Add XEN_DOMCTL_set_max_evtchn which may be used during domain creation to
set the maximum event channel port a domain may use. This may be used to
limit the amount of Xen resources (global mapping space and xenheap) that
a domain may use for event channels.
A domain that does not have a limit set may use all the event channels
supported by the event channel ABI in use.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Acked-by: Keir Fraser <keir@xen.org>
30.07.2013 13:51, Ian Campbell wrote:
> I think it would be a bit less surprising for drive by patchers etc to
> remove the DESTDIR from POLICY_LOADPATH and add it to the install
> target, which is the usual way to do things. Up to you/Vadim though.
Signed-off-by: Vadim A. Misbakh-Soloviov <mva@mva.name>
Acked-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
This fixes framebuffer support for device model stubdoms after 3f28d007
which added the target_hack permission but did not allow the permission
to the stubdom it was created for.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Adds XSM hooks for the recently introduced XENMEM_claim_pages and
XENMEM_get_outstanding_pages operations, and adds FLASK access vectors
for them. This makes the access control decisions for these operations
match those in the rest of the hypervisor.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Acked-by: George Dunlap <george.dunlap@eu.citrix.com> (for 4.3 release)
Acked-by: Keir Fraser <keir@xen.org>
This adds an XSM hook for enabling nested HVM support, replacing an
IS_PRIV check. This hook is a partial duplicate with the xsm_hvm_param
hook, but using the existing hook would require adding the index to the
hook and would require the use of a custom hook for the xsm-disabled
case (using XSM_OTHER, which is less immediately readable) - whereas
adding a new hook retains the clarity of the existing code.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Acked-by: George Dunlap <george.dunlap@eu.citrix.com> (release perspective)
Make it possible to pass the node-affinity of a domain to the hypervisor
from the upper layers, instead of always being computed automatically.
Note that this also required generalizing the Flask hooks for setting
and getting the affinity, so that they now deal with both vcpu and
node affinity.
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Acked-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Acked-by: George Dunlap <george.dunlap@eu.citrix.com>
Acked-by: Juergen Gross <juergen.gross@ts.fujitsu.com>
Acked-by: Keir Fraser <keir@xen.org>
This adds the ability to define security classes and access vectors in
FLASK policy not defined by the hypervisor, for the use of stub domains
or applications without their own security policies.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
For the example policy shipped with Xen, it makes sense to allow dom0
access to all system calls so that policy does not need to be updated
for each new hypervisor or toolstack feature used.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Add getscheduler and setscheduler permissions to replace the
monolithic scheduler permission in the scheduler_op domctl and sysctl.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Committed-by: Keir Fraser <keir@xen.org>
This adds a pair of XSM hooks for tmem operations: xsm_tmem_op which
controls any use of tmem, and xsm_tmem_control which allows use of the
TMEM_CONTROL operations. By default, all domains can use tmem while
only IS_PRIV domains can use control operations.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Acked-by: Dan Magenheimer <dan.magenheimer@oracle.com>
Committed-by: Keir Fraser <keir@xen.org>
There are three callers of get_pg_owner:
* do_mmuext_op, which does not have XSM hooks on all subfunctions
* do_mmu_update, which has hooks that are inefficient
* do_update_va_mapping_otherdomain, which has a simple XSM hook
In order to preserve return values for the do_mmuext_op hypercall, an
additional XSM hook is required to check the operation even for those
subfunctions that do not use the pg_owner field. This also covers the
MMUEXT_UNPIN_TABLE operation which did previously have an XSM hook.
The XSM hooks in do_mmu_update were capable of replacing the checks in
get_pg_owner; however, the hooks are buried in the inner loop of the
function - not very good for performance when XSM is enabled and these
turn in to indirect function calls. This patch removes the PTE from
the hooks and replaces it with a bitfield describing what accesses are
being requested. The XSM hook can then be called only when additional
bits are set instead of once per iteration of the loop.
This patch results in a change in the FLASK permissions used for
mapping an MMIO page: the target for the permisison check on the
memory mapping is no longer resolved to the device-specific type, and
is instead either the domain's own type or domio_t (depending on if
the domain uses DOMID_SELF or DOMID_IO in the map
command). Device-specific access is still controlled via the "resource
use" permisison checked at domain creation (or device hotplug).
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Tim Deegan <tim@xen.org>
Committed-by: Keir Fraser <keir@xen.org>
Because the FLASK XSM module no longer checks IS_PRIV for remote
domain accesses covered by XSM permissions, domains now have the
ability to perform memory management and other functions on all
domains that have the same type. While it is possible to prevent this
by only creating one domain per type, this solution significantly
limits the flexibility of the type system.
This patch introduces a domain type transition to represent a domain
that is operating on itself. In the example policy, this is
demonstrated by creating a type with _self appended when declaring a
domain type which will be used for reflexive operations. AVCs for a
domain of type domU_t will look like the following:
scontext=system_u:system_r:domU_t
tcontext=system_u:system_r:domU_t_self
This change also allows policy to distinguish between event channels a
domain creates to itself and event channels created between domains of
the same type.
