1/*
2 * Copyright (c) 2008 Apple Computer, 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_socketfilter.h
30	This header defines an API for intercepting communications at the
31	socket layer.
32
33	For the most part, socket filters want to do three things: Filter
34	data in and out, watch for state changes, and intercept a few calls
35	for security. The number of function pointers supplied by a socket
36	filter has been significantly reduced. The filter no longer has any
37	knowledge of socket buffers. The filter no longer intercepts nearly
38	every internal socket call. There are two data filters, an in
39	filter, and an out filter. The in filter occurs before data is
40	placed in the receive socket buffer. This is done to avoid waking
41	the process unnecessarily. The out filter occurs before the data is
42	appended to the send socket buffer. This should cover inbound and
43	outbound data. For monitoring state changes, we've added a notify
44	function that will be called when various events that the filter can
45	not intercept occur. In addition, we've added a few functions that a
46	filter may use to intercept common operations. These functions are:
47	connect (inbound), connect (outbound), bind, set socket option,
48	get socket option, and listen. Bind, listen, connect in, and connect
49	out could be used together to build a fairly comprehensive firewall
50	without having to do much with individual packets.
51 */
52#ifndef __KPI_SOCKETFILTER__
53#define __KPI_SOCKETFILTER__
54
55#include <sys/kernel_types.h>
56#include <sys/kpi_socket.h>
57
58struct sockaddr;
59
60/*!
61	@enum sflt_flags
62	@abstract Constants defining mbuf flags. Only the flags listed below
63		can be set or retrieved.
64	@constant SFLT_GLOBAL Indicates this socket filter should be
65		attached to all new sockets when they're created.
66	@constant SFLT_PROG Indicates this socket filter should be attached
67		only when request by the application using the SO_NKE socket
68		option.
69	@constant SFLT_EXTENDED	Indicates that this socket filter utilizes
70		the extended fields within the sflt_filter structure.
71	@constant SFLT_EXTENDED_REGISTRY Indicates that this socket filter
72		wants to attach to all the sockets already present on the
73		system. It will also receive notifications for these sockets.
74*/
75enum {
76	SFLT_GLOBAL		= 0x01,
77	SFLT_PROG		= 0x02,
78	SFLT_EXTENDED		= 0x04,
79	SFLT_EXTENDED_REGISTRY	= 0x08
80};
81typedef	u_int32_t	sflt_flags;
82
83/*!
84	@typedef sflt_handle
85	@abstract A 4 byte identifier used with the SO_NKE socket option to
86		identify the socket filter to be attached.
87*/
88typedef	u_int32_t	sflt_handle;
89
90/*!
91	@enum sflt_event_t
92	@abstract Events notify a filter of state changes and other various
93		events related to the socket. These events cannot be prevented
94		or intercepted, only observed.
95	@constant sock_evt_connected Indicates this socket has moved to the
96		connected state.
97	@constant sock_evt_disconnected Indicates this socket has moved to
98		the disconnected state.
99	@constant sock_evt_flush_read The read socket buffer has been
100		flushed.
101	@constant sock_evt_shutdown The read and or write side(s) of the
102		connection have been shutdown. The param will point to an
103		integer that indicates the direction that has been shutdown. See
104		'man 2 shutdown' for more information.
105	@constant sock_evt_cantrecvmore Indicates the socket cannot receive
106		more data.
107	@constant sock_evt_cantsendmore Indicates the socket cannot send
108		more data.
109	@constant sock_evt_closing Indicates the socket is closing.
110	@constant sock_evt_bound Indicates this socket has moved to the
111		bound state (only for PF_INET/PF_INET6 domain).
112*/
113enum {
114	sock_evt_connecting		= 1,
115	sock_evt_connected		= 2,
116	sock_evt_disconnecting		= 3,
117	sock_evt_disconnected		= 4,
118	sock_evt_flush_read		= 5,
119	sock_evt_shutdown		= 6, /* param points to an integer specifying how (read, write, or both) see man 2 shutdown */
120	sock_evt_cantrecvmore		= 7,
121	sock_evt_cantsendmore		= 8,
122	sock_evt_closing		= 9,
123	sock_evt_bound			= 10
124};
125typedef	u_int32_t	sflt_event_t;
126
127/*!
128	@enum sflt_data_flag_t
129	@abstract Inbound and outbound data filters may handle many
130		different types of incoming and outgoing data. These flags help
131		distinguish between normal data, out-of-band data, and records.
