.c.

The MAC Framework is now also able to instrument privilege checks, both
to deny privileges otherwise granted (mac_priv_check()), and to grant
privileges otherwise denied (mac_priv_grant()), permitting MAC Policy
modules to implement privilege models, as well as control a much broader
range of system behavior in order to constrain processes running with
root privilege.

The suser() and suser_cred() functions remain implemented, now in terms
of priv_check() and the PRIV_ROOT privilege, for use during the transition
and possibly continuing use by third party kernel modules that have not
been updated.  The PRIV_DRIVER privilege exists to allow device drivers to
check privilege without adopting a more specific privilege identifier.

This change does not modify the actual security policy, rather, it
modifies the interface for privilege checks so changes to the security
policy become more feasible.

Sponsored by:		nCircle Network Security, Inc.
Obtained from:		TrustedBSD Project
Discussed on:		arch@
Reviewed (at least in part) by:	mlaier, jmg, pjd, bde, ceri,
			Alex Lyashkov <umka at sevcity dot net>,
			Skip Ford <skip dot ford at verizon dot net>,
			Antoine Brodin <antoine dot brodin at laposte dot net>
2006-11-06 13:37:19 +00:00
Robert Watson
17451386d0 Forward declare struct cdev, since arguments of this type are used in
function prototypes.

Obtained from:	TrustedBSD Project
2006-10-30 15:20:49 +00:00
Robert Watson
f776aa327d Remove extra _MAC_ from #ifdef guard. 2006-10-25 13:14:25 +00:00
Robert Watson
aed5570872 Complete break-out of sys/sys/mac.h into sys/security/mac/mac_framework.h
begun with a repo-copy of mac.h to mac_framework.h.  sys/mac.h now
contains the userspace and user<->kernel API and definitions, with all
in-kernel interfaces moved to mac_framework.h, which is now included
across most of the kernel instead.

This change is the first step in a larger cleanup and sweep of MAC
Framework interfaces in the kernel, and will not be MFC'd.

Obtained from:	TrustedBSD Project
Sponsored by:	SPARTA
2006-10-22 11:52:19 +00:00
Robert Watson
738f14d4b1 Remove MAC_DEBUG label counters, which were used to debug leaks and
other problems while labels were first being added to various kernel
objects.  They have outlived their usefulness.

MFC after:	1 month
Suggested by:	Christopher dot Vance at SPARTA dot com
Obtained from:	TrustedBSD Project
2006-09-20 13:33:41 +00:00
Robert Watson
5702e0965e Declare security and security.bsd sysctl hierarchies in sysctl.h along
with other commonly used sysctl name spaces, rather than declaring them
all over the place.

MFC after:	1 month
Sponsored by:	nCircle Network Security, Inc.
2006-09-17 20:00:36 +00:00
Christian S.J. Peron
d94f2a68f8 Introduce a new entry point, mac_create_mbuf_from_firewall. This entry point
exists to allow the mandatory access control policy to properly initialize
mbufs generated by the firewall. An example where this might happen is keep
alive packets, or ICMP error packets in response to other packets.

This takes care of kernel panics associated with un-initialize mbuf labels
when the firewall generates packets.

[1] I modified this patch from it's original version, the initial patch
    introduced a number of entry points which were programmatically
    equivalent. So I introduced only one. Instead, we should leverage
    mac_create_mbuf_netlayer() which is used for similar situations,
    an example being icmp_error()

    This will minimize the impact associated with the MFC

Submitted by:	mlaier [1]
MFC after:	1 week

This is a RELENG_6 candidate
2006-09-12 04:25:13 +00:00
Robert Watson
198e7d90f9 Add struct msg to the forwarded declared data structures in mac_policy.h.
Obtained from:	TrustedBSD Project
2006-09-09 16:35:44 +00:00
Robert Watson
14f212e215 Make mpo_associate_nfsd_label() return void, not int, to match
mac_associate_nfsd_label().

Head nod:	csjp
2006-08-06 16:56:15 +00:00
Poul-Henning Kamp
9c499ad92f Remove the NDEVFSINO and NDEVFSOVERFLOW options which no longer exists in
DEVFS.

Remove the opt_devfs.h file now that it is empty.
2006-07-17 09:07:02 +00:00
Robert Watson
1d82b39143 Reconstitute struct mac_policy_ops by breaking out individual function
pointer prototypes from it into their own typedefs.  No functional or
ABI change.  This allows policies to declare their own function
prototypes based on a common definition from mac_policy.h rather than
duplicating these definitions.

