xref: /freebsd/sys/netgraph/netgraph.h (revision 40a8ac8f62b535d30349faf28cf47106b7041b83)
1 /*
2  * netgraph.h
3  */
4 
5 /*-
6  * Copyright (c) 1996-1999 Whistle Communications, Inc.
7  * All rights reserved.
8  *
9  * Subject to the following obligations and disclaimer of warranty, use and
10  * redistribution of this software, in source or object code forms, with or
11  * without modifications are expressly permitted by Whistle Communications;
12  * provided, however, that:
13  * 1. Any and all reproductions of the source or object code must include the
14  *    copyright notice above and the following disclaimer of warranties; and
15  * 2. No rights are granted, in any manner or form, to use Whistle
16  *    Communications, Inc. trademarks, including the mark "WHISTLE
17  *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
18  *    such appears in the above copyright notice or in the software.
19  *
20  * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
21  * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
22  * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
23  * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
24  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
25  * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
26  * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
27  * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
28  * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
29  * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
30  * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
31  * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
32  * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
33  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35  * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
36  * OF SUCH DAMAGE.
37  *
38  * Author: Julian Elischer <julian@freebsd.org>
39  *
40  * $FreeBSD$
41  * $Whistle: netgraph.h,v 1.29 1999/11/01 07:56:13 julian Exp $
42  */
43 
44 #ifndef _NETGRAPH_NETGRAPH_H_
45 #define _NETGRAPH_NETGRAPH_H_
46 
47 #ifndef _KERNEL
48 #error "This file should not be included in user level programs"
49 #endif
50 
51 #include <sys/queue.h>
52 #include <sys/lock.h>
53 #include <sys/malloc.h>
54 #include <sys/module.h>
55 #include <sys/mutex.h>
56 #include <sys/refcount.h>
57 
58 #ifdef HAVE_KERNEL_OPTION_HEADERS
59 #include "opt_netgraph.h"
60 #include "opt_kdb.h"
61 #endif
62 
63 /* debugging options */
64 #define NG_SEPARATE_MALLOC	/* make modules use their own malloc types */
65 
66 /*
67  * This defines the in-kernel binary interface version.
68  * It is possible to change this but leave the external message
69  * API the same. Each type also has it's own cookies for versioning as well.
70  * Change it for NETGRAPH_DEBUG version so we cannot mix debug and non debug
71  * modules.
72  */
73 #define _NG_ABI_VERSION 12
74 #ifdef	NETGRAPH_DEBUG /*----------------------------------------------*/
75 #define NG_ABI_VERSION	(_NG_ABI_VERSION + 0x10000)
76 #else	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
77 #define NG_ABI_VERSION	_NG_ABI_VERSION
78 #endif	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
79 
80 
81 /*
82  * Forward references for the basic structures so we can
83  * define the typedefs and use them in the structures themselves.
84  */
85 struct ng_hook ;
86 struct ng_node ;
87 struct ng_item ;
88 typedef	struct ng_item *item_p;
89 typedef struct ng_node *node_p;
90 typedef struct ng_hook *hook_p;
91 
92 /* node method definitions */
93 typedef	int	ng_constructor_t(node_p node);
94 typedef	int	ng_close_t(node_p node);
95 typedef	int	ng_shutdown_t(node_p node);
96 typedef	int	ng_newhook_t(node_p node, hook_p hook, const char *name);
97 typedef	hook_p	ng_findhook_t(node_p node, const char *name);
98 typedef	int	ng_connect_t(hook_p hook);
99 typedef	int	ng_rcvmsg_t(node_p node, item_p item, hook_p lasthook);
100 typedef	int	ng_rcvdata_t(hook_p hook, item_p item);
101 typedef	int	ng_disconnect_t(hook_p hook);
102 typedef	int	ng_rcvitem (node_p node, hook_p hook, item_p item);
103 
104 /***********************************************************************
105  ***************** Hook Structure and Methods **************************
106  ***********************************************************************
107  *
108  * Structure of a hook
109  */
110 struct ng_hook {
111 	char	hk_name[NG_HOOKSIZ];	/* what this node knows this link as */
112 	void   *hk_private;		/* node dependant ID for this hook */
113 	int	hk_flags;		/* info about this hook/link */
114 	int	hk_type;		/* tbd: hook data link type */
115 	struct	ng_hook *hk_peer;	/* the other end of this link */
116 	struct	ng_node *hk_node;	/* The node this hook is attached to */
117 	LIST_ENTRY(ng_hook) hk_hooks;	/* linked list of all hooks on node */
118 	ng_rcvmsg_t	*hk_rcvmsg;	/* control messages come here */
119 	ng_rcvdata_t	*hk_rcvdata;	/* data comes here */
120 	int	hk_refs;		/* dont actually free this till 0 */
121 #ifdef	NETGRAPH_DEBUG /*----------------------------------------------*/
122 #define HK_MAGIC 0x78573011
123 	int	hk_magic;
124 	char	*lastfile;
125 	int	lastline;
126 	SLIST_ENTRY(ng_hook)	  hk_all;		/* all existing items */
127 #endif	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
128 };
129 /* Flags for a hook */
130 #define HK_INVALID		0x0001	/* don't trust it! */
131 #define HK_QUEUE		0x0002	/* queue for later delivery */
132 #define HK_FORCE_WRITER		0x0004	/* Incoming data queued as a writer */
133 #define HK_DEAD			0x0008	/* This is the dead hook.. don't free */
134 #define HK_HI_STACK		0x0010	/* Hook has hi stack usage */
135 #define HK_TO_INBOUND		0x0020	/* Hook on ntw. stack inbound path. */
136 
137 /*
138  * Public Methods for hook
139  * If you can't do it with these you probably shouldn;t be doing it.
