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

/*
 * Copyright (c) 2003 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_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. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 * 
 * 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_OSREFERENCE_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	1	/*
5d5c5d0d A	2	* Copyright (c) 2003 Apple Computer, Inc. All rights reserved.
5d5c5d0d A	3	*
8f6c56a5	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
91447636	5	*
8f6c56a5 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. 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
8ad349bb	24	* limitations under the License.
8f6c56a5 A	25	*
8f6c56a5 A	26	* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
91447636 A	27	*/
	28	/*!
	29	@header kpi_interfacefilter.h
	30	This header defines an API to attach interface filters. Interface
	31	filters may be attached to a specific interface. The filters can
	32	intercept all packets in to and out of the specific interface. In
	33	addition, the filters may intercept interface specific events and
	34	ioctls.
	35	*/
	36
	37	#ifndef __KPI_INTERFACEFILTER__
	38	#define __KPI_INTERFACEFILTER__
	39	#include <sys/kernel_types.h>
	40	#include <net/kpi_interface.h>
	41
	42	struct kev_msg;
	43
	44	/*!
	45	@typedef iff_input_func
	46
	47	@discussion iff_input_func is used to filter incoming packets. The
	48	interface is only valid for the duration of the filter call. If
	49	you need to keep a reference to the interface, be sure to call
	50	ifnet_reference and ifnet_release. The packets passed to the
	51	inbound filter are different from those passed to the outbound
	52	filter. Packets to the inbound filter have the frame header
	53	passed in separately from the rest of the packet. The outbound
	54	data filters is passed the whole packet including the frame
	55	header.
	56
	57	The frame header usually preceeds the data in the mbuf. This
	58	ensures that the frame header will be a valid pointer as long as
	59	the mbuf is not freed. If you need to change the frame header to
	60	point somewhere else, the recommended method is to prepend a new
	61	frame header to the mbuf chain (mbuf_prepend), set the header to
	62	point to that data, then call mbuf_adj to move the mbuf data
	63	pointer back to the start of the packet payload.
	64	@param cookie The cookie specified when this filter was attached.
	65	@param interface The interface the packet was recieved on.
	66	@param protocol The protocol of this packet. If you specified a
	67	protocol when attaching your filter, the protocol will only ever
	68	be the protocol you specified.
	69	@param data The inbound packet, after the frame header as determined
	70	by the interface.
	71	@param frame_ptr A pointer to the pointer to the frame header. The
	72	frame header length can be found by inspecting the interface's
	73	frame header length (ifnet_hdrlen).
	74	@result Return:
	75	0 - The caller will continue with normal processing of the packet.
	76	EJUSTRETURN - The caller will stop processing the packet, the packet will not be freed.
	77	Anything Else - The caller will free the packet and stop processing.
	78	*/
	79	typedef errno_t (iff_input_func)(void cookie, ifnet_t interface, protocol_family_t protocol,
	80	mbuf_t data, char *frame_ptr);
	81
	82	/*!
	83	@typedef iff_output_func
	84
	85	@discussion iff_output_func is used to filter fully formed outbound
	86	packets. The interface is only valid for the duration of the
	87	filter call. If you need to keep a reference to the interface,
	88	be sure to call ifnet_reference and ifnet_release.
	89	@param cookie The cookie specified when this filter was attached.
	90	@param interface The interface the packet is being transmitted on.
91	@param data The fully formed outbound packet in a chain of mbufs.
92	The frame header is already included. The filter function may
93	modify the packet or return a different mbuf chain.
94	@result Return:
95	0 - The caller will continue with normal processing of the packet.
96	EJUSTRETURN - The caller will stop processing the packet, the packet will not be freed.
97	Anything Else - The caller will free the packet and stop processing.
98	*/
99	typedef errno_t (iff_output_func)(void cookie, ifnet_t interface, protocol_family_t protocol,
100	mbuf_t *data);
101
102	/*!