Obtained from:	SEDarwin, SPARTA
MFC after:	1 month
2006-04-26 14:18:55 +00:00
Christian S.J. Peron
7935d5382b Introduce a new MAC entry point for label initialization of the NFS daemon's
credential: mac_associate_nfsd_label()

This entry point can be utilized by various Mandatory Access Control policies
so they can properly initialize the label of files which get created
as a result of an NFS operation. This work will be useful for fixing kernel
panics associated with accessing un-initialized or invalid vnode labels.

The implementation of these entry points will come shortly.

Obtained from:	TrustedBSD
Requested by:	mdodd
MFC after:	3 weeks
2006-04-06 23:33:11 +00:00
Tor Egge
d50ef66d03 Don't call vn_finished_write() if vn_start_write() failed. 2006-03-19 20:43:07 +00:00
Tor Egge
3b582b4e72 Eliminate a deadlock when creating snapshots. Blocking vn_start_write() must
be called without any vnode locks held.  Remove calls to vn_start_write() and
vn_finished_write() in vnode_pager_putpages() and add these calls before the
vnode lock is obtained to most of the callers that don't already have them.
2006-03-02 22:13:28 +00:00
Christian S.J. Peron
a5b7fde722 Lock object while we iterate through it's backing objects.
Discussed with:	alc
2005-10-09 02:37:27 +00:00
Christian S.J. Peron
7367bc5a54 Use the correct object's backing_object_offset while calculating offsets.
While we are here, add a note that we need to lock the object before walking
the backing object list.

Pointed out by:	alc
Discussed with:	rwatson
2005-10-04 14:47:47 +00:00
Christian S.J. Peron
9eea3d85cc Standard Giant push down operations for the Mandatory Access Control (MAC)
framework. This makes Giant protection around MAC operations which inter-
act with VFS conditional, based on the MPSAFE status of the file system.

Affected the following syscalls:

o __mac_get_fd
o __mac_get_file
o __mac_get_link
o __mac_set_fd
o __mac_set_file
o __mac_set_link

-Drop Giant all together in __mac_set_proc because the
 mac_cred_mmapped_drop_perms_recurse routine no longer requires it.
-Move conditional Giant aquisitions to after label allocation routines.
-Move the conditional release of Giant to before label de-allocation
 routines.

Discussed with:	rwatson
2005-10-04 14:32:58 +00:00
Christian S.J. Peron
dc063b81ab Conditionally pickup Giant in mac_cred_mmapped_drop_perms_recurse so
we can drop it all together in __mac_set_proc.

Reviewed by:	alc
Discussed with:	rwatson
2005-10-04 14:32:15 +00:00
Robert Watson
5bb52dc4d5 Complete removal of mac_create_root_mount/mpo_create_root_mount MAC
interfaces.

Obtained from:	TrustedBSD Project
Submitted by:	Chris Vance <Christopher dot Vance at SPARTA dot com>
MFC after:	3 days
2005-10-02 09:53:00 +00:00
Robert Watson
223aaaecb0 Remove mac_create_root_mount() and mpo_create_root_mount(), which
provided access to the root file system before the start of the
init process.  This was used briefly by SEBSD before it knew about
preloading data in the loader, and using that method to gain
access to data earlier results in fewer inconsistencies in the
approach.  Policy modules still have access to the root file system
creation event through the mac_create_mount() entry point.

Removed now, and will be removed from RELENG_6, in order to gain
third party policy dependencies on the entry point for the lifetime
of the 6.x branch.

MFC after:	3 days
Submitted by:	Chris Vance <Christopher dot Vance at SPARTA dot com>
Sponsored by:	SPARTA
2005-09-19 13:59:57 +00:00
Robert Watson
189c6d1a2b Insert a series of place-holder function pointers in mac_policy.h for
entry points that will be inserted over the life-time of the 6.x branch,
including for:

- New struct file labeling (void * already added to struct file), events,
  access control checks.
- Additional struct mount access control checks, internalization/
  externalization.
- mac_check_cap()
- System call enter/exit check and event.
- Socket and vnode ioctl entry points.

MFC after:	3 days
2005-08-08 16:09:33 +00:00
Robert Watson
49bb6870cc Bump the module versions of the MAC Framework and MAC policy modules
from 2 (6.x) to 3 (7.x) to allow for future changes in the MAC policy
module ABI in 7.x.

