1/*
2 * Copyright (c) 2008-2012 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28/*!
29	@header kpi_protocol.h
30	This header defines an API to interact with protocols in the kernel.
31	The KPIs in this header file can be used to interact with protocols
32	that already exist in the stack. These KPIs can be used to support
33	existing protocols over media types that are not natively supported
34	in the kernel, such as ATM.
35 */
36
37#ifndef __KPI_PROTOCOL__
38#define __KPI_PROTOCOL__
39#include <sys/kernel_types.h>
40#include <net/kpi_interface.h>
41
42__BEGIN_DECLS
43
44/******************************************************************************/
45/* Protocol input/inject                                                      */
46/******************************************************************************/
47
48#ifdef BSD_KERNEL_PRIVATE
49/*!
50	@typedef protocol_input_handler
51	@discussion protocol_input_handler is called to input a packet. If
52		your protocol has specified a global lock, the lock will be held
53		when this funciton is called.
54	@pararm protocol The protocol this packet is intended for.
55	@param packet The packet that should be input.
56 */
57typedef void (*proto_input_handler)(protocol_family_t protocol, mbuf_t packet);
58
59/*!
60	@typedef proto_input_detached_handler
61	@discussion proto_input_detached_handler is called to notify the
62		protocol that it has been detached. When this function is
63		called, the proto_input_handler will not be called again, making
64		it safe to unload.
65	@pararm protocol The protocol detached.
66 */
67typedef void (*proto_input_detached_handler)(protocol_family_t protocol);
68
69/*!
70	@function proto_register_input
71	@discussion Allows the caller to specify the functions called when a
72		packet for a protocol is received.
73	@param protocol The protocol family these functions will receive
74		packets for.
75	@param input The function called when a packet is input.
76	@param chains Input function supports packet chains.
77	@result A errno error on failure.
78 */
79extern errno_t proto_register_input(protocol_family_t protocol,
80    proto_input_handler input, proto_input_detached_handler detached,
81    int chains);
82
83/*!
84	@function proto_unregister_input
85	@discussion Allows the caller to unregister the input and inject
86		functions for a protocol. The input/inject functions may not be
87		unregistered immediately if there is a chance they are in use.
88		To notify the owner when the functions are no longer in use, the
89		proto_detached_handler function will be called. It is not safe
90		to unload until the proto_detached_handler is called.
91	@param protocol The protocol family these functions will receive
92		packets for.
93	@param input The function called when a packet is input.
94	@param inject The function to called when a packet is injected (not
95		on the normal input path).
96	@result A errno error on failure.
97 */
98extern void proto_unregister_input(protocol_family_t protocol);
99#endif /* BSD_KERNEL_PRIVATE */
100
101/*!
102	@function proto_input
103	@discussion Inputs a packet on the specified protocol from the input
104		path.
105	@param protocol The protocol of the packet.
106	@param packet The first packet in a chain of packets to be input.
107	@result A errno error on failure. Unless proto_input returns zero,
108		the caller is responsible for freeing the mbuf.
109 */
110extern errno_t proto_input(protocol_family_t protocol, mbuf_t packet);
111
112/*!
113	@function proto_inject
114	@discussion Injects a packet on the specified protocol from
115		anywhere. To avoid recursion, the protocol may need to queue the
116		packet to be handled later.
117	@param protocol The protocol of the packet.
118	@param packet The first packet in a chain of packets to be injected.
119	@result A errno error on failure. Unless proto_inject returns zero,
120		the caller is responsible for freeing the mbuf.
121 */
122extern errno_t proto_inject(protocol_family_t protocol, mbuf_t packet);
123
124
125/******************************************************************************/
126/* Protocol plumbing                                                          */
127/******************************************************************************/
128
129/*!
130	@typedef proto_plumb_handler
131	@discussion proto_plumb_handler is called to attach a protocol to an
132		interface. A typical protocol plumb function would fill out an
133		ifnet_attach_proto_param and call ifnet_attach_protocol.
134	@param ifp The interface the protocol should be attached to.
135	@param protocol_family The protocol that should be attached to the
136		interface.
137	@result
138		A non-zero value of the attach failed.
139 */
140typedef errno_t (*proto_plumb_handler)(ifnet_t ifp, protocol_family_t protocol);
141
142/*!
143	@typedef proto_unplumb_handler
144	@discussion proto_unplumb_handler is called to detach a protocol
145		from an interface. A typical unplumb function would call
146		ifnet_detach_protocol and perform any necessary cleanup.
147	@param ifp The interface the protocol should be detached from.
148	@param protocol_family The protocol that should be detached from the
149		interface.
150 */
151typedef void (*proto_unplumb_handler)(ifnet_t ifp, protocol_family_t protocol);
152
153/*!
154	@function proto_register_plumber
155	@discussion Allows the caller to specify the functions called when a
156		protocol is attached to an interface belonging to the specified
157		family and when that protocol is detached.
158	@param proto_fam The protocol family these plumbing functions will
159		handle.
160	@param if_fam The interface family these plumbing functions will
161		handle.
162	@param plumb The function to call to attach the protocol to an
163		interface.
164	@param unplumb The function to call to detach the protocol to an
165		interface, may be NULL in which case ifnet_detach_protocol will
166		be used to detach the protocol.
167	@result A non-zero value of the attach failed.
168 */
169extern errno_t proto_register_plumber(protocol_family_t proto_fam,
170    ifnet_family_t if_fam, proto_plumb_handler plumb,
171    proto_unplumb_handler unplumb);
172
173/*!
174	@function proto_unregister_plumber
175	@discussion Unregisters a previously registered plumbing function.
176	@param proto_fam The protocol family these plumbing functions
177		handle.
178	@param if_fam The interface family these plumbing functions handle.
179 */
180extern void proto_unregister_plumber(protocol_family_t proto_fam,
181    ifnet_family_t if_fam);
182
183#ifdef BSD_KERNEL_PRIVATE
184/*
185	@function proto_plumb
186	@discussion Plumbs a protocol to an actual interface.  This will find
187		a registered protocol module and call its attach function.
188		The module will typically call dlil_attach_protocol() with the
189		appropriate parameters.
190	@param protocol_family The protocol family.
191	@param ifp The interface to plumb the protocol to.
192	@result 0: No error.
193		ENOENT: No module was registered.
194		Other: Error returned by the attach_proto function
195*/
196extern errno_t proto_plumb(protocol_family_t protocol_family, ifnet_t ifp);
197
198/*
199	@function proto_unplumb
200	@discussion Unplumbs a protocol from an interface.  This will find
201		a registered protocol module and call its detach function.
202		The module will typically call dlil_detach_protocol() with
203		the appropriate parameters.  If no module is found, this
204		function will call dlil_detach_protocol directly().
205	@param protocol_family The protocol family.
206	@param ifp The interface to unplumb the protocol from.
207	@result 0: No error.
208		ENOENT: No module was registered.
209		Other: Error returned by the attach_proto function
210*/
211extern errno_t proto_unplumb(protocol_family_t protocol_family, ifnet_t ifp);
212
213__private_extern__ void
214proto_kpi_init(void);
215
216#endif /* BSD_KERNEL_PRIVATE */
217__END_DECLS
218
219#endif /* __KPI_PROTOCOL__ */
220