on all label parsing occuring in userland, and knowledge of the loaded
policies in the user libraries. This revision of the API pushes that
parsing into the kernel, avoiding the need for shared library support
of policies in userland, permitting statically linked binaries (such
as ls, ps, and ifconfig) to use MAC labels. In these API revisions,
high level parsing of the MAC label is done in the MAC Framework,
and interpretation of label elements is delegated to the MAC policy
modules. This permits modules to export zero or more label elements
to user space if desired, and support them in the manner they want
and with the semantics they want. This is believed to be the final
revision of this interface: from the perspective of user applications,
the API has actually not changed, although the ABI has.
Approved by: re
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
Various cleanups, no functional changes:
- Fix a type in an entry point stub, socket checks accept
sockets, not vnodes.
- Trailing whitespace
- Entry point sort order
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
copy elements of one Biba or MLS label to another based on the flags
on the source label element. Use this instead of
mac_{biba,mls}_{single,range}() to simplify the existing code, as
well as support partial label updates (we don't update if none is
requested).
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
policies remains the same: subjects and objects are labeled for
integrity or sensitivity, and a dominance operator determines whether
or not subject/object accesses are permitted to limit inappropriate
information flow. Compartments are a non-hierarchal component to
the label, so add a bitfield to the label element for each, and a
set check as part of the dominance operator. This permits the
implementation of "need to know" elements of MLS.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
range on them, leaving process credentials as the only kernel
objects with label ranges in the Biba and MLS policies. We
weren't using the range in any access control decisions, so this
lets us garbage collect effectively unused code.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
collapse the two cases more cleanly: rather than wrapping an access
check around open, simply provide the open implementation for the
access vector entry. No functional change.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
we just break out some of the tests better. Minor change in that
we now better support incremental update of labels.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
instead of the default biba/high, mls/low, making it easier to use
ptys with these policies. This isn't the final solution, but does
help.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
compile fail. MAC_MAX_POLICIES should always be defined, or we have
bigger problems at hand.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
unregister. Under some obscure (perhaps demented) circumstances,
this can result in a panic if a policy is unregistered, and then someone
foolishly unregisters it again.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
that use it. Specifically, vop_stdlock uses the lock pointed to by
vp->v_vnlock. By default, getnewvnode sets up vp->v_vnlock to
reference vp->v_lock. Filesystems that wish to use the default
do not need to allocate a lock at the front of their node structure
(as some still did) or do a lockinit. They can simply start using
vn_lock/VOP_UNLOCK. Filesystems that wish to manage their own locks,
but still use the vop_stdlock functions (such as nullfs) can simply
replace vp->v_vnlock with a pointer to the lock that they wish to
have used for the vnode. Such filesystems are responsible for
setting the vp->v_vnlock back to the default in their vop_reclaim
routine (e.g., vp->v_vnlock = &vp->v_lock).
In theory, this set of changes cleans up the existing filesystem
lock interface and should have no function change to the existing
locking scheme.
Sponsored by: DARPA & NAI Labs.
checks from the MAC tree: allow policies to perform access control
for the ability of a process to send and receive data via a socket.
At some point, we might also pass in additional address information
if an explicit address is requested on send.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
seperate entry points for each occasion:
mac_check_vnode_mmap() Check at initial mapping
mac_check_vnode_mprotect() Check at mapping protection change
mac_check_vnode_mmap_downgrade() Determine if a mapping downgrade
should take place following
subject relabel.
Implement mmap() and mprotect() entry points for labeled vnode
policies. These entry points are currently not hooked up to the
VM system in the base tree. These changes improve the consistency
of the access control interface and offer more flexibility regarding
limiting access to vnode mmaping.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
flags so that we can call malloc with M_NOWAIT if necessary, avoiding
potential sleeps while holding mutexes in the TCP syncache code.
Similar to the existing support for mbuf label allocation: if we can't
allocate all the necessary label store in each policy, we back out
the label allocation and fail the socket creation. Sync from MAC tree.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
devfs VOP symlink creation by introducing a new entry point to determine
the label of the devfs_dirent prior to allocation of a vnode for the
symlink.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
point that instruments the creation of hard links. Policy implementations
to follow.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
to mbuf label initialization, that functionality was never merged to
the main tree. Go ahead and merge that functionality now. Note that
this requires policy modules to accept the case where the label
element may be destroyed even if init has not succeeded on it (in
the event that policy failed the init). This will shortly also
apply to sockets.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
order used in mac_policy.h and elsewhere. Sort order is basically
"by operation category", then "alphabetically by object". Sync to
MAC tree.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
externalization, and cred label life cycle events to entirely above
devfs and vnode events. Sync from MAC tree.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
entry points to better match the entry point ordering in mac_policy.h.