The IS_PRIV_FOR check used for device model domains is also no longer
checked by FLASK; a similar transition is performed when the target is
set and used when the device model accesses its target domain.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Committed-by: Keir Fraser <keir@xen.org>
The FLASK module was missing implementations of some hooks and did not
have access vectors defined for 10 domctls; define these now.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Committed-by: Keir Fraser <keir@xen.org>
Rather than keeping around headers that are autogenerated in order to
avoid adding build dependencies from xen/ to files in tools/, move the
relevant parts of the FLASK policy into the hypervisor tree and
generate the headers as part of the hypervisor's build.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Committed-by: Keir Fraser <keir@xen.org>
Allow a domain to be built under one security label and run using a
different label. This can be used to prevent the domain builder or
control domain from having the ability to access a guest domain's memory
via map_foreign_range except during the build process where this is
required.
Example domain configuration snippet:
seclabel='customer_1:vm_r:nomigrate_t'
init_seclabel='customer_1:vm_r:nomigrate_t_building'
Note: this does not provide complete protection from a malicious dom0;
mappings created during the build process may persist after the relabel,
and could be used to indirectly access the guest's memory. However, if
dom0 correctly unmaps the domain upon building, a the domU is protected
against dom0 becoming malicious in the future.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>
This adds the ability to change a domain's XSM label after creation.
The new label will be used for all future access checks; however,
existing event channels and memory mappings will remain valid even if
their creation would be denied by the new label.
With appropriate security policy and hooks in the domain builder, this
can be used to create domains that the domain builder does not have
access to after building. It can also be used to allow a domain to
drop privileges - for example, prior to launching a user-supplied
kernel loaded by a pv-grub stubdom.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Committed-by: Keir Fraser <keir@xen.org>
This field was only used to populate the ssid of dom0, which can be
handled explicitly in the domain creation hook. This also removes the
unnecessary permission check on the creation of dom0.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Committed-by: Keir Fraser <keir@xen.org>
The ability to declare common permission blocks shared across multiple
classes is not currently used in Xen. Currently, support for this
feature is broken in the header generation scripts, and it is not
expected that this feature will be used in the future, so remove the
dead code.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Committed-by: Keir Fraser <keir@xen.org>
This shows an example boolean (prot_doms_locked) which can be set at
runtime to prevent dom0 from mapping memory of domains of type
prot_domU_t.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Committed-by: Keir Fraser <keir@xen.org>
These examples show how to use constraints and the user field of the
security label to prevent communication between virtual machines of
different customers in a multi-tenant environment.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Committed-by: Keir Fraser <keir@xen.org>
Eliminate temporary files used in creating FLASK policy to improve
error reporting during policy build. Syntax errors now point to the
file and line number visible to the user, not the intermediate
temporary file.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Committed-by: Keir Fraser <keir@xen.org>
This patch sends global VIRQs to a domain designated as the VIRQ
handler
instead of sending all global VIRQ events to dom0. This is required in
order to run xenstored in a stubdom, because VIRQ_DOM_EXC must be sent
to xenstored for domain destruction to work properly.
This patch was inspired by the xenstored stubdomain patch series sent
to xen-devel by Alex Zeffertt in 2009.
Signed-off-by: Diego Ongaro <diego.ongaro@citrix.com>
Signed-off-by: Alex Zeffertt <alex.zeffertt@eu.citrix.com>
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Committed-by: Keir Fraser <keir@xen.org>
The updated example policy did not include rules to allow managing the
created domains (pause, unpause, destroy); allow these actions.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Committed-by: Ian Jackson <ian.jackson.citrix.com>
Rewrite the example policy to make it easier to understand and
demonstrate some of the security goals that FLASK can enforce.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Committed-by: Ian Jackson <ian.jackson.citrix.com>
Actions requiring IS_PRIV should also require some XSM access control
in order for XSM to be useful in confining multiple privileged
domains. Add XSM hooks for new hypercalls and sub-commands that are
under IS_PRIV but not currently under any access checks.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
The mmu_update hypercall can be used to manipulate the page tables of
a remote domain. Add a check for this in the XSM hook in addition to
the existing check on mapping pages of a remote domain.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
The domU SID is never used before a policy load, and so does not
belong in the initial_sids list.
The PIRQ SID is now incorrectly named; it should simply be called IRQ.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Committed-by: Keir Fraser <keir@xen.org>
The PHYSDEVOP_alloc_irq_vector hypercall is a noop, so its XSM check
is not useful. Remove it and the "event vector" FLASK permission.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Committed-by: Keir Fraser <keir@xen.org>
Version 26 of checkpolicy (shipped with Fedora 16) now requires that
roles be declared prior to setting types for a role. Add a declaration
of the system_r role to fix the build of default XSM/FLASK policy.
Signed-off-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Committed-by: Keir Fraser <keir@xen.org>
Xen try to inforce the xsm policy when a HVMOP_track_dirty_vram
is received (xen/arch/x86/hvm/hvm.c:3637). It was failing because
in flask_hvmcontext, xsm didn't have any case for this operation.
