[apple/xnu.git] / bsd / net / kpi_interfacefilter.h

/*
 * Copyright (c) 2003 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this
 * file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/*!
	@header kpi_interfacefilter.h
	This header defines an API to attach interface filters. Interface
	filters may be attached to a specific interface. The filters can
	intercept all packets in to and out of the specific interface. In
	addition, the filters may intercept interface specific events and
	ioctls.
 */

#ifndef __KPI_INTERFACEFILTER__
#define __KPI_INTERFACEFILTER__
#include <sys/kernel_types.h>
#include <net/kpi_interface.h>

struct kev_msg;

/*!
	@typedef iff_input_func
	
	@discussion iff_input_func is used to filter incoming packets. The
		interface is only valid for the duration of the filter call. If
		you need to keep a reference to the interface, be sure to call
		ifnet_reference and ifnet_release. The packets passed to the
		inbound filter are different from those passed to the outbound
		filter. Packets to the inbound filter have the frame header
		passed in separately from the rest of the packet. The outbound
		data filters is passed the whole packet including the frame
		header.
		
		The frame header usually preceeds the data in the mbuf. This
		ensures that the frame header will be a valid pointer as long as
		the mbuf is not freed. If you need to change the frame header to
		point somewhere else, the recommended method is to prepend a new
		frame header to the mbuf chain (mbuf_prepend), set the header to
		point to that data, then call mbuf_adj to move the mbuf data
		pointer back to the start of the packet payload.
	@param cookie The cookie specified when this filter was attached.
	@param interface The interface the packet was recieved on.
	@param protocol The protocol of this packet. If you specified a
		protocol when attaching your filter, the protocol will only ever
		be the protocol you specified.
	@param data The inbound packet, after the frame header as determined
		by the interface.
	@param frame_ptr A pointer to the pointer to the frame header. The
		frame header length can be found by inspecting the interface's
		frame header length (ifnet_hdrlen).
	@result Return:
		0 - The caller will continue with normal processing of the packet.
		EJUSTRETURN - The caller will stop processing the packet, the packet will not be freed.
		Anything Else - The caller will free the packet and stop processing.
*/
typedef	errno_t (*iff_input_func)(void* cookie, ifnet_t interface, protocol_family_t protocol,
								  mbuf_t *data, char **frame_ptr);

/*!
	@typedef iff_output_func
	
	@discussion iff_output_func is used to filter fully formed outbound
		packets. The interface is only valid for the duration of the
		filter call. If you need to keep a reference to the interface,
		be sure to call ifnet_reference and ifnet_release.
	@param cookie The cookie specified when this filter was attached.
	@param interface The interface the packet is being transmitted on.
	@param data The fully formed outbound packet in a chain of mbufs.
		The frame header is already included. The filter function may
		modify the packet or return a different mbuf chain.
	@result Return:
		0 - The caller will continue with normal processing of the packet.
		EJUSTRETURN - The caller will stop processing the packet, the packet will not be freed.
		Anything Else - The caller will free the packet and stop processing.
*/
typedef	errno_t (*iff_output_func)(void* cookie, ifnet_t interface, protocol_family_t protocol,
								   mbuf_t *data);

/*!
	@typedef iff_event_func
	
	@discussion iff_event_func is used to filter interface specific
		events. The interface is only valid for the duration of the
		filter call. If you need to keep a reference to the interface,
		be sure to call ifnet_reference and ifnet_release.
	@param cookie The cookie specified when this filter was attached.
	@param interface The interface the packet is being transmitted on.
	@param event_msg The kernel event, may not be changed.
*/
typedef	void (*iff_event_func)(void* cookie, ifnet_t interface, protocol_family_t protocol,
							   const struct kev_msg *event_msg);

/*!
	@typedef iff_ioctl_func
	
	@discussion iff_ioctl_func is used to filter ioctls sent to an
		interface. The interface is only valid for the duration of the
		filter call. If you need to keep a reference to the interface,
		be sure to call ifnet_reference and ifnet_release.
	@param cookie The cookie specified when this filter was attached.
	@param interface The interface the packet is being transmitted on.
	@param ioctl_cmd The ioctl command.
	@param ioctl_arg A pointer to the ioctl argument.
	@result Return:
		0 - The caller will continue with normal processing of the packet.
		EJUSTRETURN - The caller will stop processing the packet, the packet will not be freed.
		Anything Else - The caller will free the packet and stop processing.
*/
typedef	errno_t (*iff_ioctl_func)(void* cookie, ifnet_t interface, protocol_family_t protocol,
								  u_long ioctl_cmd, void* ioctl_arg);

/*!
	@typedef iff_detached_func
	
	@discussion iff_detached_func is called to notify the filter that it
		has been detached from an interface. This is the last call to
		the filter that will be made. A filter may be detached if the
		interface is detached or the detach filter function is called.
		In the case that the interface is being detached, your filter's
		event function will be called with the interface detaching event
		before the your detached function will be called.
	@param cookie The cookie specified when this filter was attached.
	@param interface The interface this filter was detached from.
*/
typedef	void (*iff_detached_func)(void* cookie, ifnet_t interface);