140  */
141 void ng_unref_hook(hook_p hook); /* don't move this */
142 #define	_NG_HOOK_REF(hook)	refcount_acquire(&(hook)->hk_refs)
143 #define _NG_HOOK_NAME(hook)	((hook)->hk_name)
144 #define _NG_HOOK_UNREF(hook)	ng_unref_hook(hook)
145 #define	_NG_HOOK_SET_PRIVATE(hook, val)	do {(hook)->hk_private = val;} while (0)
146 #define	_NG_HOOK_SET_RCVMSG(hook, val)	do {(hook)->hk_rcvmsg = val;} while (0)
147 #define	_NG_HOOK_SET_RCVDATA(hook, val)	do {(hook)->hk_rcvdata = val;} while (0)
148 #define	_NG_HOOK_PRIVATE(hook)	((hook)->hk_private)
149 #define _NG_HOOK_NOT_VALID(hook)	((hook)->hk_flags & HK_INVALID)
150 #define _NG_HOOK_IS_VALID(hook)	(!((hook)->hk_flags & HK_INVALID))
151 #define _NG_HOOK_NODE(hook)	((hook)->hk_node) /* only rvalue! */
152 #define _NG_HOOK_PEER(hook)	((hook)->hk_peer) /* only rvalue! */
153 #define _NG_HOOK_FORCE_WRITER(hook)				\
154 		do { hook->hk_flags |= HK_FORCE_WRITER; } while (0)
155 #define _NG_HOOK_FORCE_QUEUE(hook) do { hook->hk_flags |= HK_QUEUE; } while (0)
156 #define _NG_HOOK_SET_TO_INBOUND(hook)				\
157 		do { hook->hk_flags |= HK_TO_INBOUND; } while (0)
158 #define _NG_HOOK_HI_STACK(hook) do { hook->hk_flags |= HK_HI_STACK; } while (0)
159 
160 /* Some shortcuts */
161 #define NG_PEER_NODE(hook)	NG_HOOK_NODE(NG_HOOK_PEER(hook))
162 #define NG_PEER_HOOK_NAME(hook)	NG_HOOK_NAME(NG_HOOK_PEER(hook))
163 #define NG_PEER_NODE_NAME(hook)	NG_NODE_NAME(NG_PEER_NODE(hook))
164 
165 #ifdef	NETGRAPH_DEBUG /*----------------------------------------------*/
166 #define _NN_ __FILE__,__LINE__
167 void	dumphook (hook_p hook, char *file, int line);
168 static __inline void	_chkhook(hook_p hook, char *file, int line);
169 static __inline void	_ng_hook_ref(hook_p hook, char * file, int line);
170 static __inline char *	_ng_hook_name(hook_p hook, char * file, int line);
171 static __inline void	_ng_hook_unref(hook_p hook, char * file, int line);
172 static __inline void	_ng_hook_set_private(hook_p hook,
173 				void * val, char * file, int line);
174 static __inline void	_ng_hook_set_rcvmsg(hook_p hook,
175 				ng_rcvmsg_t *val, char * file, int line);
176 static __inline void	_ng_hook_set_rcvdata(hook_p hook,
177 				ng_rcvdata_t *val, char * file, int line);
178 static __inline void *	_ng_hook_private(hook_p hook, char * file, int line);
179 static __inline int	_ng_hook_not_valid(hook_p hook, char * file, int line);
180 static __inline int	_ng_hook_is_valid(hook_p hook, char * file, int line);
181 static __inline node_p	_ng_hook_node(hook_p hook, char * file, int line);
182 static __inline hook_p	_ng_hook_peer(hook_p hook, char * file, int line);
183 static __inline void	_ng_hook_force_writer(hook_p hook, char * file,
184 				int line);
185 static __inline void	_ng_hook_force_queue(hook_p hook, char * file,
186 				int line);
187 static __inline void	_ng_hook_set_to_inbound(hook_p hook, char * file,
188 				int line);
189 
190 static __inline void
191 _chkhook(hook_p hook, char *file, int line)
192 {
193 	if (hook->hk_magic != HK_MAGIC) {
194 		printf("Accessing freed ");
195 		dumphook(hook, file, line);
196 	}
197 	hook->lastline = line;
198 	hook->lastfile = file;
199 }
200 
201 static __inline void
202 _ng_hook_ref(hook_p hook, char * file, int line)
203 {
204 	_chkhook(hook, file, line);
205 	_NG_HOOK_REF(hook);
206 }
207 
208 static __inline char *
209 _ng_hook_name(hook_p hook, char * file, int line)
210 {
211 	_chkhook(hook, file, line);
212 	return (_NG_HOOK_NAME(hook));
213 }
214 
215 static __inline void
216 _ng_hook_unref(hook_p hook, char * file, int line)
217 {
218 	_chkhook(hook, file, line);
219 	_NG_HOOK_UNREF(hook);
220 }
221 
222 static __inline void
223 _ng_hook_set_private(hook_p hook, void *val, char * file, int line)
224 {
225 	_chkhook(hook, file, line);
226 	_NG_HOOK_SET_PRIVATE(hook, val);
227 }
228 
229 static __inline void
230 _ng_hook_set_rcvmsg(hook_p hook, ng_rcvmsg_t *val, char * file, int line)
231 {
232 	_chkhook(hook, file, line);
233 	_NG_HOOK_SET_RCVMSG(hook, val);
234 }
235 
236 static __inline void
237 _ng_hook_set_rcvdata(hook_p hook, ng_rcvdata_t *val, char * file, int line)
238 {
239 	_chkhook(hook, file, line);
240 	_NG_HOOK_SET_RCVDATA(hook, val);
241 }
242 
243 static __inline void *
244 _ng_hook_private(hook_p hook, char * file, int line)
245 {
246 	_chkhook(hook, file, line);
247 	return (_NG_HOOK_PRIVATE(hook));
248 }
249 
250 static __inline int
251 _ng_hook_not_valid(hook_p hook, char * file, int line)
252 {
253 	_chkhook(hook, file, line);
254 	return (_NG_HOOK_NOT_VALID(hook));
255 }
256 
257 static __inline int
258 _ng_hook_is_valid(hook_p hook, char * file, int line)
259 {
260 	_chkhook(hook, file, line);
261 	return (_NG_HOOK_IS_VALID(hook));
262 }
263 
264 static __inline node_p
265 _ng_hook_node(hook_p hook, char * file, int line)
266 {
267 	_chkhook(hook, file, line);
268 	return (_NG_HOOK_NODE(hook));
269 }
270 
271 static __inline hook_p
272 _ng_hook_peer(hook_p hook, char * file, int line)
273 {
274 	_chkhook(hook, file, line);
275 	return (_NG_HOOK_PEER(hook));
276 }
277 
278 static __inline void
279 _ng_hook_force_writer(hook_p hook, char * file, int line)
280 {
281 	_chkhook(hook, file, line);
282 	_NG_HOOK_FORCE_WRITER(hook);
283 }
284 
285 static __inline void
286 _ng_hook_force_queue(hook_p hook, char * file, int line)
287 {
288 	_chkhook(hook, file, line);
289 	_NG_HOOK_FORCE_QUEUE(hook);
290 }
291 
292 static __inline void
293 _ng_hook_set_to_inbound(hook_p hook, char * file, int line)
294 {
295 	_chkhook(hook, file, line);
296 	_NG_HOOK_SET_TO_INBOUND(hook);
297 }
298 
299 static __inline void
300 _ng_hook_hi_stack(hook_p hook, char * file, int line)
301 {
302 	_chkhook(hook, file, line);
303 	_NG_HOOK_HI_STACK(hook);
304 }
305 
306 
307 #define	NG_HOOK_REF(hook)		_ng_hook_ref(hook, _NN_)
308 #define NG_HOOK_NAME(hook)		_ng_hook_name(hook, _NN_)
309 #define NG_HOOK_UNREF(hook)		_ng_hook_unref(hook, _NN_)
310 #define	NG_HOOK_SET_PRIVATE(hook, val)	_ng_hook_set_private(hook, val, _NN_)