Signed-off-by: Jean Guyader <jean.guyader@eu.citrix.com>
Committed-by: Keir Fraser <keir@xen.org>
At some point, it seems that someone manually added Flask permission
definitions to one header file without updating the corresponding
policy configuration or the other related table. The end result is
that we can get uninterpretable AVC messages like this:
# xl dmesg | grep avc
(XEN) avc: denied { 0x4000000 } for domid=0
scontext=system_u:system_r:dom0_t tcontext=system_u:system_r:domU_t
tclass=domain
Fix this by updating the flask config and regenerating the headers
from it. In the future, this can be further improved by integrating
the automatic generation of the headers into the build process as is
presently done in SELinux.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
In a few places in the tree the Makefiles have constructs like this:
one_file another_file:
$(COMMAND_WHICH_GENERATES_BOTH_AT_ONCE)
This is wrong, because make will run _two copies_ of the same command
at once. This generally causes races and hard-to-reproduce build
failures.
Notably, `make -j4' at the top level will build stubdom libxc twice
simultaneously!
In this patch we replace the occurrences of this construct with the
correct idiom:
one_file: another_file
another_file:
$(COMMAND_WHICH_GENERATES_BOTH_AT_ONCE)
Signed-off-by: Ian Jackson <ian.jackson@eu.citrix.com>
Added the ability to add and delete ocontexts dynamically on a running
system. Two new commands have been added to the xsm hypercall, add
and delete ocontext. Twelve new library functions have been
implemented that use the hypercall commands to label and unlabel
pirqs, PCI devices, I/O ports and memory. The base policy has been
updated so dom0 has the ability to use the hypercall commands by
default. Items added to the list will not be present next time the
system reloads. They will need to be added to the static policy.
Signed-off-by : George Coker <gscoker@alpha.ncsc.mil>
Signed-off-by : Paul Nuzzi <pjnuzzi@tycho.ncsc.mil>
Add support for Xen ocontext records to enable device polices. The
default policy will not be changed and instructions have been added to
enable the new functionality. Examples on how to use the new policy
language have been added but commented out. The newest version of
checkpolicy (>= 2.0.20) and libsepol (>= 2.0.39) is needed in order to
compile it. Devices can be labeled and enforced using the following
new commands; pirqcon, iomemcon, ioportcon and pcidevicecon.
Signed-off-by : George Coker <gscoker@alpha.ncsc.mil>
Signed-off-by : Paul Nuzzi <pjnuzzi@tycho.ncsc.mil>
The original xen policy infrastructure was based off of an early
version of refpolicy. Because of this there was a lot of cruft that
does not apply to building a policy for xen. This patch does several
things. First it cleans up the makefile as to remove many unnecessary
build targets. Second it fixes an issue that the policy build process
wasn't handling interface files properly. Third it pulls in the MLS
suppport functions from current ref policy and makes use of
them. Finally it updates the xen policy with new rules to address
changes in xen since the policy was last worked on, and provides
several new abstractions for creating domains.
Signed-off-by: David P. Quigley <dpquigl@tycho.nsa.gov>
This is a back-port of the latest SELinux code to Xen, adjusted
for Xen coding style and interfaces. Unneeded functionality such
as most object context config data, handle_unknown, MLS field
defaulting, etc has been omitted.
Signed-off-by: Stephen D. Smalley <sds@tycho.nsa.gov>
Signed-off-by: George S. Coker, II <gscoker@alpha.ncsc.mil>
For now hardcode /etc w/o a prefix as there are hardcoded
config paths in the code which would break otherwise.
Signed-off-by: Christoph Egger <Christoph.Egger@amd.com>
This adds two more permissions to the default Flask policy to get a VM
with a network interface to work.
Signed-off-by: Stefan Berger <stefanb@us.ibm.com>
- The patch includes a policy for xen that can be booted into
enforcing mode and supports creation and management of
paravirtualized guests. The policy follows the dom0/domU usage
model, extension to other models or the addition of management or IO
permissions should be much more straightforward now. The option
flask_enforcing=1 can be passed on the xen line in grub to boot
into enforcing mode.
- The policy provides a basic policy for booting the platform and
creating a domU with the label system_u:object_r:domU_t. The policy
can be easily extended to support new types by modifying the xen.te
source file.
- The policy includes some basic macros which may be helpful in
extending the policy.
- The policy is compatible with and requires the most recent XSM
patch, xsm-flask-io-sysctl-hooks-090308.diff.
- The policy is not built as part of the make all as it requires the
SELinux policy compiler which may/may not be installed on all
systems. Users must go into the tools/flask/policy directory and
explicitly compile the policy.
Signed-off-by: George Coker <gscoker@alpha.ncsc.mil>
David Vrabel
Vadim A. Misbakh-Soloviov
Daniel De Graaf
Dario Faggioli
Keir Fraser
Jean Guyader
Keir Fraser