103	@typedef iff_event_func
104
105	@discussion iff_event_func is used to filter interface specific
106	events. The interface is only valid for the duration of the
107	filter call. If you need to keep a reference to the interface,
108	be sure to call ifnet_reference and ifnet_release.
109	@param cookie The cookie specified when this filter was attached.
110	@param interface The interface the packet is being transmitted on.
111	@param event_msg The kernel event, may not be changed.
112	*/
113	typedef void (iff_event_func)(void cookie, ifnet_t interface, protocol_family_t protocol,
114	const struct kev_msg *event_msg);
115
116	/*!
117	@typedef iff_ioctl_func
118
119	@discussion iff_ioctl_func is used to filter ioctls sent to an
120	interface. The interface is only valid for the duration of the
121	filter call. If you need to keep a reference to the interface,
122	be sure to call ifnet_reference and ifnet_release.
123	@param cookie The cookie specified when this filter was attached.
124	@param interface The interface the packet is being transmitted on.
125	@param ioctl_cmd The ioctl command.
126	@param ioctl_arg A pointer to the ioctl argument.
127	@result Return:
128	0 - The caller will continue with normal processing of the packet.
129	EJUSTRETURN - The caller will stop processing the packet, the packet will not be freed.
130	Anything Else - The caller will free the packet and stop processing.
131	*/
132	typedef errno_t (iff_ioctl_func)(void cookie, ifnet_t interface, protocol_family_t protocol,
133	u_long ioctl_cmd, void* ioctl_arg);
134
135	/*!
136	@typedef iff_detached_func
137
138	@discussion iff_detached_func is called to notify the filter that it
139	has been detached from an interface. This is the last call to
140	the filter that will be made. A filter may be detached if the
141	interface is detached or the detach filter function is called.
142	In the case that the interface is being detached, your filter's
143	event function will be called with the interface detaching event
144	before the your detached function will be called.
145	@param cookie The cookie specified when this filter was attached.
146	@param interface The interface this filter was detached from.
147	*/
148	typedef void (iff_detached_func)(void cookie, ifnet_t interface);
149
150	/*!
151	@struct iff_filter
152	@discussion This structure is used to define an interface filter for
153	use with the iflt_attach function.
154	@field iff_cookie A kext defined cookie that will be passed to all
155	filter functions.
156	@field iff_name A filter name used for debugging purposes.
157	@field iff_protocol The protocol of the packets this filter is
158	interested in. If you specify zero, packets from all protocols
159	will be passed to the filter.
160	@field iff_input The filter function to handle inbound packets, may
161	be NULL.
162	@field iff_output The filter function to handle outbound packets,
163	may be NULL.
164	@field iff_event The filter function to handle interface events, may
165	be null.
166	@field iff_ioctl The filter function to handle interface ioctls, may
167	be null.
168	@field iff_detached The filter function used to notify the filter that
169	it has been detached.
170	*/
171
172	struct iff_filter {
173	void* iff_cookie;
174	const char* iff_name;
175	protocol_family_t iff_protocol;
176	iff_input_func iff_input;
177	iff_output_func iff_output;
178	iff_event_func iff_event;
179	iff_ioctl_func iff_ioctl;
180	iff_detached_func iff_detached;
181	};
182
183	/*!
184	@function iflt_attach
185	@discussion Attaches an interface filter to an interface.
186	@param interface The interface the filter should be attached to.
187	@param filter A structure defining the filter.
188	@param filter_ref A reference to the filter used to detach.
189	@result 0 on success otherwise the errno error.
190	*/
191	errno_t iflt_attach(ifnet_t interface, const struct iff_filter* filter,
192	interface_filter_t *filter_ref);
193
194	/*!
195	@function iflt_detach
196	@discussion Detaches an interface filter from an interface.
197	@param filter_ref The reference to the filter from iflt_attach.
198	*/
199	void iflt_detach(interface_filter_t filter_ref);
200
201	#endif