/*!
	@struct iff_filter
	@discussion This structure is used to define an interface filter for
		use with the iflt_attach function.
	@field iff_cookie A kext defined cookie that will be passed to all
		filter functions.
	@field iff_name A filter name used for debugging purposes.
	@field iff_protocol The protocol of the packets this filter is
		interested in. If you specify zero, packets from all protocols
		will be passed to the filter.
	@field iff_input The filter function to handle inbound packets, may
		be NULL.
	@field iff_output The filter function to handle outbound packets,
		may be NULL.
	@field iff_event The filter function to handle interface events, may
		be null.
	@field iff_ioctl The filter function to handle interface ioctls, may
		be null.
	@field iff_detached The filter function used to notify the filter that
		it has been detached.
*/

struct iff_filter {
	void*				iff_cookie;
	const char*			iff_name;
	protocol_family_t	iff_protocol;
	iff_input_func		iff_input;
	iff_output_func		iff_output;
	iff_event_func		iff_event;
	iff_ioctl_func		iff_ioctl;
	iff_detached_func	iff_detached;
};

/*!
	@function iflt_attach
	@discussion Attaches an interface filter to an interface.
	@param interface The interface the filter should be attached to.
	@param filter A structure defining the filter.
	@param filter_ref A reference to the filter used to detach.
	@result 0 on success otherwise the errno error.
 */
errno_t iflt_attach(ifnet_t interface, const struct iff_filter* filter,
				    interface_filter_t *filter_ref);

/*!
	@function iflt_detach
	@discussion Detaches an interface filter from an interface.
	@param filter_ref The reference to the filter from iflt_attach.
 */
void iflt_detach(interface_filter_t filter_ref);

