[NetLabel]: SELinux support

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>

1 files changed, 21 insertions, 0 deletions

diff --git a/security/selinux/ss/mls.h b/security/selinux/ss/mls.h
index 90c5e88987f..df6032c6d49 100644
--- a/security/selinux/ss/mls.h
+++ b/security/selinux/ss/mls.h
@@ -10,6 +10,13 @@
  *
  * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc.
  */
+/*
+ * Updated: Hewlett-Packard <paul.moore@hp.com>
+ *
+ *      Added support to import/export the MLS label
+ *
+ * (c) Copyright Hewlett-Packard Development Company, L.P., 2006
+ */
 
 #ifndef _SS_MLS_H_
 #define _SS_MLS_H_
@@ -62,5 +69,19 @@ int mls_compute_sid(struct context *scontext,
 int mls_setup_user_range(struct context *fromcon, struct user_datum *user,
                          struct context *usercon);
 
+void mls_export_lvl(const struct context *context, u32 *low, u32 *high);
+void mls_import_lvl(struct context *context, u32 low, u32 high);
+
+int mls_export_cat(const struct context *context,
+		   unsigned char **low,
+		   size_t *low_len,
+		   unsigned char **high,
+		   size_t *high_len);
+int mls_import_cat(struct context *context,
+		   const unsigned char *low,
+		   size_t low_len,
+		   const unsigned char *high,
+		   size_t high_len);
+
 #endif	/* _SS_MLS_H */