132	@constant sock_data_filt_flag_oob Indicates this data is out-of-band
133		data.
134	@constant sock_data_filt_flag_record Indicates this data is a
135		record. This flag is only ever seen on inbound data.
136*/
137enum {
138	sock_data_filt_flag_oob		= 1,
139	sock_data_filt_flag_record	= 2
140};
141typedef	u_int32_t	sflt_data_flag_t;
142
143__BEGIN_DECLS
144
145/*!
146	@typedef sf_unregistered_func
147
148	@discussion sf_unregistered_func is called to notify the filter it
149		has been unregistered. This is the last function the stack will
150		call and this function will only be called once all other
151		function calls in to your filter have completed. Once this
152		function has been called, your kext may safely unload.
153	@param handle The socket filter handle used to identify this filter.
154*/
155typedef	void (*sf_unregistered_func)(sflt_handle handle);
156
157/*!
158	@typedef sf_attach_func
159
160	@discussion sf_attach_func is called to notify the filter it has
161		been attached to a socket. The filter may allocate memory for
162		this attachment and use the cookie to track it. This filter is
163		called in one of two cases:
164		1) You've installed a global filter and a new socket was created.
165		2) Your non-global socket filter is being attached using the SO_NKE
166		socket option.
167	@param cookie Used to allow the socket filter to set the cookie for
168		this attachment.
169	@param so The socket the filter is being attached to.
170	@result If you return a non-zero value, your filter will not be
171		attached to this socket.
172*/
173typedef	errno_t	(*sf_attach_func)(void	**cookie, socket_t so);
174
175/*!
176	@typedef sf_detach_func
177
178	@discussion sf_detach_func is called to notify the filter it has
179		been detached from a socket. If the filter allocated any memory
180		for this attachment, it should be freed. This function will
181		be called when the socket is disposed of.
182	@param cookie Cookie value specified when the filter attach was
183		called.
184	@param so The socket the filter is attached to.
185	@result If you return a non-zero value, your filter will not be
186		attached to this socket.
187*/
188typedef	void (*sf_detach_func)(void *cookie, socket_t so);
189
190/*!
191	@typedef sf_notify_func
192
193	@discussion sf_notify_func is called to notify the filter of various
194		state changes and other events occuring on the socket.
195	@param cookie Cookie value specified when the filter attach was
196		called.
197	@param so The socket the filter is attached to.
198	@param event The type of event that has occurred.
199	@param param Additional information about the event.
200*/
201typedef	void (*sf_notify_func)(void *cookie, socket_t so, sflt_event_t event,
202    void *param);
203
204/*!
205	@typedef sf_getpeername_func
206
207	@discussion sf_getpeername_func is called to allow a filter to
208		to intercept the getpeername function. When called, sa will
209		point to a pointer to a socket address that was malloced
210		in zone M_SONAME. If you want to replace this address, either
211		modify the currenty copy or allocate a new one and free the
212		old one.
213	@param cookie Cookie value specified when the filter attach was
214		called.
215	@param so The socket the filter is attached to.
216	@param sa A pointer to a socket address pointer.
217	@result If you return a non-zero value, processing will stop. If
218		you return EJUSTRETURN, no further filters will be called
219		but a result of zero will be returned to the caller of
220		getpeername.
221*/
222typedef	int (*sf_getpeername_func)(void *cookie, socket_t so,
223    struct sockaddr **sa);
224
225/*!
226	@typedef sf_getsockname_func
227
228	@discussion sf_getsockname_func is called to allow a filter to
229		to intercept the getsockname function. When called, sa will
230		point to a pointer to a socket address that was malloced
231		in zone M_SONAME. If you want to replace this address, either
232		modify the currenty copy or allocate a new one and free the
233		old one.
234	@param cookie Cookie value specified when the filter attach was
235		called.
236	@param so The socket the filter is attached to.
237	@param sa A pointer to a socket address pointer.
238	@result If you return a non-zero value, processing will stop. If
239		you return EJUSTRETURN, no further filters will be called
240		but a result of zero will be returned to the caller of
241		getsockname.
242*/
243typedef	int (*sf_getsockname_func)(void *cookie, socket_t so,
244    struct sockaddr **sa);
245
246/*!
247	@typedef sf_data_in_func
248
249	@discussion sf_data_in_func is called to filter incoming data. If your
250		filter intercepts data for later reinjection, it must queue
251		all incoming data to preserve the order of the data. Use
252		sock_inject_data_in to later reinject this data if you return
253		EJUSTRETURN. Warning: This filter is on the data path. Do not
254		spend excesive time. Do not wait for data on another socket.