311 #define	NG_HOOK_SET_RCVMSG(hook, val)	_ng_hook_set_rcvmsg(hook, val, _NN_)
312 #define	NG_HOOK_SET_RCVDATA(hook, val)	_ng_hook_set_rcvdata(hook, val, _NN_)
313 #define	NG_HOOK_PRIVATE(hook)		_ng_hook_private(hook, _NN_)
314 #define NG_HOOK_NOT_VALID(hook)		_ng_hook_not_valid(hook, _NN_)
315 #define NG_HOOK_IS_VALID(hook)		_ng_hook_is_valid(hook, _NN_)
316 #define NG_HOOK_NODE(hook)		_ng_hook_node(hook, _NN_)
317 #define NG_HOOK_PEER(hook)		_ng_hook_peer(hook, _NN_)
318 #define NG_HOOK_FORCE_WRITER(hook)	_ng_hook_force_writer(hook, _NN_)
319 #define NG_HOOK_FORCE_QUEUE(hook)	_ng_hook_force_queue(hook, _NN_)
320 #define NG_HOOK_SET_TO_INBOUND(hook)	_ng_hook_set_to_inbound(hook, _NN_)
321 #define NG_HOOK_HI_STACK(hook)		_ng_hook_hi_stack(hook, _NN_)
322 
323 #else	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
324 
325 #define	NG_HOOK_REF(hook)		_NG_HOOK_REF(hook)
326 #define NG_HOOK_NAME(hook)		_NG_HOOK_NAME(hook)
327 #define NG_HOOK_UNREF(hook)		_NG_HOOK_UNREF(hook)
328 #define	NG_HOOK_SET_PRIVATE(hook, val)	_NG_HOOK_SET_PRIVATE(hook, val)
329 #define	NG_HOOK_SET_RCVMSG(hook, val)	_NG_HOOK_SET_RCVMSG(hook, val)
330 #define	NG_HOOK_SET_RCVDATA(hook, val)	_NG_HOOK_SET_RCVDATA(hook, val)
331 #define	NG_HOOK_PRIVATE(hook)		_NG_HOOK_PRIVATE(hook)
332 #define NG_HOOK_NOT_VALID(hook)		_NG_HOOK_NOT_VALID(hook)
333 #define NG_HOOK_IS_VALID(hook)		_NG_HOOK_IS_VALID(hook)
334 #define NG_HOOK_NODE(hook)		_NG_HOOK_NODE(hook)
335 #define NG_HOOK_PEER(hook)		_NG_HOOK_PEER(hook)
336 #define NG_HOOK_FORCE_WRITER(hook)	_NG_HOOK_FORCE_WRITER(hook)
337 #define NG_HOOK_FORCE_QUEUE(hook)	_NG_HOOK_FORCE_QUEUE(hook)
338 #define NG_HOOK_SET_TO_INBOUND(hook)	_NG_HOOK_SET_TO_INBOUND(hook)
339 #define NG_HOOK_HI_STACK(hook)		_NG_HOOK_HI_STACK(hook)
340 
341 #endif	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
342 
343 /***********************************************************************
344  ***************** Node Structure and Methods **************************
345  ***********************************************************************
346  * Structure of a node
347  * including the eembedded queue structure.
348  *
349  * The structure for queueing Netgraph request items
350  * embedded in the node structure
351  */
352 struct ng_queue {
353 	u_int		q_flags;	/* Current r/w/q lock flags */
354 	u_int		q_flags2;	/* Other queue flags */
355 	struct mtx	q_mtx;
356 	STAILQ_ENTRY(ng_node)	q_work;	/* nodes with work to do */
357 	STAILQ_HEAD(, ng_item)	queue;	/* actually items queue */
358 };
359 
360 struct ng_node {
361 	char	nd_name[NG_NODESIZ];	/* optional globally unique name */
362 	struct	ng_type *nd_type;	/* the installed 'type' */
363 	int	nd_flags;		/* see below for bit definitions */
364 	int	nd_numhooks;		/* number of hooks */
365 	void   *nd_private;		/* node type dependant node ID */
366 	ng_ID_t	nd_ID;			/* Unique per node */
367 	LIST_HEAD(hooks, ng_hook) nd_hooks;	/* linked list of node hooks */
368 	LIST_ENTRY(ng_node)	  nd_nodes;	/* name hash collision list */
369 	LIST_ENTRY(ng_node)	  nd_idnodes;	/* ID hash collision list */
370 	struct	ng_queue	  nd_input_queue; /* input queue for locking */
371 	int	nd_refs;		/* # of references to this node */
372 	struct	vnet		 *nd_vnet;	/* network stack instance */
373 #ifdef	NETGRAPH_DEBUG /*----------------------------------------------*/
374 #define ND_MAGIC 0x59264837
375 	int	nd_magic;
376 	char	*lastfile;
377 	int	lastline;
378 	SLIST_ENTRY(ng_node)	  nd_all;	/* all existing nodes */
379 #endif	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
380 };
381 
382 /* Flags for a node */
383 #define NGF_INVALID	0x00000001	/* free when refs go to 0 */
384 #define NG_INVALID	NGF_INVALID	/* compat for old code */
385 #define NGF_FORCE_WRITER	0x00000004	/* Never multithread this node */
386 #define NG_FORCE_WRITER	NGF_FORCE_WRITER /* compat for old code */
387 #define NGF_CLOSING	0x00000008	/* ng_rmnode() at work */
388 #define NG_CLOSING	NGF_CLOSING	/* compat for old code */
389 #define NGF_REALLY_DIE	0x00000010	/* "persistent" node is unloading */
390 #define NG_REALLY_DIE	NGF_REALLY_DIE	/* compat for old code */
391 #define NGF_HI_STACK	0x00000020	/* node has hi stack usage */
392 #define NGF_TYPE1	0x10000000	/* reserved for type specific storage */
393 #define NGF_TYPE2	0x20000000	/* reserved for type specific storage */
394 #define NGF_TYPE3	0x40000000	/* reserved for type specific storage */
395 #define NGF_TYPE4	0x80000000	/* reserved for type specific storage */
396 
397 /*
398  * Public methods for nodes.
399  * If you can't do it with these you probably shouldn't be doing it.
400  */
401 void	ng_unref_node(node_p node); /* don't move this */
402 #define _NG_NODE_NAME(node)	((node)->nd_name + 0)
403 #define _NG_NODE_HAS_NAME(node)	((node)->nd_name[0] + 0)
404 #define _NG_NODE_ID(node)	((node)->nd_ID + 0)
405 #define	_NG_NODE_REF(node)	refcount_acquire(&(node)->nd_refs)
406 #define	_NG_NODE_UNREF(node)	ng_unref_node(node)
407 #define	_NG_NODE_SET_PRIVATE(node, val)	do {(node)->nd_private = val;} while (0)
408 #define	_NG_NODE_PRIVATE(node)	((node)->nd_private)
409 #define _NG_NODE_IS_VALID(node)	(!((node)->nd_flags & NGF_INVALID))
410 #define _NG_NODE_NOT_VALID(node)	((node)->nd_flags & NGF_INVALID)
411 #define _NG_NODE_NUMHOOKS(node)	((node)->nd_numhooks + 0) /* rvalue */
412 #define _NG_NODE_FORCE_WRITER(node)					\
413 	do{ node->nd_flags |= NGF_FORCE_WRITER; }while (0)
414 #define _NG_NODE_HI_STACK(node)						\
415 	do{ node->nd_flags |= NGF_HI_STACK; }while (0)
416 #define _NG_NODE_REALLY_DIE(node)					\
417 	do{ node->nd_flags |= (NGF_REALLY_DIE|NGF_INVALID); }while (0)
418 #define _NG_NODE_REVIVE(node) \
419 	do { node->nd_flags &= ~NGF_INVALID; } while (0)
420 /*
421  * The hook iterator.
422  * This macro will call a function of type ng_fn_eachhook for each
423  * hook attached to the node. If the function returns 0, then the
424  * iterator will stop and return a pointer to the hook that returned 0.
