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>
have it return the buffer it had allocated
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Always initialize *scontext and *scontext_len in security_sid_to_context.
(via http://lkml.org/lkml/2007/2/23/135)
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Below is a patch which demotes many printk lines to KERN_DEBUG from
KERN_INFO. It should help stop the spamming of logs with messages in
which users are not interested nor is there any action that users should
take. It also promotes some KERN_INFO to KERN_ERR such as when there
are improper attempts to register/unregister security modules.
A similar patch was discussed a while back on list:
http://marc.theaimsgroup.com/?t=116656343500003&r=1&w=2
This patch addresses almost all of the issues raised. I believe the
only advice not taken was in the demoting of messages related to
undefined permissions and classes.
Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
security/selinux/hooks.c | 20 ++++++++++----------
security/selinux/ss/avtab.c | 2 +-
security/selinux/ss/policydb.c | 6 +++---
security/selinux/ss/sidtab.c | 2 +-
4 files changed, 15 insertions(+), 15 deletions(-)
Signed-off-by: James Morris <jmorris@namei.org>
Hmmm...turns out to not be quite enough, as the /proc/sys inodes aren't truly
private to the fs, so we can run into them in a variety of security hooks
beyond just the inode hooks, such as security_file_permission (when reading
and writing them via the vfs helpers), security_sb_mount (when mounting other
filesystems on directories in proc like binfmt_misc), and deeper within the
security module itself (as in flush_unauthorized_files upon inheritance across
execve). So I think we have to add an IS_PRIVATE() guard within SELinux, as
below. Note however that the use of the private flag here could be confusing,
as these inodes are _not_ private to the fs, are exposed to userspace, and
security modules must implement the sysctl hook to get any access control over
them.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
I goofed and when reenabling the fine grained selinux labels for
sysctls and forgot to add the "/sys" prefix before consulting
the policy database. When computing the same path using
proc_dir_entries we got the "/sys" for free as it was part
of the tree, but it isn't true for clt_table trees.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It isn't needed anymore, all of the users are gone, and all of the ctl_table
initializers have been converted to use explicit names of the fields they are
initializing.
[akpm@osdl.org: NTFS fix]
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After Al Viro (finally) succeeded in removing the sched.h #include in module.h
recently, it makes sense again to remove other superfluous sched.h includes.
There are quite a lot of files which include it but don't actually need
anything defined in there. Presumably these includes were once needed for
macros that used to live in sched.h, but moved to other header files in the
course of cleaning it up.
To ease the pain, this time I did not fiddle with any header files and only
removed #includes from .c-files, which tend to cause less trouble.
Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha,
arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig,
allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all
configs in arch/arm/configs on arm. I also checked that no new warnings were
introduced by the patch (actually, some warnings are removed that were emitted
by unnecessarily included header files).
Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Many struct file_operations in the kernel can be "const". Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data. In addition it'll catch accidental writes at compile time to
these shared resources.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Replace a small number of expressions with a call to the "container_of()"
macro.
Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Replace appropriate pairs of "kmem_cache_alloc()" + "memset(0)" with the
corresponding "kmem_cache_zalloc()" call.
Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Andi Kleen <ak@muc.de>
Cc: Roland McGrath <roland@redhat.com>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Greg KH <greg@kroah.com>
Acked-by: Joel Becker <Joel.Becker@oracle.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Jan Kara <jack@ucw.cz>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <jmorris@namei.org>
Cc: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.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>
Currently, old flow cache entries remain valid even after
a reload of SELinux policy.
This patch increments the flow cache generation id
on policy (re)loads so that flow cache entries are
revalidated as needed.
Thanks to Herbet Xu for pointing this out. See:
http://marc.theaimsgroup.com/?l=linux-netdev&m=116841378704536&w=2
There's also a general issue as well as a solution proposed
by David Miller for when flow_cache_genid wraps. I might be
submitting a separate patch for that later.
I request that this be applied to 2.6.20 since it's
a security relevant fix.
Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The spinlock protecting the update of the "sksec->nlbl_state" variable is not
currently softirq safe which can lead to problems. This patch fixes this by
changing the spin_{un}lock() functions into spin_{un}lock_bh() functions.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
This deletes mls_copy_context() in favor of mls_context_cpy() and
replaces mls_scopy_context() with mls_context_cpy_low().
Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
do not call a sleeping lock API in an RCU read section.
lock_sock_nested can sleep, its BH counterpart doesn't.
selinux_netlbl_inode_permission() needs to use the BH counterpart
unconditionally.
Compile tested.
From: Ingo Molnar <mingo@elte.hu>
added BH disabling, because this function can be called from non-atomic
contexts too, so a naked bh_lock_sock() would be deadlock-prone.
Boot-tested the resulting kernel.
Signed-off-by: Parag Warudkar <paragw@paragw.zapto.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Currently, each fdtable supports three dynamically-sized arrays of data: the
fdarray and two fdsets. The code allows the number of fds supported by the
fdarray (fdtable->max_fds) to differ from the number of fds supported by each
of the fdsets (fdtable->max_fdset).
In practice, it is wasteful for these two sizes to differ: whenever we hit a
limit on the smaller-capacity structure, we will reallocate the entire fdtable
and all the dynamic arrays within it, so any delta in the memory used by the
larger-capacity structure will never be touched at all.
Rather than hogging this excess, we shouldn't even allocate it in the first
place, and keep the capacities of the fdarray and the fdsets equal. This
patch removes fdtable->max_fdset. As an added bonus, most of the supporting
code becomes simpler.
Signed-off-by: Vadim Lobanov <vlobanov@speakeasy.net>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dipankar Sarma <dipankar@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Fix the locking of signal->tty.