255	@param cookie Cookie value specified when the filter attach was
256		called.
257	@param so The socket the filter is attached to.
258	@param from The addres the data is from, may be NULL if the socket
259		is connected.
260	@param data The data being received. Control data may appear in the
261		mbuf chain, be sure to check the mbuf types to find control
262		data.
263	@param control Control data being passed separately from the data.
264	@param flags Flags to indicate if this is out of band data or a
265		record.
266	@result Return:
267		0 - The caller will continue with normal processing of the data.
268		EJUSTRETURN - The caller will stop processing the data, the
269			data will not be freed.
270		Anything Else - The caller will free the data and stop
271			processing.
272*/
273typedef	errno_t	(*sf_data_in_func)(void *cookie, socket_t so,
274    const struct sockaddr *from, mbuf_t *data, mbuf_t *control,
275    sflt_data_flag_t flags);
276
277/*!
278	@typedef sf_data_out_func
279
280	@discussion sf_data_out_func is called to filter outbound data. If
281		your filter intercepts data for later reinjection, it must queue
282		all outbound data to preserve the order of the data when
283		reinjecting. Use sock_inject_data_out to later reinject this
284		data.
285	@param cookie Cookie value specified when the filter attach was
286		called.
287	@param so The socket the filter is attached to.
288	@param from The address the data is from, may be NULL if the socket
289		is connected.
290	@param data The data being received. Control data may appear in the
291		mbuf chain, be sure to check the mbuf types to find control
292		data.
293	@param control Control data being passed separately from the data.
294	@param flags Flags to indicate if this is out of band data or a
295		record.
296	@result Return:
297		0 - The caller will continue with normal processing of the data.
298		EJUSTRETURN - The caller will stop processing the data,
299			the data will not be freed.
300		Anything Else - The caller will free the data and stop
301			processing.
302*/
303typedef	errno_t	(*sf_data_out_func)(void *cookie, socket_t so,
304    const struct sockaddr *to, mbuf_t *data, mbuf_t *control,
305    sflt_data_flag_t flags);
306
307/*!
308	@typedef sf_connect_in_func
309
310	@discussion sf_connect_in_func is called to filter inbound connections.
311		A protocol will call this before accepting an incoming
312		connection and placing it on the queue of completed connections.
313		Warning: This filter is on the data path. Do not spend excesive
314		time. Do not wait for data on another socket.
315	@param cookie Cookie value specified when the filter attach was
316		called.
317	@param so The socket the filter is attached to.
318	@param from The address the incoming connection is from.
319	@result Return:
320		0 - The caller will continue with normal processing of the
321			connection.
322		Anything Else - The caller will rejecting the incoming
323			connection.
324*/
325typedef	errno_t	(*sf_connect_in_func)(void *cookie, socket_t so,
326    const struct sockaddr *from);
327
328/*!
329	@typedef sf_connect_out_func
330
331	@discussion sf_connect_out_func is called to filter outbound
332		connections. A protocol will call this before initiating an
333		outbound connection.
334	@param cookie Cookie value specified when the filter attach was
335		called.
336	@param so The socket the filter is attached to.
337	@param to The remote address of the outbound connection.
338	@result Return:
339		0 - The caller will continue with normal processing of the
340			connection.
341		EJUSTRETURN - The caller will return with a value of 0 (no error)
342			from that point without further processing the connect command. The
343			protocol layer will not see the call.
344		Anything Else - The caller will rejecting the outbound
345			connection.
346*/
347typedef	errno_t	(*sf_connect_out_func)(void *cookie, socket_t so,
348    const struct sockaddr *to);
349
350/*!
351	@typedef sf_bind_func
352
353	@discussion sf_bind_func is called before performing a bind
354		operation on a socket.
355	@param cookie Cookie value specified when the filter attach was
356		called.
357	@param so The socket the filter is attached to.
358	@param to The local address of the socket will be bound to.
359	@result Return:
360		0 - The caller will continue with normal processing of the bind.
361		EJUSTRETURN - The caller will return with a value of 0 (no error)
362			from that point without further processing the bind command. The
363			protocol layer will not see the call.
364		Anything Else - The caller will rejecting the bind.
365*/
366typedef	errno_t	(*sf_bind_func)(void *cookie, socket_t so,
367    const struct sockaddr *to);
368
369/*!