425  */
426 typedef	int	ng_fn_eachhook(hook_p hook, void* arg);
427 #define _NG_NODE_FOREACH_HOOK(node, fn, arg, rethook)			\
428 	do {								\
429 		hook_p _hook;						\
430 		(rethook) = NULL;					\
431 		LIST_FOREACH(_hook, &((node)->nd_hooks), hk_hooks) {	\
432 			if ((fn)(_hook, arg) == 0) {			\
433 				(rethook) = _hook;			\
434 				break;					\
435 			}						\
436 		}							\
437 	} while (0)
438 
439 #ifdef	NETGRAPH_DEBUG /*----------------------------------------------*/
440 void	dumpnode(node_p node, char *file, int line);
441 static __inline void _chknode(node_p node, char *file, int line);
442 static __inline char * _ng_node_name(node_p node, char *file, int line);
443 static __inline int _ng_node_has_name(node_p node, char *file, int line);
444 static __inline ng_ID_t _ng_node_id(node_p node, char *file, int line);
445 static __inline void _ng_node_ref(node_p node, char *file, int line);
446 static __inline void _ng_node_unref(node_p node, char *file, int line);
447 static __inline void _ng_node_set_private(node_p node, void * val,
448 							char *file, int line);
449 static __inline void * _ng_node_private(node_p node, char *file, int line);
450 static __inline int _ng_node_is_valid(node_p node, char *file, int line);
451 static __inline int _ng_node_not_valid(node_p node, char *file, int line);
452 static __inline int _ng_node_numhooks(node_p node, char *file, int line);
453 static __inline void _ng_node_force_writer(node_p node, char *file, int line);
454 static __inline hook_p _ng_node_foreach_hook(node_p node,
455 			ng_fn_eachhook *fn, void *arg, char *file, int line);
456 static __inline void _ng_node_revive(node_p node, char *file, int line);
457 
458 static __inline void
459 _chknode(node_p node, char *file, int line)
460 {
461 	if (node->nd_magic != ND_MAGIC) {
462 		printf("Accessing freed ");
463 		dumpnode(node, file, line);
464 	}
465 	node->lastline = line;
466 	node->lastfile = file;
467 }
468 
469 static __inline char *
470 _ng_node_name(node_p node, char *file, int line)
471 {
472 	_chknode(node, file, line);
473 	return(_NG_NODE_NAME(node));
474 }
475 
476 static __inline int
477 _ng_node_has_name(node_p node, char *file, int line)
478 {
479 	_chknode(node, file, line);
480 	return(_NG_NODE_HAS_NAME(node));
481 }
482 
483 static __inline ng_ID_t
484 _ng_node_id(node_p node, char *file, int line)
485 {
486 	_chknode(node, file, line);
487 	return(_NG_NODE_ID(node));
488 }
489 
490 static __inline void
491 _ng_node_ref(node_p node, char *file, int line)
492 {
493 	_chknode(node, file, line);
494 	_NG_NODE_REF(node);
495 }
496 
497 static __inline void
498 _ng_node_unref(node_p node, char *file, int line)
499 {
500 	_chknode(node, file, line);
501 	_NG_NODE_UNREF(node);
502 }
503 
504 static __inline void
505 _ng_node_set_private(node_p node, void * val, char *file, int line)
506 {
507 	_chknode(node, file, line);
508 	_NG_NODE_SET_PRIVATE(node, val);
509 }
510 
511 static __inline void *
512 _ng_node_private(node_p node, char *file, int line)
513 {
514 	_chknode(node, file, line);
515 	return (_NG_NODE_PRIVATE(node));
516 }
517 
518 static __inline int
519 _ng_node_is_valid(node_p node, char *file, int line)
520 {
521 	_chknode(node, file, line);
522 	return(_NG_NODE_IS_VALID(node));
523 }
524 
525 static __inline int
526 _ng_node_not_valid(node_p node, char *file, int line)
527 {
528 	_chknode(node, file, line);
529 	return(_NG_NODE_NOT_VALID(node));
530 }
531 
532 static __inline int
533 _ng_node_numhooks(node_p node, char *file, int line)
534 {
535 	_chknode(node, file, line);
536 	return(_NG_NODE_NUMHOOKS(node));
537 }
538 
539 static __inline void
540 _ng_node_force_writer(node_p node, char *file, int line)
541 {
542 	_chknode(node, file, line);
543 	_NG_NODE_FORCE_WRITER(node);
544 }
545 
546 static __inline void
547 _ng_node_hi_stack(node_p node, char *file, int line)
548 {
549 	_chknode(node, file, line);
550 	_NG_NODE_HI_STACK(node);
551 }
552 
553 static __inline void
554 _ng_node_really_die(node_p node, char *file, int line)
555 {
556 	_chknode(node, file, line);
557 	_NG_NODE_REALLY_DIE(node);
558 }
559 
560 static __inline void
561 _ng_node_revive(node_p node, char *file, int line)
562 {
563 	_chknode(node, file, line);
564 	_NG_NODE_REVIVE(node);
565 }
566 
567 static __inline hook_p
568 _ng_node_foreach_hook(node_p node, ng_fn_eachhook *fn, void *arg,
569 						char *file, int line)
570 {
571 	hook_p hook;
572 	_chknode(node, file, line);
573 	_NG_NODE_FOREACH_HOOK(node, fn, arg, hook);
574 	return (hook);
575 }
576 
577 #define NG_NODE_NAME(node)		_ng_node_name(node, _NN_)
578 #define NG_NODE_HAS_NAME(node)		_ng_node_has_name(node, _NN_)
579 #define NG_NODE_ID(node)		_ng_node_id(node, _NN_)
580 #define NG_NODE_REF(node)		_ng_node_ref(node, _NN_)
581 #define	NG_NODE_UNREF(node)		_ng_node_unref(node, _NN_)
582 #define	NG_NODE_SET_PRIVATE(node, val)	_ng_node_set_private(node, val, _NN_)
583 #define	NG_NODE_PRIVATE(node)		_ng_node_private(node, _NN_)
584 #define NG_NODE_IS_VALID(node)		_ng_node_is_valid(node, _NN_)
585 #define NG_NODE_NOT_VALID(node)		_ng_node_not_valid(node, _NN_)
586 #define NG_NODE_FORCE_WRITER(node) 	_ng_node_force_writer(node, _NN_)
587 #define NG_NODE_HI_STACK(node) 		_ng_node_hi_stack(node, _NN_)
588 #define NG_NODE_REALLY_DIE(node) 	_ng_node_really_die(node, _NN_)
589 #define NG_NODE_NUMHOOKS(node)		_ng_node_numhooks(node, _NN_)
590 #define NG_NODE_REVIVE(node)		_ng_node_revive(node, _NN_)
591 #define NG_NODE_FOREACH_HOOK(node, fn, arg, rethook)			      \
592 	do {								      \
