Fix SELinux to handle 64-bit capabilities correctly, and to catch
future extensions of capabilities beyond 64 bits to ensure that SELinux
is properly updated.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
The security_get_policycaps() functions has a couple of bugs in it and it
isn't currently used by any in-tree code, so get rid of it and all of it's
bugginess.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@localhost.localdomain>
Now that the SELinux NetLabel "base SID" is always the netmsg initial SID we
can do a big optimization - caching the SID and not just the MLS attributes.
This not only saves a lot of per-packet memory allocations and copies but it
has a nice side effect of removing a chunk of code.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch introduces a mechanism for checking when labeled IPsec or SECMARK
are in use by keeping introducing a configuration reference counter for each
subsystem. In the case of labeled IPsec, whenever a labeled SA or SPD entry
is created the labeled IPsec/XFRM reference count is increased and when the
entry is removed it is decreased. In the case of SECMARK, when a SECMARK
target is created the reference count is increased and later decreased when the
target is removed. These reference counters allow SELinux to quickly determine
if either of these subsystems are enabled.
NetLabel already has a similar mechanism which provides the netlbl_enabled()
function.
This patch also renames the selinux_relabel_packet_permission() function to
selinux_secmark_relabel_packet_permission() as the original name and
description were misleading in that they referenced a single packet label which
is not the case.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
Rework the handling of network peer labels so that the different peer labeling
subsystems work better together. This includes moving both subsystems to a
single "peer" object class which involves not only changes to the permission
checks but an improved method of consolidating multiple packet peer labels.
As part of this work the inbound packet permission check code has been heavily
modified to handle both the old and new behavior in as sane a fashion as
possible.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
Add additional Flask definitions to support the new "peer" object class and
additional permissions to the netif, node, and packet object classes. Also,
bring the kernel Flask definitions up to date with the Fedora SELinux policies
by adding the "flow_in" and "flow_out" permissions to the "packet" class.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
Add a new policy capabilities bitmap to SELinux policy version 22. This bitmap
will enable the security server to query the policy to determine which features
it supports.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch adds a SELinux IP address/node SID caching mechanism similar to the
sel_netif_*() functions. The node SID queries in the SELinux hooks files are
also modified to take advantage of this new functionality. In addition, remove
the address length information from the sk_buff parsing routines as it is
redundant since we already have the address family.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
Instead of storing the packet's network interface name store the ifindex. This
allows us to defer the need to lookup the net_device structure until the audit
record is generated meaning that in the majority of cases we never need to
bother with this at all.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
The current SELinux netif code requires the caller have a valid net_device
struct pointer to lookup network interface information. However, we don't
always have a valid net_device pointer so convert the netif code to use
the ifindex values we always have as part of the sk_buff. This patch also
removes the default message SID from the network interface record, it is
not being used and therefore is "dead code".
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
In order to do any sort of IP header inspection of incoming packets we need to
know which address family, AF_INET/AF_INET6/etc., it belongs to and since the
sk_buff structure does not store this information we need to pass along the
address family separate from the packet itself.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
Adds security_get_sb_mnt_opts, security_set_sb_mnt_opts, and
security_clont_sb_mnt_opts to the LSM and to SELinux. This will allow
filesystems to directly own and control all of their mount options if they
so choose. This interface deals only with option identifiers and strings so
it should generic enough for any LSM which may come in the future.
Filesystems which pass text mount data around in the kernel (almost all of
them) need not currently make use of this interface when dealing with
SELinux since it will still parse those strings as it always has. I assume
future LSM's would do the same. NFS is the primary FS which does not use
text mount data and thus must make use of this interface.
An LSM would need to implement these functions only if they had mount time
options, such as selinux has context= or fscontext=. If the LSM has no
mount time options they could simply not implement and let the dummy ops
take care of things.
An LSM other than SELinux would need to define new option numbers in
security.h and any FS which decides to own there own security options would
need to be patched to use this new interface for every possible LSM. This
is because it was stated to me very clearly that LSM's should not attempt to
understand FS mount data and the burdon to understand security should be in
the FS which owns the options.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen D. Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Allow policy to select, in much the same way as it selects MLS support, how
the kernel should handle access decisions which contain either unknown
classes or unknown permissions in known classes. The three choices for the
policy flags are
0 - Deny unknown security access. (default)
2 - reject loading policy if it does not contain all definitions
4 - allow unknown security access
The policy's choice is exported through 2 booleans in
selinuxfs. /selinux/deny_unknown and /selinux/reject_unknown.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
It reduces the selinux overhead on read/write by only revalidating
permissions in selinux_file_permission if the task or inode labels have
changed or the policy has changed since the open-time check. A new LSM
hook, security_dentry_open, is added to capture the necessary state at open
time to allow this optimization.