Big diff, no functional change; merge from the MAC tree.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
- If a policy isn't registered when a policy module unloads, silently
succeed.
- Hold the policy list lock across more of the validity tests to avoid
races.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
- Change mpo_init_foo(obj, label) and mpo_destroy_foo(obj, label) policy
entry points to mpo_init_foo_label(label) and
mpo_destroy_foo_label(label). This will permit the use of the same
entry points for holding temporary type-specific label during
internalization and externalization, as well as for caching purposes.
- Because of this, break out mpo_{init,destroy}_socket() and
mpo_{init,destroy}_mount() into seperate entry points for socket
main/peer labels and mount main/fs labels.
- Since the prototype for label initialization is the same across almost
all entry points, implement these entry points using common
implementations for Biba, MLS, and Test, reducing the number of
almost identical looking functions.
This simplifies policy implementation, as well as preparing us for the
merge of the new flexible userland API for managing labels on objects.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
modules to perform MAC-related events when a thread returns to user
space. This is required for policies that have floating process labels,
as it's not always possible to acquire the process lock at arbitrary
points in the stack during system call processing; process labels might
represent traditional authentication data, process history information,
or other data.
LOMAC will use this entry point to perform the process label update
prior to the thread returning to userspace, when plugged into the MAC
framework.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
(1) Where previously the pipe mutex was selectively grabbed during
pipe_ioctl(), now always grab it and then release if if not
needed. This protects the call to mac_check_pipe_ioctl() to
make sure the label remains consistent. (Note: it looks
like sigio locking may be incorrect for fgetown() since we
call it not-by-reference and sigio locking assumes call by
reference).
(2) In pipe_stat(), lock the pipe if MAC is compiled in so that
the call to mac_check_pipe_stat() gets a locked pipe to
protect label consistency. We still release the lock before
returning actual stat() data, risking inconsistency, but
apparently our pipe locking model accepts that risk.
(3) In various pipe MAC authorization checks, assert that the pipe
lock is held.
(4) Grab the lock when performing a pipe relabel operation, and
assert it a little deeper in the stack.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
TrustedBSD MAC Perforce tree. Remove unused functions
mac_biba_equal_range and mac_mls_equal_range, which determined if the
ranges in two range-enabled labels were equal.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
use the notion that a subject range of (low-high) connotes Biba
privilege rather than a single of high.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
module and is not linked into the base system, two KASSERT's rotted.
Fix them by fixing variable names. It would be really nice if
opt_global.h was used when building modules as part of a buildkernel.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, Network Associates Laboratories
v_tag is now const char * and should only be used for debugging.
Additionally:
1. All users of VT_NTS now check vfsconf->vf_type VFCF_NETWORK
2. The user of VT_PROCFS now checks for the new flag VV_PROCDEP, which
is propagated by pseudofs to all child vnodes if the fs sets PFS_PROCDEP.
Suggested by: phk
Reviewed by: bde, rwatson (earlier version)
layers deep in <sys/proc.h> or <sys/vnode.h>.
Removed unused includes.
Fixed some printf format errors (1 fatal on i386's; 1 fatal on alphas;
1 not fatal on any supported machine).
proc locking when revoking access to mmaps. Instead, perform this
later once we've changed the process label (hold onto a reference
to the new cred so that we don't lose it when we release the
process lock if another thread changes the credential).
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
for mac_check_vnode_{poll,read,stat,write}(). Pass in fp->f_cred
when calling these checks with a struct file available. Otherwise,
pass NOCRED. All currently MAC policies use active_cred, but
could now offer the cached credential semantic used for the base
system security model.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
can offer new services without reserving system call numbers, or
augmented versions of existing services. User code requests a
target policy by name, and specifies the policy-specific API plus
target. This is required in particular for our port of SELinux/FLASK
to the MAC framework since it offers additional security services.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
mac_check_pipe_poll(), mac_check_pipe_read(), mac_check_pipe_stat(),
and mac_check_pipe_write(). This is improves consistency with other
access control entry points and permits security modules to only
control the object methods that they are interested in, avoiding
switch statements.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
mac_check_vnode_poll(), mac_check_vnode_read(), mac_check_vnode_write().