Obtained from:	TrustedBSD Project
2005-07-14 10:46:03 +00:00
Robert Watson
d26dd2d99e When devfs cloning takes place, provide access to the credential of the
process that caused the clone event to take place for the device driver
creating the device.  This allows cloned device drivers to adapt the
device node based on security aspects of the process, such as the uid,
gid, and MAC label.

- Add a cred reference to struct cdev, so that when a device node is
  instantiated as a vnode, the cloning credential can be exposed to
  MAC.

- Add make_dev_cred(), a version of make_dev() that additionally
  accepts the credential to stick in the struct cdev.  Implement it and
  make_dev() in terms of a back-end make_dev_credv().

- Add a new event handler, dev_clone_cred, which can be registered to
  receive the credential instead of dev_clone, if desired.

- Modify the MAC entry point mac_create_devfs_device() to accept an
  optional credential pointer (may be NULL), so that MAC policies can
  inspect and act on the label or other elements of the credential
  when initializing the skeleton device protections.

- Modify tty_pty.c to register clone_dev_cred and invoke make_dev_cred(),
  so that the pty clone credential is exposed to the MAC Framework.

While currently primarily focussed on MAC policies, this change is also
a prerequisite for changes to allow ptys to be instantiated with the UID
of the process looking up the pty.  This requires further changes to the
pty driver -- in particular, to immediately recycle pty nodes on last
close so that the credential-related state can be recreated on next
lookup.

Submitted by:	Andrew Reisse <andrew.reisse@sparta.com>
Obtained from:	TrustedBSD Project
Sponsored by:	SPAWAR, SPARTA
MFC after:	1 week
MFC note:	Merge to 6.x, but not 5.x for ABI reasons
2005-07-14 10:22:09 +00:00
Robert Watson
3c308b091f Eliminate MAC entry point mac_create_mbuf_from_mbuf(), which is
redundant with respect to existing mbuf copy label routines.  Expose
a new mac_copy_mbuf() routine at the top end of the Framework and
use that; use the existing mpo_copy_mbuf_label() routine on the
bottom end.

Obtained from:	TrustedBSD Project
Sponsored by:	SPARTA, SPAWAR
Approved by:	re (scottl)
2005-07-05 23:39:51 +00:00
Robert Watson
6758f88ea4 Add MAC Framework and MAC policy entry point mac_check_socket_create(),
which is invoked from socket() and socketpair(), permitting MAC
policy modules to control the creation of sockets by domain, type, and
protocol.

Obtained from:	TrustedBSD Project
Sponsored by:	SPARTA, SPAWAR
Approved by:	re (scottl)
Requested by:	SCC
2005-07-05 22:49:10 +00:00
Christian S.J. Peron
578994bbd7 Correct grammar error in comment
MFC after:	3 days
2005-06-10 04:44:38 +00:00
Robert Watson
3831e7d7f5 Gratuitous renaming of four System V Semaphore MAC Framework entry
points to convert _sema() to _sem() for consistency purposes with
respect to the other semaphore-related entry points:

mac_init_sysv_sema() -> mac_init_sysv_sem()
mac_destroy_sysv_sem() -> mac_destroy_sysv_sem()
mac_create_sysv_sema() -> mac_create_sysv_sem()
mac_cleanup_sysv_sema() -> mac_cleanup_sysv_sem()

Congruent changes are made to the policy interface to support this.

Obtained from:	TrustedBSD Project
Sponsored by:	SPAWAR, SPARTA
2005-06-07 05:03:28 +00:00
Robert Watson
5264841183 Introduce MAC Framework and MAC Policy entry points to label and control
access to POSIX Semaphores:

mac_init_posix_sem()            Initialize label for POSIX semaphore
mac_create_posix_sem()          Create POSIX semaphore
mac_destroy_posix_sem()         Destroy POSIX semaphore
mac_check_posix_sem_destroy()   Check whether semaphore may be destroyed
mac_check_posix_sem_getvalue()  Check whether semaphore may be queried
mac_check_possix_sem_open()     Check whether semaphore may be opened
mac_check_posix_sem_post()      Check whether semaphore may be posted to
mac_check_posix_sem_unlink()    Check whether semaphore may be unlinked
mac_check_posix_sem_wait()      Check whether may wait on semaphore

Update Biba, MLS, Stub, and Test policies to implement these entry points.
For information flow policies, most semaphore operations are effectively
read/write.

Submitted by:	Dandekar Hrishikesh <rishi_dandekar at sbcglobal dot net>
Sponsored by:	DARPA, McAfee, SPARTA
Obtained from:	TrustedBSD Project
2005-05-04 10:39:15 +00:00