370	@typedef sf_setoption_func
371
372	@discussion sf_setoption_func is called before performing setsockopt
373		on a socket.
374	@param cookie Cookie value specified when the filter attach was
375		called.
376	@param so The socket the filter is attached to.
377	@param opt The socket option to set.
378	@result Return:
379		0 - The caller will continue with normal processing of the
380			setsockopt.
381		EJUSTRETURN - The caller will return with a value of 0 (no error)
382			from that point without further propagating the set option
383			command. The socket and protocol layers will not see the call.
384		Anything Else - The caller will stop processing and return
385			this error.
386*/
387typedef	errno_t	(*sf_setoption_func)(void *cookie, socket_t so, sockopt_t opt);
388
389/*!
390	@typedef sf_getoption_func
391
392	@discussion sf_getoption_func is called before performing getsockopt
393		on a socket.
394	@param cookie Cookie value specified when the filter attach was
395		called.
396	@param so The socket the filter is attached to.
397	@param opt The socket option to get.
398	@result Return:
399		0 - The caller will continue with normal processing of the
400			getsockopt.
401		EJUSTRETURN - The caller will return with a value of 0 (no error)
402			from that point without further propagating the get option
403			command. The socket and protocol layers will not see the call.
404		Anything Else - The caller will stop processing and return
405			this error.
406*/
407typedef	errno_t	(*sf_getoption_func)(void *cookie, socket_t so, sockopt_t opt);
408
409/*!
410	@typedef sf_listen_func
411
412	@discussion sf_listen_func is called before performing listen
413		on a socket.
414	@param cookie Cookie value specified when the filter attach was
415		called.
416	@param so The socket the filter is attached to.
417	@result Return:
418		0 - The caller will continue with normal processing of listen.
419		EJUSTRETURN - The caller will return with a value of 0 (no error)
420		from that point without further processing the listen command. The
421		protocol will not see the call.
422		Anything Else - The caller will stop processing and return
423			this error.
424*/
425typedef	errno_t	(*sf_listen_func)(void *cookie, socket_t so);
426
427/*!
428	@typedef sf_ioctl_func
429
430	@discussion sf_ioctl_func is called before performing an ioctl
431		on a socket.
432
433		All undefined ioctls are reserved for future use by Apple. If
434		you need to communicate with your kext using an ioctl, please
435		use SIOCSIFKPI and SIOCGIFKPI.
436	@param cookie Cookie value specified when the filter attach was
437		called.
438	@param so The socket the filter is attached to.
439	@param request The ioctl name.
440	@param argp A pointer to the ioctl parameter.
441	@result Return:
442		0 - The caller will continue with normal processing of
443			this ioctl.
444		EJUSTRETURN - The caller will return with a value of 0 (no error)
445			from that point without further processing or propogating
446			the ioctl.
447		Anything Else - The caller will stop processing and return
448			this error.
449*/
450typedef	errno_t	(*sf_ioctl_func)(void *cookie, socket_t so,
451    unsigned long request, const char* argp);
452
453/*!
454	@typedef sf_accept_func
455
456	@discussion sf_accept_func is called after a socket is dequeued
457		off the completed (incoming) connection list and before
458		the file descriptor is associated with it.  A filter can
459		utilize this callback to intercept the accepted socket
460		in order to examine it, prior to returning the socket to
461		the caller of accept.  Such a filter may also choose to
462		discard the accepted socket if it wishes to do so.
463	@param cookie Cookie value specified when the filter attach was called.
464	@param so_listen The listening socket.
465	@param so The socket that is about to be accepted.
466	@param local The local address of the about to be accepted socket.
467	@param remote The remote address of the about to be accepted socket.
468	@result Return:
469		0 - The caller will continue with normal processing of accept.
470		EJUSTRETURN - The to be accepted socket will be disconnected
471		    prior to being returned to the caller of accept.  No further
472		    control or data operations on the socket will be allowed.
473		    This is the recommended return value as it has the least
474		    amount of impact, especially to applications which don't
475		    check the error value returned by accept.
476		Anything Else - The to be accepted socket will be closed and
477		    the error will be returned to the caller of accept.
478		    Note that socket filter developers are advised to exercise
479		    caution when returning non-zero values to the caller,
480		    since some applications don't check the error value
481		    returned by accept and therefore risk breakage.
482 */
483typedef errno_t (*sf_accept_func)(void *cookie, socket_t so_listen, socket_t so,
484    const struct sockaddr *local, const struct sockaddr *remote);
485
486/*!