593 		rethook = _ng_node_foreach_hook(node, fn, (void *)arg, _NN_); \
594 	} while (0)
595 
596 #else	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
597 
598 #define NG_NODE_NAME(node)		_NG_NODE_NAME(node)
599 #define NG_NODE_HAS_NAME(node)		_NG_NODE_HAS_NAME(node)
600 #define NG_NODE_ID(node)		_NG_NODE_ID(node)
601 #define	NG_NODE_REF(node)		_NG_NODE_REF(node)
602 #define	NG_NODE_UNREF(node)		_NG_NODE_UNREF(node)
603 #define	NG_NODE_SET_PRIVATE(node, val)	_NG_NODE_SET_PRIVATE(node, val)
604 #define	NG_NODE_PRIVATE(node)		_NG_NODE_PRIVATE(node)
605 #define NG_NODE_IS_VALID(node)		_NG_NODE_IS_VALID(node)
606 #define NG_NODE_NOT_VALID(node)		_NG_NODE_NOT_VALID(node)
607 #define NG_NODE_FORCE_WRITER(node) 	_NG_NODE_FORCE_WRITER(node)
608 #define NG_NODE_HI_STACK(node) 		_NG_NODE_HI_STACK(node)
609 #define NG_NODE_REALLY_DIE(node) 	_NG_NODE_REALLY_DIE(node)
610 #define NG_NODE_NUMHOOKS(node)		_NG_NODE_NUMHOOKS(node)
611 #define NG_NODE_REVIVE(node)		_NG_NODE_REVIVE(node)
612 #define NG_NODE_FOREACH_HOOK(node, fn, arg, rethook)			\
613 		_NG_NODE_FOREACH_HOOK(node, fn, arg, rethook)
614 #endif	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
615 
616 /***********************************************************************
617  ************* Node Queue and Item Structures and Methods **************
618  ***********************************************************************
619  *
620  */
621 typedef	void	ng_item_fn(node_p node, hook_p hook, void *arg1, int arg2);
622 typedef	int	ng_item_fn2(node_p node, struct ng_item *item, hook_p hook);
623 typedef	void	ng_apply_t(void *context, int error);
624 struct ng_apply_info {
625 	ng_apply_t	*apply;
626 	void		*context;
627 	int		refs;
628 	int		error;
629 };
630 struct ng_item {
631 	u_long	el_flags;
632 	STAILQ_ENTRY(ng_item)	el_next;
633 	node_p	el_dest; /* The node it will be applied against (or NULL) */
634 	hook_p	el_hook; /* Entering hook. Optional in Control messages */
635 	union {
636 		struct mbuf	*da_m;
637 		struct {
638 			struct ng_mesg	*msg_msg;
639 			ng_ID_t		msg_retaddr;
640 		} msg;
641 		struct {
642 			union {
643 				ng_item_fn	*fn_fn;
644 				ng_item_fn2	*fn_fn2;
645 			} fn_fn;
646 			void 		*fn_arg1;
647 			int		fn_arg2;
648 		} fn;
649 	} body;
650 	/*
651 	 * Optional callback called when item is being applied,
652 	 * and its context.
653 	 */
654 	struct ng_apply_info	*apply;
655 	u_int	depth;
656 #ifdef	NETGRAPH_DEBUG /*----------------------------------------------*/
657 	char *lastfile;
658 	int  lastline;
659 	TAILQ_ENTRY(ng_item)	  all;		/* all existing items */
660 #endif	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
661 };
662 
663 #define NGQF_TYPE	0x03		/* MASK of content definition */
664 #define NGQF_MESG	0x00		/* the queue element is a message */
665 #define NGQF_DATA	0x01		/* the queue element is data */
666 #define NGQF_FN		0x02		/* the queue element is a function */
667 #define NGQF_FN2	0x03		/* the queue element is a new function */
668 
669 #define NGQF_RW		0x04		/* MASK for wanted queue mode */
670 #define NGQF_READER	0x04		/* wants to be a reader */
671 #define NGQF_WRITER	0x00		/* wants to be a writer */
672 
673 #define NGQF_QMODE	0x08		/* MASK for how it was queued */
674 #define NGQF_QREADER	0x08		/* was queued as a reader */
675 #define NGQF_QWRITER	0x00		/* was queued as a writer */
676 
677 /*
678  * Get the mbuf (etc) out of an item.
679  * Sets the value in the item to NULL in case we need to call NG_FREE_ITEM()
680  * with it, (to avoid freeing the things twice).
681  * If you don't want to zero out the item then realise that the
682  * item still owns it.
683  * Retaddr is different. There are no references on that. It's just a number.
684  * The debug versions must be either all used everywhere or not at all.
685  */
686 
687 #define _NGI_M(i) ((i)->body.da_m)
688 #define _NGI_MSG(i) ((i)->body.msg.msg_msg)
689 #define _NGI_RETADDR(i) ((i)->body.msg.msg_retaddr)
690 #define	_NGI_FN(i) ((i)->body.fn.fn_fn.fn_fn)
691 #define	_NGI_FN2(i) ((i)->body.fn.fn_fn.fn_fn2)
692 #define	_NGI_ARG1(i) ((i)->body.fn.fn_arg1)
693 #define	_NGI_ARG2(i) ((i)->body.fn.fn_arg2)
694 #define	_NGI_NODE(i) ((i)->el_dest)
695 #define	_NGI_HOOK(i) ((i)->el_hook)
696 #define	_NGI_SET_HOOK(i,h) do { _NGI_HOOK(i) = h; h = NULL;} while (0)
697 #define	_NGI_CLR_HOOK(i)   do {						\
698 		hook_p _hook = _NGI_HOOK(i);				\
699 		if (_hook) {						\
700 			_NG_HOOK_UNREF(_hook);				\
701 			_NGI_HOOK(i) = NULL;				\
702 		}							\
703 	} while (0)
704 #define	_NGI_SET_NODE(i,n) do { _NGI_NODE(i) = n; n = NULL;} while (0)
705 #define	_NGI_CLR_NODE(i)   do {						\
706 		node_p _node = _NGI_NODE(i);				\
707 		if (_node) {						\
708 			_NG_NODE_UNREF(_node);				\
709 			_NGI_NODE(i) = NULL;				\
710 		}							\
711 	} while (0)
712 
713 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/
714 void				dumpitem(item_p item, char *file, int line);
715 static __inline void		_ngi_check(item_p item, char *file, int line) ;
716 static __inline struct mbuf **	_ngi_m(item_p item, char *file, int line) ;
717 static __inline ng_ID_t *	_ngi_retaddr(item_p item, char *file, int line);
718 static __inline struct ng_mesg ** _ngi_msg(item_p item, char *file, int line) ;
719 static __inline ng_item_fn **	_ngi_fn(item_p item, char *file, int line) ;
720 static __inline ng_item_fn2 **	_ngi_fn2(item_p item, char *file, int line) ;
721 static __inline void **		_ngi_arg1(item_p item, char *file, int line) ;
722 static __inline int *		_ngi_arg2(item_p item, char *file, int line) ;
