[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;

__BEGIN_DECLS

/*!
	@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.
		
		All undefined ioctls are reserved for future use by Apple. If
		you need to communicate with your kext using an ioctl, please
		use SIOCSIFKPI and SIOCGIFKPI.
	@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 - This filter function handled the ioctl.
		EOPNOTSUPP - This filter function does not understand/did not handle this ioctl.
		EJUSTRETURN - This filter function handled the ioctl, processing should stop.
		Anything Else - Processing will stop, the error will be returned.
*/
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);

__END_DECLS
#endif
Commit	Line	Data
91447636	1	/*
5d5c5d0d A	2	* Copyright (c) 2003 Apple Computer, Inc. All rights reserved.
5d5c5d0d A	3	*
2d21ac55	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
91447636	5	*
2d21ac55 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.
8f6c56a5	14	*
2d21ac55 A	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
8f6c56a5 A	20	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
8f6c56a5 A	21	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
2d21ac55 A	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.
8f6c56a5	25	*
2d21ac55	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
2d21ac55 A	44	__BEGIN_DECLS
2d21ac55 A	45
91447636 A	46	/*!
	47	@typedef iff_input_func
	48
	49	@discussion iff_input_func is used to filter incoming packets. The
	50	interface is only valid for the duration of the filter call. If
	51	you need to keep a reference to the interface, be sure to call
	52	ifnet_reference and ifnet_release. The packets passed to the
	53	inbound filter are different from those passed to the outbound
	54	filter. Packets to the inbound filter have the frame header
	55	passed in separately from the rest of the packet. The outbound
	56	data filters is passed the whole packet including the frame
	57	header.
	58
	59	The frame header usually preceeds the data in the mbuf. This
	60	ensures that the frame header will be a valid pointer as long as
	61	the mbuf is not freed. If you need to change the frame header to
	62	point somewhere else, the recommended method is to prepend a new
	63	frame header to the mbuf chain (mbuf_prepend), set the header to
	64	point to that data, then call mbuf_adj to move the mbuf data
	65	pointer back to the start of the packet payload.
	66	@param cookie The cookie specified when this filter was attached.
	67	@param interface The interface the packet was recieved on.
	68	@param protocol The protocol of this packet. If you specified a
	69	protocol when attaching your filter, the protocol will only ever
	70	be the protocol you specified.
	71	@param data The inbound packet, after the frame header as determined
	72	by the interface.
	73	@param frame_ptr A pointer to the pointer to the frame header. The
	74	frame header length can be found by inspecting the interface's
	75	frame header length (ifnet_hdrlen).
	76	@result Return:
	77	0 - The caller will continue with normal processing of the packet.
	78	EJUSTRETURN - The caller will stop processing the packet, the packet will not be freed.
	79	Anything Else - The caller will free the packet and stop processing.
	80	*/
	81	typedef errno_t (iff_input_func)(void cookie, ifnet_t interface, protocol_family_t protocol,
	82	mbuf_t data, char *frame_ptr);
	83
	84	/*!
	85	@typedef iff_output_func
	86
	87	@discussion iff_output_func is used to filter fully formed outbound
	88	packets. The interface is only valid for the duration of the
	89	filter call. If you need to keep a reference to the interface,
	90	be sure to call ifnet_reference and ifnet_release.
	91	@param cookie The cookie specified when this filter was attached.
	92	@param interface The interface the packet is being transmitted on.
	93	@param data The fully formed outbound packet in a chain of mbufs.
	94	The frame header is already included. The filter function may
	95	modify the packet or return a different mbuf chain.
	96	@result Return:
	97	0 - The caller will continue with normal processing of the packet.
	98	EJUSTRETURN - The caller will stop processing the packet, the packet will not be freed.
	99	Anything Else - The caller will free the packet and stop processing.
	100	*/
	101	typedef errno_t (iff_output_func)(void cookie, ifnet_t interface, protocol_family_t protocol,
	102	mbuf_t *data);
	103
	104	/*!
	105	@typedef iff_event_func
	106
	107	@discussion iff_event_func is used to filter interface specific