(see http://marc.info/?l=selinux&m=118972995207740&w=2)
Signed-off-by: Yuichi Nakamura<ynakam@hitachisoft.jp>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Add a new security check on mmap operations to see if the user is attempting
to mmap to low area of the address space. The amount of space protected is
indicated by the new proc tunable /proc/sys/vm/mmap_min_addr and defaults to
0, preserving existing behavior.
This patch uses a new SELinux security class "memprotect." Policy already
contains a number of allow rules like a_t self:process * (unconfined_t being
one of them) which mean that putting this check in the process class (its
best current fit) would make it useless as all user processes, which we also
want to protect against, would be allowed. By taking the memprotect name of
the new class it will also make it possible for us to move some of the other
memory protect permissions out of 'process' and into the new class next time
we bump the policy version number (which I also think is a good future idea)
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
In security_get_user_sids, move the transition permission checks
outside of the section holding the policy rdlock, and use the AVC to
perform the checks, calling cond_resched after each one. These
changes should allow preemption between the individual checks and
enable caching of the results. It may however increase the overall
time spent in the function in some cases, particularly in the cache
miss case.
The long term fix will be to take much of this logic to userspace by
exporting additional state via selinuxfs, and ultimately deprecating
and eliminating this interface from the kernel.
Tested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
The structure is as follows (relative to selinuxfs root):
/class/file/index
/class/file/perms/read
/class/file/perms/write
...
Each class is allocated 33 inodes, 1 for the class index and 32 for
permissions. Relative to SEL_CLASS_INO_OFFSET, the inode of the index file
DIV 33 is the class number. The inode of the permission file % 33 is the
index of the permission for that class.
Signed-off-by: Christopher J. PeBenito <cpebenito@tresys.com>
Signed-off-by: James Morris <jmorris@namei.org>
Add support to the SELinux security server for obtaining a list of classes,
and for obtaining a list of permissions for a specified class.
Signed-off-by: Christopher J. PeBenito <cpebenito@tresys.com>
Signed-off-by: James Morris <jmorris@namei.org>
Make the initial SID contexts accessible to userspace via selinuxfs.
An initial use of this support will be to make the unlabeled context
available to libselinux for use for invalidated userspace SIDs.
Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Remove userland security class and permission definitions from the kernel
as the kernel only needs to use and validate its own class and permission
definitions and userland definitions may change.
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
As suggested, move the security_skb_extlbl_sid() function out of the security
server and into the SELinux hooks file.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
In the beginning I named the file selinux_netlabel.h to avoid potential
namespace colisions. However, over time I have realized that there are several
other similar cases of multiple header files with the same name so I'm changing
the name to something which better fits with existing naming conventions.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
Up until this patch the functions which have provided NetLabel support to
SELinux have been integrated into the SELinux security server, which for
various reasons is not really ideal. This patch makes an effort to extract as
much of the NetLabel support from the security server as possibile and move it
into it's own file within the SELinux directory structure.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch is an incremental fix to the flow_cache_genid
patch for selinux that breaks the build of 2.6.20-rc6 when
xfrm is not configured.
Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that labeled IPsec makes use of the peer_sid field in the
sk_security_struct we can remove a lot of the special cases between labeled
IPsec and NetLabel. In addition, create a new function,
security_skb_extlbl_sid(), which we can use in several places to get the
security context of the packet's external label which allows us to further
simplify the code in a few places.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch does a lot of cleanup in the SELinux NetLabel support code. A
summary of the changes include:
* Use RCU locking for the NetLabel state variable in the skk_security_struct
instead of using the inode_security_struct mutex.
* Remove unnecessary parameters in selinux_netlbl_socket_post_create().
* Rename selinux_netlbl_sk_clone_security() to
selinux_netlbl_sk_security_clone() to better fit the other NetLabel
sk_security functions.
* Improvements to selinux_netlbl_inode_permission() to help reduce the cost of
the common case.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch implements SELinux kernel support for DCCP
(http://linux-net.osdl.org/index.php/DCCP), which is similar in
operation to TCP in terms of connected state between peers.