723 static __inline node_p		_ngi_node(item_p item, char *file, int line);
724 static __inline hook_p		_ngi_hook(item_p item, char *file, int line);
725 
726 static __inline void
727 _ngi_check(item_p item, char *file, int line)
728 {
729 	(item)->lastline = line;
730 	(item)->lastfile = file;
731 }
732 
733 static __inline struct mbuf **
734 _ngi_m(item_p item, char *file, int line)
735 {
736 	_ngi_check(item, file, line);
737 	return (&_NGI_M(item));
738 }
739 
740 static __inline struct ng_mesg **
741 _ngi_msg(item_p item, char *file, int line)
742 {
743 	_ngi_check(item, file, line);
744 	return (&_NGI_MSG(item));
745 }
746 
747 static __inline ng_ID_t *
748 _ngi_retaddr(item_p item, char *file, int line)
749 {
750 	_ngi_check(item, file, line);
751 	return (&_NGI_RETADDR(item));
752 }
753 
754 static __inline ng_item_fn **
755 _ngi_fn(item_p item, char *file, int line)
756 {
757 	_ngi_check(item, file, line);
758 	return (&_NGI_FN(item));
759 }
760 
761 static __inline ng_item_fn2 **
762 _ngi_fn2(item_p item, char *file, int line)
763 {
764 	_ngi_check(item, file, line);
765 	return (&_NGI_FN2(item));
766 }
767 
768 static __inline void **
769 _ngi_arg1(item_p item, char *file, int line)
770 {
771 	_ngi_check(item, file, line);
772 	return (&_NGI_ARG1(item));
773 }
774 
775 static __inline int *
776 _ngi_arg2(item_p item, char *file, int line)
777 {
778 	_ngi_check(item, file, line);
779 	return (&_NGI_ARG2(item));
780 }
781 
782 static __inline node_p
783 _ngi_node(item_p item, char *file, int line)
784 {
785 	_ngi_check(item, file, line);
786 	return (_NGI_NODE(item));
787 }
788 
789 static __inline hook_p
790 _ngi_hook(item_p item, char *file, int line)
791 {
792 	_ngi_check(item, file, line);
793 	return (_NGI_HOOK(item));
794 }
795 
796 #define NGI_M(i)	(*_ngi_m(i, _NN_))
797 #define NGI_MSG(i)	(*_ngi_msg(i, _NN_))
798 #define NGI_RETADDR(i)	(*_ngi_retaddr(i, _NN_))
799 #define NGI_FN(i)	(*_ngi_fn(i, _NN_))
800 #define NGI_FN2(i)	(*_ngi_fn2(i, _NN_))
801 #define NGI_ARG1(i)	(*_ngi_arg1(i, _NN_))
802 #define NGI_ARG2(i)	(*_ngi_arg2(i, _NN_))
803 #define NGI_HOOK(i)	_ngi_hook(i, _NN_)
804 #define NGI_NODE(i)	_ngi_node(i, _NN_)
805 #define	NGI_SET_HOOK(i,h)						\
806 	do { _ngi_check(i, _NN_); _NGI_SET_HOOK(i, h); } while (0)
807 #define	NGI_CLR_HOOK(i)							\
808 	do { _ngi_check(i, _NN_); _NGI_CLR_HOOK(i); } while (0)
809 #define	NGI_SET_NODE(i,n)						\
810 	do { _ngi_check(i, _NN_); _NGI_SET_NODE(i, n); } while (0)
811 #define	NGI_CLR_NODE(i)							\
812 	do { _ngi_check(i, _NN_); _NGI_CLR_NODE(i); } while (0)
813 
814 #define NG_FREE_ITEM(item)						\
815 	do {								\
816 		_ngi_check(item, _NN_);					\
817 		ng_free_item((item));					\
818 	} while (0)
819 
820 #define	SAVE_LINE(item)							\
821 	do {								\
822 		(item)->lastline = __LINE__;				\
823 		(item)->lastfile = __FILE__;				\
824 	} while (0)
825 
826 #else	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
827 
828 #define NGI_M(i)	_NGI_M(i)
829 #define NGI_MSG(i)	_NGI_MSG(i)
830 #define NGI_RETADDR(i)	_NGI_RETADDR(i)
831 #define NGI_FN(i)	_NGI_FN(i)
832 #define NGI_FN2(i)	_NGI_FN2(i)
833 #define NGI_ARG1(i)	_NGI_ARG1(i)
834 #define NGI_ARG2(i)	_NGI_ARG2(i)
835 #define	NGI_NODE(i)	_NGI_NODE(i)
836 #define	NGI_HOOK(i)	_NGI_HOOK(i)
837 #define	NGI_SET_HOOK(i,h) _NGI_SET_HOOK(i,h)
838 #define	NGI_CLR_HOOK(i)	  _NGI_CLR_HOOK(i)
839 #define	NGI_SET_NODE(i,n) _NGI_SET_NODE(i,n)
840 #define	NGI_CLR_NODE(i)	  _NGI_CLR_NODE(i)
841 
842 #define	NG_FREE_ITEM(item)	ng_free_item((item))
843 #define	SAVE_LINE(item)		do {} while (0)
844 
845 #endif	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
846 
847 #define NGI_GET_M(i,m)							\
848 	do {								\
849 		(m) = NGI_M(i);						\
850 		_NGI_M(i) = NULL;					\
851 	} while (0)
852 
853 #define NGI_GET_MSG(i,m)						\
854 	do {								\
855 		(m) = NGI_MSG(i);					\
856 		_NGI_MSG(i) = NULL;					\
857 	} while (0)
858 
859 #define NGI_GET_NODE(i,n)	/* YOU NOW HAVE THE REFERENCE */	\
860 	do {								\
861 		(n) = NGI_NODE(i);					\
862 		_NGI_NODE(i) = NULL;					\
863 	} while (0)
864 
865 #define NGI_GET_HOOK(i,h)						\
866 	do {								\
867 		(h) = NGI_HOOK(i);					\
868 		_NGI_HOOK(i) = NULL;					\
869 	} while (0)
870 
871 #define NGI_SET_WRITER(i)	((i)->el_flags &= ~NGQF_QMODE)
872 #define NGI_SET_READER(i)	((i)->el_flags |= NGQF_QREADER)
873 
874 #define NGI_QUEUED_READER(i)	((i)->el_flags & NGQF_QREADER)
875 #define NGI_QUEUED_WRITER(i)	(((i)->el_flags & NGQF_QMODE) == NGQF_QWRITER)
876 
877 /**********************************************************************
878 * Data macros.  Send, manipulate and free.
879 **********************************************************************/
880 /*
881  * Assuming the data is already ok, just set the new address and send
882  */
883 #define NG_FWD_ITEM_HOOK_FLAGS(error, item, hook, flags)		\
884 	do {								\
885 		(error) =						\
886 		    ng_address_hook(NULL, (item), (hook), NG_NOFLAGS);	\
887 		if (error == 0) {					\
888 			SAVE_LINE(item);				\
889 			(error) = ng_snd_item((item), (flags));		\
890 		}							\
891 		(item) = NULL;						\
892 	} while (0)
893 #define	NG_FWD_ITEM_HOOK(error, item, hook)	\
894 		NG_FWD_ITEM_HOOK_FLAGS(error, item, hook, NG_NOFLAGS)
895 
896 /*
897  * Forward a data packet. Mbuf pointer is updated to new value. We
898  * presume you dealt with the old one when you update it to the new one
899  * (or it maybe the old one). We got a packet and possibly had to modify
900  * the mbuf. You should probably use NGI_GET_M() if you are going to use
901  * this too.
