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: NPaul Moore <paul.moore@hp.com>
Signed-off-by: NJames 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: NPaul Moore <paul.moore@hp.com>
Signed-off-by: NJames 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: NPaul Moore <paul.moore@hp.com>
Signed-off-by: NJames 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: NPaul Moore <paul.moore@hp.com>
Signed-off-by: NJames 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: NPaul Moore <paul.moore@hp.com>
Signed-off-by: NJames 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: NPaul Moore <paul.moore@hp.com>
Signed-off-by: NJames 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: NPaul Moore <paul.moore@hp.com>
Signed-off-by: NJames 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: NPaul Moore <paul.moore@hp.com>
Signed-off-by: NJames Morris <jmorris@namei.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add some missing include files to the NetLabel related header files.
Signed-off-by: NPaul Moore <paul.moore@hp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Uninline the selinux_netlbl_inode_permission() at the request of
Andrew Morton.
Signed-off-by: NPaul Moore <paul.moore@hp.com>
Signed-off-by: NDavid 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: NPaul Moore <paul.moore@hp.com>
Signed-off-by: NDavid 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: NPaul Moore <paul.moore@hp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>