[apple/xnu.git] / bsd / netinet / kpi_ipfilter.h

/*
 * Copyright (c) 2008-2010 Apple 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_ipfilter.h
	This header defines an API to attach IP filters. IP filters may be
	attached to intercept either IPv4 or IPv6 packets. The filters can
	intercept all IP packets in to and out of the host regardless of
	interface.
 */

#ifndef __KPI_IPFILTER__
#define __KPI_IPFILTER__

#include <sys/kernel_types.h>

/*
 * ipf_pktopts
 *
 * Options for outgoing packets. The options need to be preserved when 
 * re-injecting a packet.
 */
struct ipf_pktopts {
	u_int32_t			ippo_flags;
	ifnet_t				ippo_mcast_ifnet;
	int				ippo_mcast_loop;
	u_int8_t			ippo_mcast_ttl;
};
#define IPPOF_MCAST_OPTS	0x1
#ifdef PRIVATE
#define IPPOF_BOUND_IF		0x2
#define IPPOF_NO_IFT_CELLULAR	0x4
#define IPPOF_SHIFT_IFSCOPE	16
#endif /* PRIVATE */

typedef struct ipf_pktopts *ipf_pktopts_t;

__BEGIN_DECLS

/*!
	@typedef ipf_input_func

	@discussion ipf_input_func is used to filter incoming ip packets.
		The IP filter is called for packets from all interfaces. The
		filter is called between when the general IP processing is
		handled and when the packet is passed up to the next layer
		protocol such as udp or tcp. In the case of encapsulation, such
		as UDP in ESP (IPSec), your filter will be called once for ESP
		and then again for UDP. This will give your filter an
		opportunity to process the ESP header as well as the decrypted
		packet. Offset and protocol are used to determine where in the
		packet processing is currently occuring. If you're only
		interested in TCP or UDP packets, just return 0 if protocol
		doesn't match TCP or UDP.
	@param cookie The cookie specified when your filter was attached.
	@param data The reassembled ip packet, data will start at the ip
		header.
	@param offset An offset to the next header
		(udp/tcp/icmp/esp/etc...).
	@param protocol The protocol type (udp/tcp/icmp/etc...) of the IP packet
	@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 (*ipf_input_func)(void *cookie, mbuf_t *data, int offset,
    u_int8_t protocol);

/*!
	@typedef ipf_output_func

	@discussion ipf_output_func is used to filter outbound ip packets.
		The IP filter is called for packets to all interfaces. The
		filter is called before fragmentation and IPSec processing. If
		you need to change the destination IP address, call
		ipf_inject_output and return EJUSTRETURN.
	@param cookie The cookie specified when your filter was attached.
	@param data The ip packet, will contain an IP header followed by the
		rest of the IP packet.
	@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 (*ipf_output_func)(void *cookie, mbuf_t *data,
    ipf_pktopts_t options);

/*!
	@typedef ipf_detach_func

	@discussion ipf_detach_func is called to notify your filter that it
		has been detached.
	@param cookie The cookie specified when your filter was attached.
*/
typedef	void (*ipf_detach_func)(void *cookie);

/*!
	@typedef ipf_filter
	@discussion This structure is used to define an IP filter for
		use with the ipf_addv4 or ipf_addv6 function.
	@field cookie A kext defined cookie that will be passed to all
		filter functions.
	@field name A filter name used for debugging purposes.
	@field ipf_input The filter function to handle inbound packets.
	@field ipf_output The filter function to handle outbound packets.
	@field ipf_detach The filter function to notify of a detach.
*/
struct ipf_filter {
	void		*cookie;
	const char	*name;
	ipf_input_func	ipf_input;
	ipf_output_func	ipf_output;
	ipf_detach_func	ipf_detach;
};

struct opaque_ipfilter;
typedef	struct opaque_ipfilter *ipfilter_t;

/*!
	@function ipf_addv4
	@discussion Attaches an IPv4 ip filter.
	@param filter A structure defining the filter.
	@param filter_ref A reference to the filter used to detach it.
	@result 0 on success otherwise the errno error.
 */
extern errno_t ipf_addv4(const struct ipf_filter *filter,
    ipfilter_t *filter_ref);

/*!
	@function ipf_addv6
	@discussion Attaches an IPv6 ip filter.
	@param filter A structure defining the filter.
	@param filter_ref A reference to the filter used to detach it.
	@result 0 on success otherwise the errno error.
 */
extern errno_t ipf_addv6(const struct ipf_filter *filter,
    ipfilter_t *filter_ref);

/*!
	@function ipf_remove
	@discussion Detaches an IPv4 or IPv6 filter.
	@param filter_ref The reference to the filter returned from ipf_addv4 or
		ipf_addv6.
	@result 0 on success otherwise the errno error.
 */
extern errno_t ipf_remove(ipfilter_t filter_ref);

/*!
	@function ipf_inject_input
	@discussion Inject an IP packet as though it had just been
		reassembled in ip_input. When re-injecting a packet intercepted
		by the filter's ipf_input function, an IP filter can pass its
		reference to avoid processing the packet twice. This also
		prevents ip filters installed before this filter from
		getting a chance to process the packet. If the filter modified
		the packet, it should not specify the filter ref to give other
		filters a chance to process the new packet.