902  */
903 #define NG_FWD_NEW_DATA_FLAGS(error, item, hook, m, flags)		\
904 	do {								\
905 		NGI_M(item) = (m);					\
906 		(m) = NULL;						\
907 		NG_FWD_ITEM_HOOK_FLAGS(error, item, hook, flags);	\
908 	} while (0)
909 #define	NG_FWD_NEW_DATA(error, item, hook, m)	\
910 		NG_FWD_NEW_DATA_FLAGS(error, item, hook, m, NG_NOFLAGS)
911 
912 /* Send a previously unpackaged mbuf. XXX: This should be called
913  * NG_SEND_DATA in future, but this name is kept for compatibility
914  * reasons.
915  */
916 #define NG_SEND_DATA_FLAGS(error, hook, m, flags)			\
917 	do {								\
918 		item_p _item;						\
919 		if ((_item = ng_package_data((m), flags))) {		\
920 			NG_FWD_ITEM_HOOK_FLAGS(error, _item, hook, flags);\
921 		} else {						\
922 			(error) = ENOMEM;				\
923 		}							\
924 		(m) = NULL;						\
925 	} while (0)
926 
927 #define NG_SEND_DATA_ONLY(error, hook, m)	\
928 		NG_SEND_DATA_FLAGS(error, hook, m, NG_NOFLAGS)
929 /* NG_SEND_DATA() compat for meta-data times */
930 #define	NG_SEND_DATA(error, hook, m, x)	\
931 		NG_SEND_DATA_FLAGS(error, hook, m, NG_NOFLAGS)
932 
933 #define NG_FREE_MSG(msg)						\
934 	do {								\
935 		if ((msg)) {						\
936 			free((msg), M_NETGRAPH_MSG);			\
937 			(msg) = NULL;					\
938 		}	 						\
939 	} while (0)
940 
941 #define NG_FREE_M(m)							\
942 	do {								\
943 		if ((m)) {						\
944 			m_freem((m));					\
945 			(m) = NULL;					\
946 		}							\
947 	} while (0)
948 
949 /*****************************************
950 * Message macros
951 *****************************************/
952 
953 #define NG_SEND_MSG_HOOK(error, here, msg, hook, retaddr)		\
954 	do {								\
955 		item_p _item;						\
956 		if ((_item = ng_package_msg(msg, NG_NOFLAGS)) == NULL) {\
957 			(msg) = NULL;					\
958 			(error) = ENOMEM;				\
959 			break;						\
960 		}							\
961 		if (((error) = ng_address_hook((here), (_item),		\
962 					(hook), (retaddr))) == 0) {	\
963 			SAVE_LINE(_item);				\
964 			(error) = ng_snd_item((_item), 0);		\
965 		}							\
966 		(msg) = NULL;						\
967 	} while (0)
968 
969 #define NG_SEND_MSG_PATH(error, here, msg, path, retaddr)		\
970 	do {								\
971 		item_p _item;						\
972 		if ((_item = ng_package_msg(msg, NG_NOFLAGS)) == NULL) {\
973 			(msg) = NULL;					\
974 			(error) = ENOMEM;				\
975 			break;						\
976 		}							\
977 		if (((error) = ng_address_path((here), (_item),		\
978 					(path), (retaddr))) == 0) {	\
979 			SAVE_LINE(_item);				\
980 			(error) = ng_snd_item((_item), 0);		\
981 		}							\
982 		(msg) = NULL;						\
983 	} while (0)
984 
985 #define NG_SEND_MSG_ID(error, here, msg, ID, retaddr)			\
986 	do {								\
987 		item_p _item;						\
988 		if ((_item = ng_package_msg(msg, NG_NOFLAGS)) == NULL) {\
989 			(msg) = NULL;					\
990 			(error) = ENOMEM;				\
991 			break;						\
992 		}							\
993 		if (((error) = ng_address_ID((here), (_item),		\
994 					(ID), (retaddr))) == 0) {	\
995 			SAVE_LINE(_item);				\
996 			(error) = ng_snd_item((_item), 0);		\
997 		}							\
998 		(msg) = NULL;						\
999 	} while (0)
1000 
1001 /*
1002  * Redirect the message to the next hop using the given hook.
1003  * ng_retarget_msg() frees the item if there is an error
1004  * and returns an error code.  It returns 0 on success.
1005  */
1006 #define NG_FWD_MSG_HOOK(error, here, item, hook, retaddr)		\
1007 	do {								\
1008 		if (((error) = ng_address_hook((here), (item),		\
1009 					(hook), (retaddr))) == 0) {	\
1010 			SAVE_LINE(item);				\
1011 			(error) = ng_snd_item((item), 0);		\
1012 		}							\
1013 		(item) = NULL;						\
1014 	} while (0)
1015 
1016 /*
1017  * Send a queue item back to it's originator with a response message.
1018  * Assume original message was removed and freed separatly.
1019  */
1020 #define NG_RESPOND_MSG(error, here, item, resp)				\
1021 	do {								\
1022 		if (resp) {						\
1023 			ng_ID_t _dest = NGI_RETADDR(item);		\
1024 			NGI_RETADDR(item) = 0;				\
1025 			NGI_MSG(item) = resp;				\
1026 			if ((error = ng_address_ID((here), (item),	\
1027 					_dest, 0)) == 0) {		\
1028 				SAVE_LINE(item);			\
1029 				(error) = ng_snd_item((item), NG_QUEUE);\
1030 			}						\
1031 		} else							\
1032 			NG_FREE_ITEM(item);				\
1033 		(item) = NULL;						\
1034 	} while (0)
1035 
1036 
1037 /***********************************************************************
1038  ******** Structures Definitions and Macros for defining a node  *******
1039  ***********************************************************************
1040  *
1041  * Here we define the structures needed to actually define a new node
1042  * type.
1043  */
1044 
1045 /*
1046  * Command list -- each node type specifies the command that it knows
1047  * how to convert between ASCII and binary using an array of these.
1048  * The last element in the array must be a terminator with cookie=0.
1049  */
1050 
1051 struct ng_cmdlist {
1052 	u_int32_t			cookie;		/* command typecookie */
1053 	int				cmd;		/* command number */
1054 	const char			*name;		/* command name */
1055 	const struct ng_parse_type	*mesgType;	/* args if !NGF_RESP */
1056 	const struct ng_parse_type	*respType;	/* args if NGF_RESP */
1057 };
1058 
1059 /*
1060  * Structure of a node type
1061  * If data is sent to the "rcvdata()" entrypoint then the system
1062  * may decide to defer it until later by queing it with the normal netgraph
1063  * input queuing system.  This is decidde by the HK_QUEUE flag being set in
1064  * the flags word of the peer (receiving) hook. The dequeuing mechanism will
1065  * ensure it is not requeued again.
1066  * Note the input queueing system is to allow modules
1067  * to 'release the stack' or to pass data across spl layers.
1068  * The data will be redelivered as soon as the NETISR code runs
1069  * which may be almost immediatly.  A node may also do it's own queueing
1070  * for other reasons (e.g. device output queuing).