The SELinux support for DCCP is thus modeled on existing handling of
TCP.
A new DCCP socket class is introduced, to allow protocol
differentation. The permissions for this class inherit all of the
socket permissions, as well as the current TCP permissions (node_bind,
name_bind etc). IPv4 and IPv6 are supported, although labeled
networking is not, at this stage.
Patches for SELinux userspace are at:
http://people.redhat.com/jmorris/selinux/dccp/user/
I've performed some basic testing, and it seems to be working as
expected. Adding policy support is similar to TCP, the only real
difference being that it's a different protocol.
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix the selection of an SA for an outgoing packet to be at the same
context as the originating socket/flow. This eliminates the SELinux
policy's ability to use/sendto SAs with contexts other than the socket's.
With this patch applied, the SELinux policy will require one or more of the
following for a socket to be able to communicate with/without SAs:
1. To enable a socket to communicate without using labeled-IPSec SAs:
allow socket_t unlabeled_t:association { sendto recvfrom }
2. To enable a socket to communicate with labeled-IPSec SAs:
allow socket_t self:association { sendto };
allow socket_t peer_sa_t:association { recvfrom };
Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: James Morris <jmorris@namei.org>
Fix SO_PEERSEC for tcp sockets to return the security context of
the peer (as represented by the SA from the peer) as opposed to the
SA used by the local/source socket.
Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: James Morris <jmorris@namei.org>
Since the upstreaming of the mlsxfrm modification a few months back,
testing has resulted in the identification of the following issues/bugs that
are resolved in this patch set.
1. Fix the security context used in the IKE negotiation to be the context
of the socket as opposed to the context of the SPD rule.
2. Fix SO_PEERSEC for tcp sockets to return the security context of
the peer as opposed to the source.
3. Fix the selection of an SA for an outgoing packet to be at the same
context as the originating socket/flow.
The following would be the result of applying this patchset:
- SO_PEERSEC will now correctly return the peer's context.
- IKE deamons will receive the context of the source socket/flow
as opposed to the SPD rule's context so that the negotiated SA
will be at the same context as the source socket/flow.
- The SELinux policy will require one or more of the
following for a socket to be able to communicate with/without SAs:
1. To enable a socket to communicate without using labeled-IPSec SAs:
allow socket_t unlabeled_t:association { sendto recvfrom }
2. To enable a socket to communicate with labeled-IPSec SAs:
allow socket_t self:association { sendto };
allow socket_t peer_sa_t:association { recvfrom };
This Patch: Pass correct security context to IKE for use in negotiation
Fix the security context passed to IKE for use in negotiation to be the
context of the socket as opposed to the context of the SPD rule so that
the SA carries the label of the originating socket/flow.
Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: James Morris <jmorris@namei.org>
Moves the definition of the 3 structs containing object class and
permission definitions from avc.c to avc_ss.h so that the security
server can access them for validation on policy load. This also adds
a new struct type, defined_classes_perms_t, suitable for allowing the
security server to access these data structures from the avc.
Signed-off-by: Chad Sellers <csellers@tresys.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
This patch makes two changes to protect applications from either removing or
tampering with the CIPSOv4 IP option on a socket. The first is the requirement
that applications have the CAP_NET_RAW capability to set an IPOPT_CIPSO option
on a socket; this prevents untrusted applications from setting their own
CIPSOv4 security attributes on the packets they send. The second change is to
SELinux and it prevents applications from setting any IPv4 options when there
is an IPOPT_CIPSO option already present on the socket; this prevents
applications from removing CIPSOv4 security attributes from the packets they
send.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently when an IPSec policy rule doesn't specify a security
context, it is assumed to be "unlabeled" by SELinux, and so
the IPSec policy rule fails to match to a flow that it would
otherwise match to, unless one has explicitly added an SELinux
policy rule allowing the flow to "polmatch" to the "unlabeled"
IPSec policy rules. In the absence of such an explicitly added
SELinux policy rule, the IPSec policy rule fails to match and
so the packet(s) flow in clear text without the otherwise applicable
xfrm(s) applied.
The above SELinux behavior violates the SELinux security notion of
"deny by default" which should actually translate to "encrypt by
default" in the above case.
This was first reported by Evgeniy Polyakov and the way James Morris
was seeing the problem was when connecting via IPsec to a
confined service on an SELinux box (vsftpd), which did not have the
appropriate SELinux policy permissions to send packets via IPsec.
