Most trusted OSs, with the exception of Linux, have the ability to specify
static security labels for unlabeled networks. This patch adds this ability to
the NetLabel packet labeling framework.
If the NetLabel subsystem is called to determine the security attributes of an
incoming packet it first checks to see if any recognized NetLabel packet
labeling protocols are in-use on the packet. If none can be found then the
unlabled connection table is queried and based on the packets incoming
interface and address it is matched with a security label as configured by the
administrator using the netlabel_tools package. The matching security label is
returned to the caller just as if the packet was explicitly labeled using a
labeling protocol.
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>
This patch removes some unneeded RCU read locks as we can treat the reads as
"safe" even without RCU. It also converts the NetLabel configuration refcount
from a spinlock protected u32 into atomic_t to be more consistent with the rest
of the kernel.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
Create a new NetLabel KAPI interface, netlbl_enabled(), which reports on the
current runtime status of NetLabel based on the existing configuration. LSMs
that make use of NetLabel, i.e. SELinux, can use this new function to determine
if they should perform NetLabel access checks. This patch changes the
NetLabel/SELinux glue code such that SELinux only enforces NetLabel related
access checks when netlbl_enabled() returns true.
At present NetLabel is considered to be enabled when there is at least one
labeled protocol configuration present. The result is that by default NetLabel
is considered to be disabled, however, as soon as an administrator configured
a CIPSO DOI definition NetLabel is enabled and SELinux starts enforcing
NetLabel related access controls - including unlabeled packet controls.
This patch also tries to consolidate the multiple "#ifdef CONFIG_NETLABEL"
blocks into a single block to ease future review as recommended by Linus.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
The current NetLabel code has some redundant APIs which allow both
"struct socket" and "struct sock" types to be used; this may have made
sense at some point but it is wasteful now. Remove the functions that
operate on sockets and convert the callers. Not only does this make
the code smaller and more consistent but it pushes the locking burden
up to the caller which can be more intelligent about the locks. Also,
perform the same conversion (socket to sock) on the SELinux/NetLabel
glue code where it make sense.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
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>
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>
Right now the NetLabel code always jumps into the CIPSOv4 layer to determine if
a CIPSO IP option is present. However, we can do this check directly in the
NetLabel code by making use of the CIPSO_V4_OPTEXIST() macro which should save
us a function call in the common case of not having a CIPSOv4 option present.
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>
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>
Fix a problem where NetLabel would always set the value of
sk_security_struct->peer_sid in selinux_netlbl_sock_graft() to the context of
the socket, causing problems when users would query the context of the
connection. This patch fixes this so that the value in
sk_security_struct->peer_sid is only set when the connection is NetLabel based,
otherwise the value is untouched.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a new kernel subsystem, NetLabel, to provide explicit packet
labeling services (CIPSO, RIPSO, etc.) to LSM developers. NetLabel is
designed to work in conjunction with a LSM to intercept and decode
security labels on incoming network packets as well as ensure that
outgoing network packets are labeled according to the security
mechanism employed by the LSM. The NetLabel subsystem is configured
through a Generic NETLINK interface described in the header files
included in this patch.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