487	@struct sflt_filter
488	@discussion This structure is used to define a socket filter.
489	@field sf_handle A value used to find socket filters by
490		applications. An application can use this value to specify that
491		this filter should be attached when using the SO_NKE socket
492		option.
493	@field sf_flags Indicate whether this filter should be attached to
494		all new sockets or just those that request the filter be
495		attached using the SO_NKE socket option. If this filter
496		utilizes the socket filter extension fields, it must also
497		set SFLT_EXTENDED.
498	@field sf_name A name used for debug purposes.
499	@field sf_unregistered Your function for being notified when your
500		filter has been unregistered.
501	@field sf_attach Your function for handling attaches to sockets.
502	@field sf_detach Your function for handling detaches from sockets.
503	@field sf_notify Your function for handling events. May be null.
504	@field sf_data_in Your function for handling incoming data. May be
505		null.
506	@field sf_data_out Your function for handling outgoing data. May be
507		null.
508	@field sf_connect_in Your function for handling inbound
509		connections. May be null.
510	@field sf_connect_out Your function for handling outbound
511		connections. May be null.
512	@field sf_bind Your function for handling binds. May be null.
513	@field sf_setoption Your function for handling setsockopt. May be null.
514	@field sf_getoption Your function for handling getsockopt. May be null.
515	@field sf_listen Your function for handling listen. May be null.
516	@field sf_ioctl Your function for handling ioctls. May be null.
517	@field sf_len Length of socket filter extension structure; developers
518		must initialize this to sizeof sflt_filter_ext structure.
519		This field and all fields following it will only be valid
520		if SFLT_EXTENDED flag is set in sf_flags field.
521	@field sf_ext_accept Your function for handling inbound connections
522		at accept time.  May be null.
523	@field sf_ext_rsvd Reserved for future use; you must initialize
524		the reserved fields with zeroes.
525*/
526struct sflt_filter {
527	sflt_handle			sf_handle;
528	int				sf_flags;
529	char				*sf_name;
530
531	sf_unregistered_func		sf_unregistered;
532	sf_attach_func			sf_attach;
533	sf_detach_func			sf_detach;
534
535	sf_notify_func			sf_notify;
536	sf_getpeername_func		sf_getpeername;
537	sf_getsockname_func		sf_getsockname;
538	sf_data_in_func			sf_data_in;
539	sf_data_out_func		sf_data_out;
540	sf_connect_in_func		sf_connect_in;
541	sf_connect_out_func		sf_connect_out;
542	sf_bind_func			sf_bind;
543	sf_setoption_func		sf_setoption;
544	sf_getoption_func		sf_getoption;
545	sf_listen_func			sf_listen;
546	sf_ioctl_func			sf_ioctl;
547	/*
548	 * The following are valid only if SFLT_EXTENDED flag is set.
549	 * Initialize sf_ext_len to sizeof sflt_filter_ext structure.
550	 * Filters must also initialize reserved fields with zeroes.
551	 */
552	struct sflt_filter_ext {
553		unsigned int		sf_ext_len;
554		sf_accept_func		sf_ext_accept;
555		void			*sf_ext_rsvd[5];	/* Reserved */
556	} sf_ext;
557#define	sf_len		sf_ext.sf_ext_len
558#define	sf_accept	sf_ext.sf_ext_accept
559};
560
561/*!
562	@function sflt_register
563	@discussion Registers a socket filter. See 'man 2 socket' for a
564		desciption of domain, type, and protocol.
565	@param filter A structure describing the filter.
566	@param domain The protocol domain these filters will be attached to.
567	@param type The socket type these filters will be attached to.
568	@param protocol The protocol these filters will be attached to.
569	@result 0 on success otherwise the errno error.
570 */
571extern errno_t sflt_register(const struct sflt_filter *filter, int domain,
572    int type, int protocol);
573
574/*!
575	@function sflt_unregister
576	@discussion Unregisters a socket filter. This will not detach the
577		socket filter from all sockets it may be attached to at the
578		time, it will just prevent the socket filter from being attached
579		to any new sockets.
580	@param handle The sf_handle of the socket filter to unregister.
581	@result 0 on success otherwise the errno error.
582 */
583extern errno_t sflt_unregister(sflt_handle handle);
584
585/*!
586	@function sflt_attach
587	@discussion Attaches a socket filter to the specified socket. A
588		filter must be registered before it can be attached.