With this patch applied, SELinux "polmatching" of flows Vs. IPSec
policy rules will only come into play when there's a explicit context
specified for the IPSec policy rule (which also means there's corresponding
SELinux policy allowing appropriate domains/flows to polmatch to this context).
Secondly, when a security module is loaded (in this case, SELinux), the
security_xfrm_policy_lookup() hook can return errors other than access denied,
such as -EINVAL. We were not handling that correctly, and in fact
inverting the return logic and propagating a false "ok" back up to
xfrm_lookup(), which then allowed packets to pass as if they were not
associated with an xfrm policy.
The solution for this is to first ensure that errno values are
correctly propagated all the way back up through the various call chains
from security_xfrm_policy_lookup(), and handled correctly.
Then, flow_cache_lookup() is modified, so that if the policy resolver
fails (typically a permission denied via the security module), the flow
cache entry is killed rather than having a null policy assigned (which
indicates that the packet can pass freely). This also forces any future
lookups for the same flow to consult the security module (e.g. SELinux)
for current security policy (rather than, say, caching the error on the
flow cache entry).
This patch: Fix the selinux side of things.
This makes sure SELinux polmatching of flow contexts to IPSec policy
rules comes into play only when an explicit context is associated
with the IPSec policy rule.
Also, this no longer defaults the context of a socket policy to
the context of the socket since the "no explicit context" case
is now handled properly.
Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch converts the semaphore in the superblock security struct to a
mutex. No locking changes or other code changes are done.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch converts the remaining isec->sem into a mutex. Very similar
locking is provided as before only in the faster smaller mutex rather than a
semaphore. An out_unlock path is introduced rather than the conditional
unlocking found in the original code.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Introduces support for policy version 21. This version of the binary
kernel policy allows for defining range transitions on security classes
other than the process security class. As always, backwards compatibility
for older formats is retained. The security class is read in as specified
when using the new format, while the "process" security class is assumed
when using an older policy format.
Signed-off-by: Darrel Goeddel <dgoeddel@trustedcs.com>
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Enable configuration of SELinux maximum supported policy version to support
legacy userland (init) that does not gracefully handle kernels that support
newer policy versions two or more beyond the installed policy, as in FC3
and FC4.
[bunk@stusta.de: improve Kconfig help text]
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Add some missing include files to the NetLabel related header files.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Uninline the selinux_netlbl_inode_permission() at the request of
Andrew Morton.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix a problem where the NetLabel specific fields of the sk_security_struct
structure were not being initialized early enough in some cases.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add NetLabel support to the SELinux LSM and modify the
socket_post_create() LSM hook to return an error code. The most
significant part of this patch is the addition of NetLabel hooks into
the following SELinux LSM hooks:
* selinux_file_permission()
* selinux_socket_sendmsg()
* selinux_socket_post_create()
* selinux_socket_sock_rcv_skb()
* selinux_socket_getpeersec_stream()
* selinux_socket_getpeersec_dgram()
* selinux_sock_graft()
* selinux_inet_conn_request()
The basic reasoning behind this patch is that outgoing packets are
"NetLabel'd" by labeling their socket and the NetLabel security
attributes are checked via the additional hook in
selinux_socket_sock_rcv_skb(). NetLabel itself is only a labeling
mechanism, similar to filesystem extended attributes, it is up to the
SELinux enforcement mechanism to perform the actual access checks.
In addition to the changes outlined above this patch also includes
some changes to the extended bitmap (ebitmap) and multi-level security
(mls) code to import and export SELinux TE/MLS attributes into and out
of NetLabel.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The following patch will fix the build problem (encountered by Andrew
Morton) when SECURITY_NETWORK_XFRM is not enabled.
As compared to git-net-selinux_xfrm_decode_session-build-fix.patch in
-mm, this patch sets the return parameter sid to SECSID_NULL in
selinux_xfrm_decode_session() and handles this value in the caller
selinux_inet_conn_request() appropriately.
Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This defaults the label of socket-specific IPSec policies to be the
same as the socket they are set on.
Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This labels the flows that could utilize IPSec xfrms at the points the
flows are defined so that IPSec policy and SAs at the right label can
be used.