		Caller is responsible for freeing mbuf chain in the event that
		ipf_inject_input returns an error.
	@param data The complete IPv4 or IPv6 packet, receive interface must
		be set.
	@param filter_ref The reference to the filter injecting the data
	@result 0 on success otherwise the errno error.
 */
extern errno_t ipf_inject_input(mbuf_t data, ipfilter_t filter_ref);

/*!
	@function ipf_inject_output
	@discussion Inject an IP packet as though it had just been sent to
		ip_output. When re-injecting a packet intercepted by the
		filter's ipf_output function, an IP filter can pass its
		reference to avoid processing the packet twice. This also
		prevents ip filters installed before this filter from getting a
		chance to process the packet. If the filter modified the packet,
		it should not specify the filter ref to give other filters a
		chance to process the new packet.
	@param data The complete IPv4 or IPv6 packet.
	@param filter_ref The reference to the filter injecting the data
	@param options Output options for the packet
	@result 0 on success otherwise the errno error. ipf_inject_output
		will always free the mbuf.
 */
extern errno_t ipf_inject_output(mbuf_t data, ipfilter_t filter_ref,
    ipf_pktopts_t options);

__END_DECLS
#endif /* __KPI_IPFILTER__ */
Commit	Line	Data
91447636	1	/*
6d2010ae	2	* Copyright (c) 2008-2010 Apple Inc. All rights reserved.
91447636	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_ipfilter.h
	30	This header defines an API to attach IP filters. IP filters may be
	31	attached to intercept either IPv4 or IPv6 packets. The filters can
	32	intercept all IP packets in to and out of the host regardless of
	33	interface.
	34	*/
	35
	36	#ifndef __KPI_IPFILTER__
	37	#define __KPI_IPFILTER__
	38
	39	#include <sys/kernel_types.h>
	40
	41	/*
	42	* ipf_pktopts
	43	*
	44	* Options for outgoing packets. The options need to be preserved when
	45	* re-injecting a packet.
	46	*/
	47	struct ipf_pktopts {
	48	u_int32_t ippo_flags;
	49	ifnet_t ippo_mcast_ifnet;
b0d623f7	50	int ippo_mcast_loop;
91447636 A	51	u_int8_t ippo_mcast_ttl;
91447636 A	52	};
6d2010ae A	53	#define IPPOF_MCAST_OPTS 0x1
	54	#ifdef PRIVATE
	55	#define IPPOF_BOUND_IF 0x2
	56	#define IPPOF_NO_IFT_CELLULAR 0x4
	57	#define IPPOF_SHIFT_IFSCOPE 16
	58	#endif /* PRIVATE */
91447636	59
b0d623f7	60	typedef struct ipf_pktopts *ipf_pktopts_t;
91447636	61
2d21ac55 A	62	__BEGIN_DECLS
2d21ac55 A	63
91447636 A	64	/*!
91447636 A	65	@typedef ipf_input_func
b0d623f7	66
91447636 A	67	@discussion ipf_input_func is used to filter incoming ip packets.
	68	The IP filter is called for packets from all interfaces. The
	69	filter is called between when the general IP processing is
	70	handled and when the packet is passed up to the next layer
	71	protocol such as udp or tcp. In the case of encapsulation, such
	72	as UDP in ESP (IPSec), your filter will be called once for ESP
	73	and then again for UDP. This will give your filter an
	74	opportunity to process the ESP header as well as the decrypted
	75	packet. Offset and protocol are used to determine where in the
	76	packet processing is currently occuring. If you're only
	77	interested in TCP or UDP packets, just return 0 if protocol
	78	doesn't match TCP or UDP.
	79	@param cookie The cookie specified when your filter was attached.
	80	@param data The reassembled ip packet, data will start at the ip
	81	header.
	82	@param offset An offset to the next header
	83	(udp/tcp/icmp/esp/etc...).
	84	@param protocol The protocol type (udp/tcp/icmp/etc...) of the IP packet
	85	@result Return:
b0d623f7 A	86	0 - The caller will continue with normal processing of the
	87	packet.
	88	EJUSTRETURN - The caller will stop processing the packet,
	89	the packet will not be freed.
	90	Anything Else - The caller will free the packet and stop
	91	processing.
91447636	92	*/
b0d623f7 A	93	typedef errno_t (ipf_input_func)(void cookie, mbuf_t *data, int offset,
b0d623f7 A	94	u_int8_t protocol);
91447636 A	95
	96	/*!
	97	@typedef ipf_output_func
b0d623f7	98
91447636 A	99	@discussion ipf_output_func is used to filter outbound ip packets.
	100	The IP filter is called for packets to all interfaces. The
	101	filter is called before fragmentation and IPSec processing. If
	102	you need to change the destination IP address, call
	103	ipf_inject_output and return EJUSTRETURN.
	104	@param cookie The cookie specified when your filter was attached.
	105	@param data The ip packet, will contain an IP header followed by the
	106	rest of the IP packet.
	107	@result Return:
b0d623f7 A	108	0 - The caller will continue with normal processing of the
