xref: /freebsd/sys/netgraph/netgraph.h (revision a9d2f8d84f69e98100b5746816b35666bcf992ac)
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 #endif
61 
62 /* debugging options */
63 #define NG_SEPARATE_MALLOC	/* make modules use their own malloc types */
64 
65 /*
66  * This defines the in-kernel binary interface version.
67  * It is possible to change this but leave the external message
68  * API the same. Each type also has it's own cookies for versioning as well.
69  * Change it for NETGRAPH_DEBUG version so we cannot mix debug and non debug
70  * modules.
71  */
72 #define _NG_ABI_VERSION 12
73 #ifdef	NETGRAPH_DEBUG /*----------------------------------------------*/
74 #define NG_ABI_VERSION	(_NG_ABI_VERSION + 0x10000)
75 #else	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
76 #define NG_ABI_VERSION	_NG_ABI_VERSION
77 #endif	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
78 
79 
80 /*
81  * Forward references for the basic structures so we can
82  * define the typedefs and use them in the structures themselves.
83  */
84 struct ng_hook ;
85 struct ng_node ;
86 struct ng_item ;
87 typedef	struct ng_item *item_p;
88 typedef struct ng_node *node_p;
89 typedef struct ng_hook *hook_p;
90 
91 /* node method definitions */
92 typedef	int	ng_constructor_t(node_p node);
93 typedef	int	ng_close_t(node_p node);
94 typedef	int	ng_shutdown_t(node_p node);
95 typedef	int	ng_newhook_t(node_p node, hook_p hook, const char *name);
96 typedef	hook_p	ng_findhook_t(node_p node, const char *name);
97 typedef	int	ng_connect_t(hook_p hook);
98 typedef	int	ng_rcvmsg_t(node_p node, item_p item, hook_p lasthook);
99 typedef	int	ng_rcvdata_t(hook_p hook, item_p item);
100 typedef	int	ng_disconnect_t(hook_p hook);
101 typedef	int	ng_rcvitem (node_p node, hook_p hook, item_p item);
102 
103 /***********************************************************************
104  ***************** Hook Structure and Methods **************************
105  ***********************************************************************
106  *
107  * Structure of a hook
108  */
109 struct ng_hook {
110 	char	hk_name[NG_HOOKSIZ];	/* what this node knows this link as */
111 	void   *hk_private;		/* node dependant ID for this hook */
112 	int	hk_flags;		/* info about this hook/link */
113 	int	hk_type;		/* tbd: hook data link type */
114 	struct	ng_hook *hk_peer;	/* the other end of this link */
115 	struct	ng_node *hk_node;	/* The node this hook is attached to */
116 	LIST_ENTRY(ng_hook) hk_hooks;	/* linked list of all hooks on node */
117 	ng_rcvmsg_t	*hk_rcvmsg;	/* control messages come here */
118 	ng_rcvdata_t	*hk_rcvdata;	/* data comes here */
119 	int	hk_refs;		/* dont actually free this till 0 */
120 #ifdef	NETGRAPH_DEBUG /*----------------------------------------------*/
121 #define HK_MAGIC 0x78573011
122 	int	hk_magic;
123 	char	*lastfile;
124 	int	lastline;
125 	SLIST_ENTRY(ng_hook)	  hk_all;		/* all existing items */
126 #endif	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
127 };
128 /* Flags for a hook */
129 #define HK_INVALID		0x0001	/* don't trust it! */
130 #define HK_QUEUE		0x0002	/* queue for later delivery */
131 #define HK_FORCE_WRITER		0x0004	/* Incoming data queued as a writer */
132 #define HK_DEAD			0x0008	/* This is the dead hook.. don't free */
133 #define HK_HI_STACK		0x0010	/* Hook has hi stack usage */
134 #define HK_TO_INBOUND		0x0020	/* Hook on ntw. stack inbound path. */
135 
136 /*
137  * Public Methods for hook
138  * If you can't do it with these you probably shouldn;t be doing it.