1071  */
1072 struct ng_type {
1073 
1074 	u_int32_t	version; 	/* must equal NG_API_VERSION */
1075 	const char	*name;		/* Unique type name */
1076 	modeventhand_t	mod_event;	/* Module event handler (optional) */
1077 	ng_constructor_t *constructor;	/* Node constructor */
1078 	ng_rcvmsg_t	*rcvmsg;	/* control messages come here */
1079 	ng_close_t	*close;		/* warn about forthcoming shutdown */
1080 	ng_shutdown_t	*shutdown;	/* reset, and free resources */
1081 	ng_newhook_t	*newhook;	/* first notification of new hook */
1082 	ng_findhook_t	*findhook;	/* only if you have lots of hooks */
1083 	ng_connect_t	*connect;	/* final notification of new hook */
1084 	ng_rcvdata_t	*rcvdata;	/* data comes here */
1085 	ng_disconnect_t	*disconnect;	/* notify on disconnect */
1086 
1087 	const struct	ng_cmdlist *cmdlist;	/* commands we can convert */
1088 
1089 	/* R/W data private to the base netgraph code DON'T TOUCH! */
1090 	LIST_ENTRY(ng_type) types;		/* linked list of all types */
1091 	int		    refs;		/* number of instances */
1092 };
1093 
1094 /*
1095  * Use the NETGRAPH_INIT() macro to link a node type into the
1096  * netgraph system. This works for types compiled into the kernel
1097  * as well as KLD modules. The first argument should be the type
1098  * name (eg, echo) and the second a pointer to the type struct.
1099  *
1100  * If a different link time is desired, e.g., a device driver that
1101  * needs to install its netgraph type before probing, use the
1102  * NETGRAPH_INIT_ORDERED() macro instead.  Device drivers probably
1103  * want to use SI_SUB_DRIVERS/SI_ORDER_FIRST.
1104  */
1105 
1106 #define NETGRAPH_INIT_ORDERED(typename, typestructp, sub, order)	\
1107 static moduledata_t ng_##typename##_mod = {				\
1108 	"ng_" #typename,						\
1109 	ng_mod_event,							\
1110 	(typestructp)							\
1111 };									\
1112 DECLARE_MODULE(ng_##typename, ng_##typename##_mod, sub, order);		\
1113 MODULE_DEPEND(ng_##typename, netgraph,	NG_ABI_VERSION,			\
1114 					NG_ABI_VERSION,			\
1115 					NG_ABI_VERSION)
1116 
1117 #define NETGRAPH_INIT(tn, tp)						\
1118 	NETGRAPH_INIT_ORDERED(tn, tp, SI_SUB_PSEUDO, SI_ORDER_MIDDLE)
1119 
1120 /* Special malloc() type for netgraph structs and ctrl messages */
1121 /* Only these two types should be visible to nodes */
1122 MALLOC_DECLARE(M_NETGRAPH);
1123 MALLOC_DECLARE(M_NETGRAPH_MSG);
1124 
1125 /* declare the base of the netgraph sysclt hierarchy */
1126 /* but only if this file cares about sysctls */
1127 #ifdef	SYSCTL_DECL
1128 SYSCTL_DECL(_net_graph);
1129 #endif
1130 
1131 /*
1132  * Methods that the nodes can use.
1133  * Many of these methods should usually NOT be used directly but via
1134  * Macros above.
1135  */
1136 int	ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr);
1137 int	ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr);
1138 int	ng_address_path(node_p here, item_p item, const char *address, ng_ID_t raddr);
1139 int	ng_bypass(hook_p hook1, hook_p hook2);
1140 hook_p	ng_findhook(node_p node, const char *name);
1141 struct	ng_type *ng_findtype(const char *type);
1142 int	ng_make_node_common(struct ng_type *typep, node_p *nodep);
1143 int	ng_name_node(node_p node, const char *name);
1144 node_p	ng_name2noderef(node_p node, const char *name);
1145 int	ng_newtype(struct ng_type *tp);
1146 ng_ID_t ng_node2ID(node_p node);
1147 item_p	ng_package_data(struct mbuf *m, int flags);
1148 item_p	ng_package_msg(struct ng_mesg *msg, int flags);
1149 item_p	ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg);
1150 void	ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr);
1151 int	ng_rmhook_self(hook_p hook);	/* if a node wants to kill a hook */
1152 int	ng_rmnode_self(node_p here);	/* if a node wants to suicide */
1153 int	ng_rmtype(struct ng_type *tp);
1154 int	ng_snd_item(item_p item, int queue);
1155 int 	ng_send_fn(node_p node, hook_p hook, ng_item_fn *fn, void *arg1,
1156 	int arg2);
1157 int 	ng_send_fn1(node_p node, hook_p hook, ng_item_fn *fn, void *arg1,
1158 	int arg2, int flags);
1159 int 	ng_send_fn2(node_p node, hook_p hook, item_p pitem, ng_item_fn2 *fn,
1160 	void *arg1, int arg2, int flags);
1161 int	ng_uncallout(struct callout *c, node_p node);
1162 int	ng_callout(struct callout *c, node_p node, hook_p hook, int ticks,
1163 	    ng_item_fn *fn, void * arg1, int arg2);
1164 #define	ng_callout_init(c)	callout_init(c, CALLOUT_MPSAFE)
1165 
1166 /* Flags for netgraph functions. */
1167 #define	NG_NOFLAGS	0x00000000	/* no special options */
1168 #define	NG_QUEUE	0x00000001	/* enqueue item, don't dispatch */
1169 #define	NG_WAITOK	0x00000002	/* use M_WAITOK, etc. */
1170 /* XXXGL: NG_PROGRESS unused since ng_base.c rev. 1.136. Should be deleted? */
1171 #define	NG_PROGRESS	0x00000004	/* return EINPROGRESS if queued */
1172 #define	NG_REUSE_ITEM	0x00000008	/* supplied item should be reused */
1173 
1174 /*
1175  * prototypes the user should DEFINITELY not use directly
1176  */
1177 void	ng_free_item(item_p item); /* Use NG_FREE_ITEM instead */
1178 int	ng_mod_event(module_t mod, int what, void *arg);
1179 
1180 /*
1181  * Tag definitions and constants
1182  */
1183 
1184 #define	NG_TAG_PRIO	1
1185 
1186 struct ng_tag_prio {
1187 	struct m_tag	tag;
1188 	char	priority;
1189 	char	discardability;
1190 };
1191 
1192 #define	NG_PRIO_CUTOFF		32
1193 #define	NG_PRIO_LINKSTATE	64
1194 
1195 /* Macros and declarations to keep compatibility with metadata, which
1196  * is obsoleted now. To be deleted.
1197  */
1198 typedef void *meta_p;
1199 #define _NGI_META(i)	NULL
1200 #define NGI_META(i)	NULL
1201 #define NG_FREE_META(meta)
1202 #define NGI_GET_META(i,m)
1203 #define	ng_copy_meta(meta) NULL
1204 
1205 /*
1206  * Mark the current thread when called from the outbound path of the
1207  * network stack, in order to enforce queuing on ng nodes calling into
1208  * the inbound network stack path.
1209  */
1210 #define NG_OUTBOUND_THREAD_REF()					\
1211 	curthread->td_ng_outbound++
1212 #define NG_OUTBOUND_THREAD_UNREF()					\
1213 	do {								\
1214 		curthread->td_ng_outbound--;				\
1215 		KASSERT(curthread->td_ng_outbound >= 0,			\
1216 		    ("%s: negative td_ng_outbound", __func__));		\
1217 	} while (0)
1218 
1219 #endif /* _NETGRAPH_NETGRAPH_H_ */
1220