#endif
Commit	Line	Data
91447636 A	1	/*
	2	* Copyright (c) 2003 Apple Computer, Inc. All rights reserved.
	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
ff6e181a A	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. Please obtain a copy of the License at
	10	* http://www.opensource.apple.com/apsl/ and read it before using this
	11	* file.
91447636	12	*
ff6e181a A	13	* The Original Code and all software distributed under the License are
ff6e181a A	14	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
91447636 A	15	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
91447636 A	16	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
ff6e181a A	17	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	18	* Please see the License for the specific language governing rights and
	19	* limitations under the License.
91447636 A	20	*
	21	* @APPLE_LICENSE_HEADER_END@
	22	*/
	23	/*!
	24	@header kpi_interfacefilter.h
	25	This header defines an API to attach interface filters. Interface
	26	filters may be attached to a specific interface. The filters can
	27	intercept all packets in to and out of the specific interface. In
	28	addition, the filters may intercept interface specific events and
	29	ioctls.
	30	*/
	31
	32	#ifndef __KPI_INTERFACEFILTER__
	33	#define __KPI_INTERFACEFILTER__
	34	#include <sys/kernel_types.h>
	35	#include <net/kpi_interface.h>
	36
	37	struct kev_msg;
	38
	39	/*!
	40	@typedef iff_input_func
	41
	42	@discussion iff_input_func is used to filter incoming packets. The
	43	interface is only valid for the duration of the filter call. If
	44	you need to keep a reference to the interface, be sure to call
	45	ifnet_reference and ifnet_release. The packets passed to the
	46	inbound filter are different from those passed to the outbound
	47	filter. Packets to the inbound filter have the frame header
	48	passed in separately from the rest of the packet. The outbound
	49	data filters is passed the whole packet including the frame
	50	header.
	51
	52	The frame header usually preceeds the data in the mbuf. This
	53	ensures that the frame header will be a valid pointer as long as
	54	the mbuf is not freed. If you need to change the frame header to
	55	point somewhere else, the recommended method is to prepend a new
	56	frame header to the mbuf chain (mbuf_prepend), set the header to
	57	point to that data, then call mbuf_adj to move the mbuf data
	58	pointer back to the start of the packet payload.
	59	@param cookie The cookie specified when this filter was attached.
	60	@param interface The interface the packet was recieved on.
	61	@param protocol The protocol of this packet. If you specified a
	62	protocol when attaching your filter, the protocol will only ever
	63	be the protocol you specified.
	64	@param data The inbound packet, after the frame header as determined
	65	by the interface.
	66	@param frame_ptr A pointer to the pointer to the frame header. The
	67	frame header length can be found by inspecting the interface's
	68	frame header length (ifnet_hdrlen).
	69	@result Return:
	70	0 - The caller will continue with normal processing of the packet.
	71	EJUSTRETURN - The caller will stop processing the packet, the packet will not be freed.
	72	Anything Else - The caller will free the packet and stop processing.
	73	*/
	74	typedef errno_t (iff_input_func)(void cookie, ifnet_t interface, protocol_family_t protocol,
	75	mbuf_t data, char *frame_ptr);
	76
	77	/*!
	78	@typedef iff_output_func
	79
	80	@discussion iff_output_func is used to filter fully formed outbound
	81	packets. The interface is only valid for the duration of the
	82	filter call. If you need to keep a reference to the interface,
	83	be sure to call ifnet_reference and ifnet_release.
84	@param cookie The cookie specified when this filter was attached.
85	@param interface The interface the packet is being transmitted on.
86	@param data The fully formed outbound packet in a chain of mbufs.
87	The frame header is already included. The filter function may
88	modify the packet or return a different mbuf chain.
89	@result Return:
90	0 - The caller will continue with normal processing of the packet.
91	EJUSTRETURN - The caller will stop processing the packet, the packet will not be freed.
92	Anything Else - The caller will free the packet and stop processing.
93	*/
94	typedef errno_t (iff_output_func)(void cookie, ifnet_t interface, protocol_family_t protocol,
95	mbuf_t *data);
96
97	/*!
98	@typedef iff_event_func
99
100	@discussion iff_event_func is used to filter interface specific
101	events. The interface is only valid for the duration of the
102	filter call. If you need to keep a reference to the interface,
103	be sure to call ifnet_reference and ifnet_release.
104	@param cookie The cookie specified when this filter was attached.
105	@param interface The interface the packet is being transmitted on.
106	@param event_msg The kernel event, may not be changed.
107	*/
108	typedef void (iff_event_func)(void cookie, ifnet_t interface, protocol_family_t protocol,
109	const struct kev_msg *event_msg);
110
111	/*!
112	@typedef iff_ioctl_func
113
114	@discussion iff_ioctl_func is used to filter ioctls sent to an
115	interface. The interface is only valid for the duration of the
116	filter call. If you need to keep a reference to the interface,
117	be sure to call ifnet_reference and ifnet_release.
118	@param cookie The cookie specified when this filter was attached.
119	@param interface The interface the packet is being transmitted on.
120	@param ioctl_cmd The ioctl command.
121	@param ioctl_arg A pointer to the ioctl argument.
122	@result Return:
123	0 - The caller will continue with normal processing of the packet.
124	EJUSTRETURN - The caller will stop processing the packet, the packet will not be freed.
125	Anything Else - The caller will free the packet and stop processing.
126	*/
127	typedef errno_t (iff_ioctl_func)(void cookie, ifnet_t interface, protocol_family_t protocol,
128	u_long ioctl_cmd, void* ioctl_arg);
129
130	/*!
131	@typedef iff_detached_func
132
133	@discussion iff_detached_func is called to notify the filter that it
134	has been detached from an interface. This is the last call to
135	the filter that will be made. A filter may be detached if the
136	interface is detached or the detach filter function is called.
137	In the case that the interface is being detached, your filter's
138	event function will be called with the interface detaching event
139	before the your detached function will be called.
140	@param cookie The cookie specified when this filter was attached.
141	@param interface The interface this filter was detached from.
142	*/
143	typedef void (iff_detached_func)(void cookie, ifnet_t interface);
144
145	/*!
146	@struct iff_filter
147	@discussion This structure is used to define an interface filter for
148	use with the iflt_attach function.
149	@field iff_cookie A kext defined cookie that will be passed to all
150	filter functions.
151	@field iff_name A filter name used for debugging purposes.
152	@field iff_protocol The protocol of the packets this filter is
153	interested in. If you specify zero, packets from all protocols
154	will be passed to the filter.
155	@field iff_input The filter function to handle inbound packets, may
156	be NULL.
157	@field iff_output The filter function to handle outbound packets,
158	may be NULL.
159	@field iff_event The filter function to handle interface events, may
160	be null.
161	@field iff_ioctl The filter function to handle interface ioctls, may
162	be null.
163	@field iff_detached The filter function used to notify the filter that
164	it has been detached.
165	*/
166
167	struct iff_filter {
168	void* iff_cookie;
169	const char* iff_name;
170	protocol_family_t iff_protocol;
171	iff_input_func iff_input;
172	iff_output_func iff_output;
173	iff_event_func iff_event;
174	iff_ioctl_func iff_ioctl;
175	iff_detached_func iff_detached;
176	};
177
178	/*!
179	@function iflt_attach
180	@discussion Attaches an interface filter to an interface.
181	@param interface The interface the filter should be attached to.
182	@param filter A structure defining the filter.
183	@param filter_ref A reference to the filter used to detach.
184	@result 0 on success otherwise the errno error.
185	*/
186	errno_t iflt_attach(ifnet_t interface, const struct iff_filter* filter,
187	interface_filter_t *filter_ref);
188
189	/*!
190	@function iflt_detach
191	@discussion Detaches an interface filter from an interface.
192	@param filter_ref The reference to the filter from iflt_attach.
193	*/
194	void iflt_detach(interface_filter_t filter_ref);
195
196	#endif