139  */
140 void ng_unref_hook(hook_p hook); /* don't move this */
141 #define	_NG_HOOK_REF(hook)	refcount_acquire(&(hook)->hk_refs)
142 #define _NG_HOOK_NAME(hook)	((hook)->hk_name)
143 #define _NG_HOOK_UNREF(hook)	ng_unref_hook(hook)
144 #define	_NG_HOOK_SET_PRIVATE(hook, val)	do {(hook)->hk_private = val;} while (0)
145 #define	_NG_HOOK_SET_RCVMSG(hook, val)	do {(hook)->hk_rcvmsg = val;} while (0)
146 #define	_NG_HOOK_SET_RCVDATA(hook, val)	do {(hook)->hk_rcvdata = val;} while (0)
147 #define	_NG_HOOK_PRIVATE(hook)	((hook)->hk_private)
148 #define _NG_HOOK_NOT_VALID(hook)	((hook)->hk_flags & HK_INVALID)
149 #define _NG_HOOK_IS_VALID(hook)	(!((hook)->hk_flags & HK_INVALID))
150 #define _NG_HOOK_NODE(hook)	((hook)->hk_node) /* only rvalue! */
151 #define _NG_HOOK_PEER(hook)	((hook)->hk_peer) /* only rvalue! */
152 #define _NG_HOOK_FORCE_WRITER(hook)				\
153 		do { hook->hk_flags |= HK_FORCE_WRITER; } while (0)
154 #define _NG_HOOK_FORCE_QUEUE(hook) do { hook->hk_flags |= HK_QUEUE; } while (0)
155 #define _NG_HOOK_SET_TO_INBOUND(hook)				\
156 		do { hook->hk_flags |= HK_TO_INBOUND; } while (0)
157 #define _NG_HOOK_HI_STACK(hook) do { hook->hk_flags |= HK_HI_STACK; } while (0)
158 
159 /* Some shortcuts */
160 #define NG_PEER_NODE(hook)	NG_HOOK_NODE(NG_HOOK_PEER(hook))
161 #define NG_PEER_HOOK_NAME(hook)	NG_HOOK_NAME(NG_HOOK_PEER(hook))
162 #define NG_PEER_NODE_NAME(hook)	NG_NODE_NAME(NG_PEER_NODE(hook))
163 
164 #ifdef	NETGRAPH_DEBUG /*----------------------------------------------*/
165 #define _NN_ __FILE__,__LINE__
166 void	dumphook (hook_p hook, char *file, int line);
167 static __inline void	_chkhook(hook_p hook, char *file, int line);
168 static __inline void	_ng_hook_ref(hook_p hook, char * file, int line);
169 static __inline char *	_ng_hook_name(hook_p hook, char * file, int line);
170 static __inline void	_ng_hook_unref(hook_p hook, char * file, int line);
171 static __inline void	_ng_hook_set_private(hook_p hook,
172 				void * val, char * file, int line);
173 static __inline void	_ng_hook_set_rcvmsg(hook_p hook,
174 				ng_rcvmsg_t *val, char * file, int line);
175 static __inline void	_ng_hook_set_rcvdata(hook_p hook,
176 				ng_rcvdata_t *val, char * file, int line);
177 static __inline void *	_ng_hook_private(hook_p hook, char * file, int line);
178 static __inline int	_ng_hook_not_valid(hook_p hook, char * file, int line);
179 static __inline int	_ng_hook_is_valid(hook_p hook, char * file, int line);
180 static __inline node_p	_ng_hook_node(hook_p hook, char * file, int line);
181 static __inline hook_p	_ng_hook_peer(hook_p hook, char * file, int line);
182 static __inline void	_ng_hook_force_writer(hook_p hook, char * file,
183 				int line);
184 static __inline void	_ng_hook_force_queue(hook_p hook, char * file,
185 				int line);
186 static __inline void	_ng_hook_set_to_inbound(hook_p hook, char * file,
187 				int line);
188 
189 static __inline void