This improves the consistency with other existing vnode checks, and
allows policies to avoid implementing switch statements to determine
what operations they do and do not want to authorize.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
we can check and use it later on.
Change the pieces of code which relied on mount->mnt_stat.f_owner
to check which user mounted the filesystem.
This became needed as the EA code needs to be able to allocate
blocks for "system" EA users like ACLs.
There seems to be some half-baked (probably only quarter- actually)
notion that the superuser for a given filesystem is the user who
mounted it, but this has far from been carried through. It is
unclear if it should be.
Sponsored by: DARPA & NAI Labs.
can avoid the cost of a large number of atomic operations if we're not
interested in the object count statistics.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
we can use the names _receive() and _send() for the receive() and send()
checks. Rename related constants, policy implementations, etc.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
we can use the names _receive() and _send() for the receive() and send()
checks. Rename related constants, policy implementations, etc.
PR:
Submitted by:
Reviewed by:
Approved by:
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
MFC after:
during a label change resulting in an mmap removal. This is "fail stop"
behavior, which is preferred, although it offers slightly less
transparency.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
us to reduce namespace pollution by doing a nested include of _label.h
rather than mac.h. mac.h contains lots of baggage, whereas _label.h
contains much less. A follow-up sweep to change nested inclusion will
follow. The problem regarding exporting 'struct label' to userland
due to excessive exporting of kernel structures to userland still
needs to be resolved.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
Suggested by: bde
enabled and the kernel provides the MAC registration and entry point
service. Declare a dependency on that module service for any
MAC module registered using mac_policy.h. For now, hard code the
version as 1, but once we've come up with a versioning policy, we'll
move to a #define of some sort. In the mean time, this will prevent
loading a MAC module when 'options MAC' isn't present, which (due to
a bug in the kernel linker) can result if the MAC module is preloaded
via loader.conf.
This particular evil recommended by: peter
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI LAbs
- v_vflag is protected by the vnode lock and is used when synchronization
with VOP calls is needed.
- v_iflag is protected by interlock and is used for dealing with vnode
management issues. These flags include X/O LOCK, FREE, DOOMED, etc.
- All accesses to v_iflag and v_vflag have either been locked or marked with
mp_fixme's.
- Many ASSERT_VOP_LOCKED calls have been added where the locking was not
clear.
- Many functions in vfs_subr.c were restructured to provide for stronger
locking.
Idea stolen from: BSD/OS
structure. This prevents a boatload of warnings in the MAC modules,
so we can hook them up to the build.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
kernel access control.
Provide implementations of some sample operating system security
policy extensions. These are not yet hooked up to the build as
other infrastructure is still being committed. Most of these
work fairly well and are in daily use in our development and (limited)
production environments. Some are not yet in their final form,
and a number of the labeled policies waste a lot of kernel memory
and will be fixed over the next month or so to be more conservative.
They do give good examples of the flexibility of the MAC framework
for implementing a variety of security policies.
mac_biba: Implementation of fixed-label Biba integrity policy,
similar to those found in a number of commercial
trusted operating systems. All subjects and objects
are assigned integrity levels, and information flow
is controlled based on a read-up, write-down
policy. Currently, purely hierarchal.
mac_bsdextended: Implementation of a "file system firewall",
which allows the administrator to specify a series
of rules limiting access by users and groups to
objects owned by other users and groups. This
policy is unlabeled, relying on existing system
security labeling (file permissions/ownership,
process credentials).
mac_ifoff: Secure interface silencing. Special-purpose module
to limit inappropriate out-going network traffic
for silent monitoring scenarios. Prevents the
various network stacks from generating any output
despite an interface being live for reception.
mac_mls: Implementation of fixed-label Multi-Level Security
confidentiality policy, similar to those found in
a number of commercial trusted operating systems.
All subjects and objects are assigned confidentiality
levels, and information flow is controlled based on
a write-up, read-down policy. Currently, purely
hiearchal, although non-hierarchal support is in the
works.
mac_none: Policy module implementing all MAC policy entry
points with empty stubs. A good place to start if
you want all the prototypes types in for you, and
don't mind a bit of pruning. Can be loaded, but
has no access control impact. Useful also for
performance measurements.
mac_seeotheruids: Policy module implementing a security service
similar to security.bsd.seeotheruids, only a slightly
more detailed policy involving exceptions for members
of specific groups, etc. This policy is unlabeled,
relying on existing system security labeling
(process credentials).
mac_test: Policy module implementing basic sanity tests for
label handling. Attempts to ensure that labels are
not freed multiple times, etc, etc.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
the number of policy slots to 4.