The following protos are currently not handled, but they should
continue to be able to use single-labeled IPSec like they currently
do.
ipmr
ip_gre
ipip
igmp
sit
sctp
ip6_tunnel (IPv6 over IPv6 tunnel device)
decnet
Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This implements a seemless mechanism for xfrm policy selection and
state matching based on the flow sid. This also includes the necessary
SELinux enforcement pieces.
Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds security for IP sockets at the sock level. Security at the
sock level is needed to enforce the SELinux security policy for
security associations even when a sock is orphaned (such as in the TCP
LAST_ACK state).
This will also be used to enforce SELinux controls over data arriving
at or leaving a child socket while it's still waiting to be accepted.
Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This defines a routine that combines the Type Enforcement portion of
one sid with the MLS portion from the other sid to arrive at a new
sid. This would be used to define a sid for a security association
that is to be negotiated by IKE as well as for determing the sid for
open requests and connection-oriented child sockets.
Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current approach to labeling Security Associations for SELinux
purposes uses a one-to-one mapping between xfrm policy rules and
security associations.
This doesn't address the needs of real world MLS (Multi-level System,
traditional Bell-LaPadula) environments where a single xfrm policy
rule (pertaining to a range, classified to secret for example) might
need to map to multiple Security Associations (one each for
classified, secret, top secret and all the compartments applicable to
these security levels).
This patch set addresses the above problem by allowing for the mapping
of a single xfrm policy rule to multiple security associations, with
each association used in the security context it is defined for. It
also includes the security context to be used in IKE negotiation in
the acquire messages sent to the IKE daemon so that a unique SA can be
negotiated for each unique security context. A couple of bug fixes are
also included; checks to make sure the SAs used by a packet match
policy (security context-wise) on the inbound and also that the bundle
used for the outbound matches the security context of the flow. This
patch set also makes the use of the SELinux sid in flow cache lookups
seemless by including the sid in the flow key itself. Also, open
requests as well as connection-oriented child sockets are labeled
automatically to be at the same level as the peer to allow for use of
appropriately labeled IPSec associations.
Description of changes:
A "sid" member has been added to the flow cache key resulting in the
sid being available at all needed locations and the flow cache lookups
automatically using the sid. The flow sid is derived from the socket
on the outbound and the SAs (unlabeled where an SA was not used) on
the inbound.
Outbound case:
1. Find policy for the socket.
2. OLD: Find an SA that matches the policy.
NEW: Find an SA that matches BOTH the policy and the flow/socket.
This is necessary since not every SA that matches the policy
can be used for the flow/socket. Consider policy range Secret-TS,
and SAs each for Secret and TS. We don't want a TS socket to
use the Secret SA. Hence the additional check for the SA Vs. flow/socket.
3. NEW: When looking thru bundles for a policy, make sure the
flow/socket can use the bundle. If a bundle is not found,
create one, calling for IKE if necessary. If using IKE,
include the security context in the acquire message to the IKE
daemon.
Inbound case:
1. OLD: Find policy for the socket.
NEW: Find policy for the incoming packet based on the sid of the
SA(s) it used or the unlabeled sid if no SAs were
used. (Consider a case where a socket is "authorized" for two
policies (unclassified-confidential, secret-top_secret). If the
packet has come in using a secret SA, we really ought to be
using the latter policy (secret-top_secret).)
2. OLD: BUG: No check to see if the SAs used by the packet agree with
the policy sec_ctx-wise.
(It was indicated in selinux_xfrm_sock_rcv_skb() that
this was being accomplished by
(x->id.spi == tmpl->id.spi || !tmpl->id.spi) in xfrm_state_ok,
but it turns out tmpl->id.spi
would normally be zero (unless xfrm policy rules specify one
at the template level, which they usually don't).
NEW: The socket is checked for access to the SAs used (based on the
sid of the SAs) in selinux_xfrm_sock_rcv_skb().
Forward case:
This would be Step 1 from the Inbound case, followed by Steps 2 and 3
from the Outbound case.
Outstanding items/issues:
- Timewait acknowledgements and such are generated in the
current/upstream implementation using a NULL socket resulting in the
any_socket sid (SYSTEM_HIGH) to be used. This problem is not addressed
by this patch set.
This patch: Add new flask definitions to SELinux
Adds a new avperm "polmatch" to arbitrate flow/state access to a xfrm
policy rule.
Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Stephen Smalley
Paul Moore
Eric Paris
Yuichi Nakamura
Christopher J. PeBenito
James Carter
Venkat Yekkirala
Al Viro
James Morris
Chad Sellers
Darrel Goeddel