Use ->sighand->siglock to protect ->signal->tty; this lock is already used
by most other members of ->signal/->sighand. And unless we are 'current'
or the tasklist_lock is held we need ->siglock to access ->signal anyway.
(NOTE: sys_unshare() is broken wrt ->sighand locking rules)
Note that tty_mutex is held over tty destruction, so while holding
tty_mutex any tty pointer remains valid. Otherwise the lifetime of ttys
are governed by their open file handles. This leaves some holes for tty
access from signal->tty (or any other non file related tty access).
It solves the tty SLAB scribbles we were seeing.
(NOTE: the change from group_send_sig_info to __group_send_sig_info needs to
be examined by someone familiar with the security framework, I think
it is safe given the SEND_SIG_PRIV from other __group_send_sig_info
invocations)
[schwidefsky@de.ibm.com: 3270 fix]
[akpm@osdl.org: various post-viro fixes]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Alan Cox <alan@redhat.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Roland McGrath <roland@redhat.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <jmorris@namei.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Jan Kara <jack@ucw.cz>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Replace all uses of kmem_cache_t with struct kmem_cache.
The patch was generated using the following script:
#!/bin/sh
#
# Replace one string by another in all the kernel sources.
#
set -e
for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do
quilt add $file
sed -e "1,\$s/$1/$2/g" $file >/tmp/$$
mv /tmp/$$ $file
quilt refresh
done
The script was run like this
sh replace kmem_cache_t "struct kmem_cache"
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
SLAB_KERNEL is an alias of GFP_KERNEL.
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
SLAB_ATOMIC is an alias of GFP_ATOMIC
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
We're seeing increasing namespace conflicts between the global
class_destroy() function declared in linux/device.h, and the private
function in the SELinux core code. This patch renames the SELinux
function to cls_destroy() to avoid this conflict.
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
The original NetLabel category bitmap was a straight char bitmap which worked
fine for the initial release as it only supported 240 bits due to limitations
in the CIPSO restricted bitmap tag (tag type 0x01). This patch converts that
straight char bitmap into an extensibile/sparse bitmap in order to lay the
foundation for other CIPSO tag types and protocols.
This patch also has a nice side effect in that all of the security attributes
passed by NetLabel into the LSM are now in a format which is in the host's
native byte/bit ordering which makes the LSM specific code much simpler; look
at the changes in security/selinux/ss/ebitmap.c as an example.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
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>
The existing netlbl_lsm_secattr struct required the LSM to check all of the
fields to determine if any security attributes were present resulting in a lot
of work in the common case of no attributes. This patch adds a 'flags' field
which is used to indicate which attributes are present in the structure; this
should allow the LSM to do a quick comparison to determine if the structure
holds any security attributes.
Example:
if (netlbl_lsm_secattr->flags)
/* security attributes present */
else
/* NO security attributes present */
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
RTM_GETPREFIX is completely unused and is thus removed.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
* 'for-2.6.20' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/selinux-2.6:
SELinux: validate kernel object classes and permissions
SELinux: ensure keys constant in hashtab_search
SELinux: export object class and permission definitions
SELinux: remove current object class and permission validation mechanism
This is a new object class and permission validation scheme that validates
against the defined kernel headers. This scheme allows extra classes
and permissions that do not conflict with the kernel definitions to be
added to the policy. This validation is now done for all policy loads,
not just subsequent loads after the first policy load.
The implementation walks the three structrures containing the defined
object class and permission values and ensures their values are the
same in the policy being loaded. This includes verifying the object
classes themselves, the permissions they contain, and the permissions
they inherit from commons. Classes or permissions that are present in the
kernel but missing from the policy cause a warning (printed to KERN_INFO)
to be printed, but do not stop the policy from loading, emulating current
behavior. Any other inconsistencies cause the load to fail.
Signed-off-by: Chad Sellers <csellers@tresys.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Makes the key argument passed into hashtab_search and all the functions
it calls constant. These functions include hash table function pointers
hash_value and keycmp. The only implementations of these currently
are symhash and symcmp, which do not modify the key. The key parameter
should never be changed by any of these, so it should be const. This
is necessary to allow calling these functions with keys found in kernel
object class and permission definitions.
Signed-off-by: Chad Sellers <csellers@tresys.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
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>
Removes the current SELinux object class and permission validation code,
as the current code makes it impossible to change or remove object classes
and permissions on a running system. Additionally, the current code does
not actually validate that the classes and permissions are correct, but
instead merely validates that they do not change between policy reloads.
Signed-off-by: Chad Sellers <csellers@tresys.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
The return value of dentry_open() shoud be checked by IS_ERR().
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
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>
Upon inspection it looked like the error handling for mls_export_cat() was
rather poor. This patch addresses this by NULL'ing out kfree()'d pointers
before returning and checking the return value of the function everywhere
it is called.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
This patch fixes two bugs in policydb_destroy. Two list pointers
(policydb.ocontexts[i] and policydb.genfs) were not being reset to NULL when
the lists they pointed to were being freed. This caused a problem when the
initial policy load failed, as the policydb being destroyed was not a
temporary new policydb that was thrown away, but rather was the global
(active) policydb. Consequently, later functions, particularly
sys_bind->selinux_socket_bind->security_node_sid and
do_rw_proc->selinux_sysctl->selinux_proc_get_sid->security_genfs_sid tried
to dereference memory that had previously been freed.
Signed-off-by: Chad Sellers <csellers@tresys.com>
Signed-off-by: James Morris <jmorris@namei.org>
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 changes NetLabel to use SECINITSID_UNLABLELED as it's source of
SELinux type information when generating a NetLabel context.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
Testing revealed a problem with the NetLabel cache where a cached entry could
be freed while in use by the LSM layer causing an oops and other problems.
This patch fixes that problem by introducing a reference counter to the cache
entry so that it is only freed when it is no longer in use.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