(Having run a quick errand, time to start on phase 2 of the MAC
integration)
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
kernel access control. The MAC framework permits loadable kernel
modules to link to the kernel at compile-time, boot-time, or run-time,
and augment the system security policy. This commit includes the
initial kernel implementation, although the interface with the userland
components of the oeprating system is still under work, and not all
kernel subsystems are supported. Later in this commit sequence,
documentation of which kernel subsystems will not work correctly with
a kernel compiled with MAC support will be added.
kern_mac.c contains the body of the MAC framework. Kernel and
user APIs defined in mac.h are implemented here, providing a front end
to loaded security modules. This code implements a module registration
service, state (label) management, security configuration and policy
composition.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
kernel access control. The MAC framework permits loadable kernel
modules to link to the kernel at compile-time, boot-time, or run-time,
and augment the system security policy. This commit includes the
initial kernel implementation, although the interface with the userland
components of the oeprating system is still under work, and not all
kernel subsystems are supported. Later in this commit sequence,
documentation of which kernel subsystems will not work correctly with
a kernel compiled with MAC support will be added.
Include files to declare MAC userland interface (mac.h), MAC subsystem
entry points (mac.h), and MAC policy entry points (mac_policy.h). These
files define the interface between the kernel and the MAC framework,
and between the MAC framework and each registered policy module. These
APIs and ABIs may not be assumed to be stable until following FreeBSD
5.1-RELEASE.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
o Add a mutex (sb_mtx) to struct sockbuf. This protects the data in a
socket buffer. The mutex in the receive buffer also protects the data
in struct socket.
o Determine the lock strategy for each members in struct socket.
o Lock down the following members:
- so_count
- so_options
- so_linger
- so_state
o Remove *_locked() socket APIs. Make the following socket APIs
touching the members above now require a locked socket:
- sodisconnect()
- soisconnected()
- soisconnecting()
- soisdisconnected()
- soisdisconnecting()
- sofree()
- soref()
- sorele()
- sorwakeup()
- sotryfree()
- sowakeup()
- sowwakeup()
Reviewed by: alfred
pointer instead of a proc pointer and require the process pointed to
by the second argument to be locked. We now use the thread ucred reference
for the credential checks in p_can*() as a result. p_canfoo() should now
no longer need Giant.
general cleanup of the API. The entire API now consists of two functions
similar to the pre-KSE API. The suser() function takes a thread pointer
as its only argument. The td_ucred member of this thread must be valid
so the only valid thread pointers are curthread and a few kernel threads
such as thread0. The suser_cred() function takes a pointer to a struct
ucred as its first argument and an integer flag as its second argument.
The flag is currently only used for the PRISON_ROOT flag.
Discussed on: smp@
spares (the size of the field was changed from u_short to u_int to
reflect what it really ends up being). Accordingly, change users of
xucred to set and check this field as appropriate. In the kernel,
this is being done inside the new cru2x() routine which takes a
`struct ucred' and fills out a `struct xucred' according to the
former. This also has the pleasant sideaffect of removing some
duplicate code.
Reviewed by: rwatson
o Modify the system call syntax for extattr_{get,set}_{fd,file}() so
as not to use the scatter gather API (which appeared not to be used
by any consumers, and be less portable), rather, accepts 'data'
and 'nbytes' in the style of other simple read/write interfaces.
This changes the API and ABI.
o Modify system call semantics so that extattr_get_{fd,file}() return
a size_t. When performing a read, the number of bytes read will
be returned, unless the data pointer is NULL, in which case the
number of bytes of data are returned. This changes the API only.
o Modify the VOP_GETEXTATTR() vnode operation to accept a *size_t
argument so as to return the size, if desirable. If set to NULL,
the size will not be returned.
o Update various filesystems (pseodofs, ufs) to DTRT.
These changes should make extended attributes more useful and more
portable. More commits to rebuild the system call files, as well
as update userland utilities to follow.
Obtained from: TrustedBSD Project
Sponsored by: DARPA, NAI Labs
this is a low-functionality change that changes the kernel to access the main
thread of a process via the linked list of threads rather than
assuming that it is embedded in the process. It IS still embeded there
but remove all teh code that assumes that in preparation for the next commit
which will actually move it out.
Reviewed by: peter@freebsd.org, gallatin@cs.duke.edu, benno rice,