	108	events. The interface is only valid for the duration of the
	109	filter call. If you need to keep a reference to the interface,
110	be sure to call ifnet_reference and ifnet_release.
111	@param cookie The cookie specified when this filter was attached.
112	@param interface The interface the packet is being transmitted on.
113	@param event_msg The kernel event, may not be changed.
114	*/
115	typedef void (iff_event_func)(void cookie, ifnet_t interface, protocol_family_t protocol,
116	const struct kev_msg *event_msg);
117
118	/*!
119	@typedef iff_ioctl_func
120
121	@discussion iff_ioctl_func is used to filter ioctls sent to an
122	interface. The interface is only valid for the duration of the
123	filter call. If you need to keep a reference to the interface,
124	be sure to call ifnet_reference and ifnet_release.
2d21ac55 A	125
	126	All undefined ioctls are reserved for future use by Apple. If
	127	you need to communicate with your kext using an ioctl, please
	128	use SIOCSIFKPI and SIOCGIFKPI.
91447636 A	129	@param cookie The cookie specified when this filter was attached.
	130	@param interface The interface the packet is being transmitted on.
	131	@param ioctl_cmd The ioctl command.
	132	@param ioctl_arg A pointer to the ioctl argument.
	133	@result Return:
2d21ac55 A	134	0 - This filter function handled the ioctl.
	135	EOPNOTSUPP - This filter function does not understand/did not handle this ioctl.
	136	EJUSTRETURN - This filter function handled the ioctl, processing should stop.
	137	Anything Else - Processing will stop, the error will be returned.
91447636 A	138	*/
	139	typedef errno_t (iff_ioctl_func)(void cookie, ifnet_t interface, protocol_family_t protocol,
	140	u_long ioctl_cmd, void* ioctl_arg);
	141
	142	/*!
	143	@typedef iff_detached_func
	144
	145	@discussion iff_detached_func is called to notify the filter that it
	146	has been detached from an interface. This is the last call to
	147	the filter that will be made. A filter may be detached if the
	148	interface is detached or the detach filter function is called.
	149	In the case that the interface is being detached, your filter's
	150	event function will be called with the interface detaching event
	151	before the your detached function will be called.
	152	@param cookie The cookie specified when this filter was attached.
	153	@param interface The interface this filter was detached from.
	154	*/
	155	typedef void (iff_detached_func)(void cookie, ifnet_t interface);
	156
	157	/*!
	158	@struct iff_filter
	159	@discussion This structure is used to define an interface filter for
	160	use with the iflt_attach function.
	161	@field iff_cookie A kext defined cookie that will be passed to all
	162	filter functions.
	163	@field iff_name A filter name used for debugging purposes.
	164	@field iff_protocol The protocol of the packets this filter is
	165	interested in. If you specify zero, packets from all protocols
	166	will be passed to the filter.
	167	@field iff_input The filter function to handle inbound packets, may
	168	be NULL.
	169	@field iff_output The filter function to handle outbound packets,
	170	may be NULL.
	171	@field iff_event The filter function to handle interface events, may
	172	be null.
	173	@field iff_ioctl The filter function to handle interface ioctls, may
	174	be null.
	175	@field iff_detached The filter function used to notify the filter that
	176	it has been detached.
	177	*/
	178
	179	struct iff_filter {
	180	void* iff_cookie;
	181	const char* iff_name;
	182	protocol_family_t iff_protocol;
	183	iff_input_func iff_input;
	184	iff_output_func iff_output;
	185	iff_event_func iff_event;
	186	iff_ioctl_func iff_ioctl;
	187	iff_detached_func iff_detached;
	188	};
	189
	190	/*!
	191	@function iflt_attach
	192	@discussion Attaches an interface filter to an interface.
	193	@param interface The interface the filter should be attached to.
	194	@param filter A structure defining the filter.
	195	@param filter_ref A reference to the filter used to detach.
	196	@result 0 on success otherwise the errno error.
	197	*/
	198	errno_t iflt_attach(ifnet_t interface, const struct iff_filter* filter,
	199	interface_filter_t *filter_ref);
	200
	201	/*!
202	@function iflt_detach
203	@discussion Detaches an interface filter from an interface.
204	@param filter_ref The reference to the filter from iflt_attach.
205	*/
206	void iflt_detach(interface_filter_t filter_ref);
6601e61a	207
2d21ac55 A	208	__END_DECLS
2d21ac55 A	209	#endif