xref: /linux/Documentation/netlabel/introduction.rst (revision 6fdcba32711044c35c0e1b094cbd8f3f0b4472c9)
1=====================
2NetLabel Introduction
3=====================
4
5Paul Moore, paul.moore@hp.com
6
7August 2, 2006
8
9Overview
10========
11
12NetLabel is a mechanism which can be used by kernel security modules to attach
13security attributes to outgoing network packets generated from user space
14applications and read security attributes from incoming network packets.  It
15is composed of three main components, the protocol engines, the communication
16layer, and the kernel security module API.
17
18Protocol Engines
19================
20
21The protocol engines are responsible for both applying and retrieving the
22network packet's security attributes.  If any translation between the network
23security attributes and those on the host are required then the protocol
24engine will handle those tasks as well.  Other kernel subsystems should
25refrain from calling the protocol engines directly, instead they should use
26the NetLabel kernel security module API described below.
27
28Detailed information about each NetLabel protocol engine can be found in this
29directory.
30
31Communication Layer
32===================
33
34The communication layer exists to allow NetLabel configuration and monitoring
35from user space.  The NetLabel communication layer uses a message based
36protocol built on top of the Generic NETLINK transport mechanism.  The exact
37formatting of these NetLabel messages as well as the Generic NETLINK family
38names can be found in the 'net/netlabel/' directory as comments in the
39header files as well as in 'include/net/netlabel.h'.
40
41Security Module API
42===================
43
44The purpose of the NetLabel security module API is to provide a protocol
45independent interface to the underlying NetLabel protocol engines.  In addition
46to protocol independence, the security module API is designed to be completely
47LSM independent which should allow multiple LSMs to leverage the same code
48base.
49
50Detailed information about the NetLabel security module API can be found in the
51'include/net/netlabel.h' header file as well as the 'lsm_interface.txt' file
52found in this directory.
53