	109	packet.
	110	EJUSTRETURN - The caller will stop processing the packet,
	111	the packet will not be freed.
	112	Anything Else - The caller will free the packet and stop
	113	processing.
91447636	114	*/
b0d623f7 A	115	typedef errno_t (ipf_output_func)(void cookie, mbuf_t *data,
b0d623f7 A	116	ipf_pktopts_t options);
91447636 A	117
	118	/*!
	119	@typedef ipf_detach_func
b0d623f7	120
91447636 A	121	@discussion ipf_detach_func is called to notify your filter that it
	122	has been detached.
	123	@param cookie The cookie specified when your filter was attached.
	124	*/
b0d623f7	125	typedef void (ipf_detach_func)(void cookie);
91447636 A	126
	127	/*!
	128	@typedef ipf_filter
	129	@discussion This structure is used to define an IP filter for
	130	use with the ipf_addv4 or ipf_addv6 function.
	131	@field cookie A kext defined cookie that will be passed to all
	132	filter functions.
	133	@field name A filter name used for debugging purposes.
	134	@field ipf_input The filter function to handle inbound packets.
	135	@field ipf_output The filter function to handle outbound packets.
	136	@field ipf_detach The filter function to notify of a detach.
	137	*/
	138	struct ipf_filter {
b0d623f7 A	139	void *cookie;
b0d623f7 A	140	const char *name;
91447636 A	141	ipf_input_func ipf_input;
	142	ipf_output_func ipf_output;
	143	ipf_detach_func ipf_detach;
	144	};
	145
	146	struct opaque_ipfilter;
b0d623f7	147	typedef struct opaque_ipfilter *ipfilter_t;
91447636 A	148
	149	/*!
	150	@function ipf_addv4
	151	@discussion Attaches an IPv4 ip filter.
	152	@param filter A structure defining the filter.
	153	@param filter_ref A reference to the filter used to detach it.
	154	@result 0 on success otherwise the errno error.
	155	*/
b0d623f7 A	156	extern errno_t ipf_addv4(const struct ipf_filter *filter,
b0d623f7 A	157	ipfilter_t *filter_ref);
91447636 A	158
	159	/*!
	160	@function ipf_addv6
	161	@discussion Attaches an IPv6 ip filter.
	162	@param filter A structure defining the filter.
	163	@param filter_ref A reference to the filter used to detach it.
	164	@result 0 on success otherwise the errno error.
	165	*/
b0d623f7 A	166	extern errno_t ipf_addv6(const struct ipf_filter *filter,
b0d623f7 A	167	ipfilter_t *filter_ref);
91447636 A	168
	169	/*!
	170	@function ipf_remove
	171	@discussion Detaches an IPv4 or IPv6 filter.
	172	@param filter_ref The reference to the filter returned from ipf_addv4 or
	173	ipf_addv6.
	174	@result 0 on success otherwise the errno error.
	175	*/
b0d623f7	176	extern errno_t ipf_remove(ipfilter_t filter_ref);
91447636 A	177
	178	/*!
	179	@function ipf_inject_input
	180	@discussion Inject an IP packet as though it had just been
	181	reassembled in ip_input. When re-injecting a packet intercepted
	182	by the filter's ipf_input function, an IP filter can pass its
	183	reference to avoid processing the packet twice. This also
	184	prevents ip filters installed before this filter from
	185	getting a chance to process the packet. If the filter modified
	186	the packet, it should not specify the filter ref to give other
	187	filters a chance to process the new packet.
b0d623f7	188
91447636 A	189	Caller is responsible for freeing mbuf chain in the event that
	190	ipf_inject_input returns an error.
	191	@param data The complete IPv4 or IPv6 packet, receive interface must
	192	be set.
	193	@param filter_ref The reference to the filter injecting the data
	194	@result 0 on success otherwise the errno error.
	195	*/
b0d623f7	196	extern errno_t ipf_inject_input(mbuf_t data, ipfilter_t filter_ref);
91447636 A	197
	198	/*!
	199	@function ipf_inject_output
	200	@discussion Inject an IP packet as though it had just been sent to
	201	ip_output. When re-injecting a packet intercepted by the
	202	filter's ipf_output function, an IP filter can pass its
	203	reference to avoid processing the packet twice. This also
	204	prevents ip filters installed before this filter from getting a
	205	chance to process the packet. If the filter modified the packet,
	206	it should not specify the filter ref to give other filters a
	207	chance to process the new packet.
	208	@param data The complete IPv4 or IPv6 packet.
	209	@param filter_ref The reference to the filter injecting the data
	210	@param options Output options for the packet
	211	@result 0 on success otherwise the errno error. ipf_inject_output
	212	will always free the mbuf.
	213	*/
b0d623f7 A	214	extern errno_t ipf_inject_output(mbuf_t data, ipfilter_t filter_ref,
b0d623f7 A	215	ipf_pktopts_t options);
91447636	216
2d21ac55	217	__END_DECLS
91447636	218	#endif /* __KPI_IPFILTER__ */