589	@param socket The socket the filter should be attached to.
590	@param handle The handle of the registered filter to be attached.
591	@result 0 on success otherwise the errno error.
592 */
593extern errno_t sflt_attach(socket_t so, sflt_handle);
594
595/*!
596	@function sflt_detach
597	@discussion Detaches a socket filter from a specified socket.
598	@param socket The socket the filter should be detached from.
599	@param handle The handle of the registered filter to be detached.
600	@result 0 on success otherwise the errno error.
601 */
602extern errno_t sflt_detach(socket_t so, sflt_handle);
603
604/* Functions for manipulating sockets */
605/*
606 * Inject data in to the receive buffer of the socket as if it
607 * had come from the network.
608 *
609 * flags should match sflt_data_flag_t
610 */
611
612/*!
613	@function sock_inject_data_in
614	@discussion Inject data in to the receive buffer of the socket as if
615		it had come from the network.
616	@param so The socket to inject the data on.
617	@param from The address the data is from, only necessary on
618		un-connected sockets. A copy of the address will be made, caller
619		is responsible for freeing the address after calling this
620		function.
621	@param data The data and possibly control mbufs.
622	@param control The separate control mbufs.
623	@param flags Flags indicating the type of data.
624	@result 0 on success otherwise the errno error. If the function
625		returns an error, the caller is responsible for freeing the
626		mbuf.
627 */
628extern errno_t sock_inject_data_in(socket_t so, const struct sockaddr *from,
629    mbuf_t data, mbuf_t control, sflt_data_flag_t flags);
630
631/*!
632	@function sock_inject_data_out
633	@discussion Inject data in to the send buffer of the socket as if it
634		had come from the client.
635	@param so The socket to inject the data on.
636	@param to The address the data should be sent to, only necessary on
637		un-connected sockets. The caller is responsible for freeing the
638		to address after sock_inject_data_out returns.
639	@param data The data and possibly control mbufs.
640	@param control The separate control mbufs.
641	@param flags Flags indicating the type of data.
642	@result 0 on success otherwise the errno error. The data and control
643		values are always freed regardless of return value.
644 */
645extern errno_t sock_inject_data_out(socket_t so, const struct sockaddr *to,
646    mbuf_t data, mbuf_t control, sflt_data_flag_t flags);
647
648
649/*
650 * sockopt_t accessors
651 */
652
653enum {
654	sockopt_get	= 1,
655	sockopt_set	= 2
656};
657typedef u_int8_t sockopt_dir;
658
659/*!
660	@function sockopt_direction
661	@discussion Retrieves the direction of the socket option (Get or
662		Set).
663	@param sopt The socket option.
664	@result sock_opt_get or sock_opt_set.
665 */
666extern sockopt_dir sockopt_direction(sockopt_t sopt);
667
668/*!
669	@function sockopt_level
670	@discussion Retrieves the socket option level. (SOL_SOCKET, etc).
671	@param sopt The socket option.
672	@result The socket option level. See man 2 setsockopt
673 */
674extern int sockopt_level(sockopt_t sopt);
675
676/*!
677	@function sockopt_name
678	@discussion Retrieves the socket option name. (SO_SNDBUF, etc).
679	@param sopt The socket option.
680	@result The socket option name. See man 2 setsockopt
681 */
682extern int sockopt_name(sockopt_t sopt);
683
684/*!
685	@function sockopt_valsize
686	@discussion Retrieves the size of the socket option data.
687	@param sopt The socket option.
688	@result The length, in bytes, of the data.
689 */
690extern size_t sockopt_valsize(sockopt_t sopt);
691
692/*!
693	@function sockopt_copyin
694	@discussion Copies the data from the socket option to a buffer.
695	@param sopt The socket option.
696	@param data A pointer to the buffer to copy the data in to.
697	@param length The number of bytes to copy.
698	@result An errno error or zero upon success.
699 */
700extern errno_t sockopt_copyin(sockopt_t sopt, void *data, size_t length);
701
702/*!
703	@function sockopt_copyout
704	@discussion Copies the data from a buffer to a socket option.
705	@param sopt The socket option.
706	@param data A pointer to the buffer to copy the data out of.
707	@param length The number of bytes to copy.
708	@result An errno error or zero upon success.
709 */
710extern errno_t sockopt_copyout(sockopt_t sopt, void *data, size_t length);
711
712__END_DECLS
713#endif /* __KPI_SOCKETFILTER__ */
714