190 _chkhook(hook_p hook, char *file, int line)
191 {
192 	if (hook->hk_magic != HK_MAGIC) {
193 		printf("Accessing freed hook ");
194 		dumphook(hook, file, line);
195 	}
196 	hook->lastline = line;
197 	hook->lastfile = file;
198 }
199 
200 static __inline void
201 _ng_hook_ref(hook_p hook, char * file, int line)
202 {
203 	_chkhook(hook, file, line);
204 	_NG_HOOK_REF(hook);
205 }
206 
207 static __inline char *
208 _ng_hook_name(hook_p hook, char * file, int line)
209 {
210 	_chkhook(hook, file, line);
211 	return (_NG_HOOK_NAME(hook));
212 }
213 
214 static __inline void
215 _ng_hook_unref(hook_p hook, char * file, int line)
216 {
217 	_chkhook(hook, file, line);
218 	_NG_HOOK_UNREF(hook);
219 }
220 
221 static __inline void
222 _ng_hook_set_private(hook_p hook, void *val, char * file, int line)
223 {
224 	_chkhook(hook, file, line);
225 	_NG_HOOK_SET_PRIVATE(hook, val);
226 }
227 
228 static __inline void
229 _ng_hook_set_rcvmsg(hook_p hook, ng_rcvmsg_t *val, char * file, int line)
230 {
231 	_chkhook(hook, file, line);
232 	_NG_HOOK_SET_RCVMSG(hook, val);
233 }
234 
235 static __inline void
236 _ng_hook_set_rcvdata(hook_p hook, ng_rcvdata_t *val, char * file, int line)
237 {
238 	_chkhook(hook, file, line);
239 	_NG_HOOK_SET_RCVDATA(hook, val);
240 }
241 
242 static __inline void *
243 _ng_hook_private(hook_p hook, char * file, int line)
244 {
245 	_chkhook(hook, file, line);
246 	return (_NG_HOOK_PRIVATE(hook));
247 }
248 
249 static __inline int
250 _ng_hook_not_valid(hook_p hook, char * file, int line)
251 {
252 	_chkhook(hook, file, line);
253 	return (_NG_HOOK_NOT_VALID(hook));
254 }
255 
256 static __inline int
257 _ng_hook_is_valid(hook_p hook, char * file, int line)
258 {
259 	_chkhook(hook, file, line);
260 	return (_NG_HOOK_IS_VALID(hook));
261 }
262 
263 static __inline node_p
264 _ng_hook_node(hook_p hook, char * file, int line)
265 {
266 	_chkhook(hook, file, line);
267 	return (_NG_HOOK_NODE(hook));
268 }
269 
270 static __inline hook_p
271 _ng_hook_peer(hook_p hook, char * file, int line)
272 {
273 	_chkhook(hook, file, line);
274 	return (_NG_HOOK_PEER(hook));
275 }
276 
277 static __inline void
278 _ng_hook_force_writer(hook_p hook, char * file, int line)
279 {
280 	_chkhook(hook, file, line);
281 	_NG_HOOK_FORCE_WRITER(hook);
282 }
283 
284 static __inline void
285 _ng_hook_force_queue(hook_p hook, char * file, int line)
286 {
287 	_chkhook(hook, file, line);
288 	_NG_HOOK_FORCE_QUEUE(hook);
289 }
290 
291 static __inline void
292 _ng_hook_set_to_inbound(hook_p hook, char * file, int line)
293 {
294 	_chkhook(hook, file, line);
295 	_NG_HOOK_SET_TO_INBOUND(hook);
296 }
297 
298 static __inline void
299 _ng_hook_hi_stack(hook_p hook, char * file, int line)
300 {
301 	_chkhook(hook, file, line);
302 	_NG_HOOK_HI_STACK(hook);
303 }
304 
305 
306 #define	NG_HOOK_REF(hook)		_ng_hook_ref(hook, _NN_)
307 #define NG_HOOK_NAME(hook)		_ng_hook_name(hook, _NN_)
308 #define NG_HOOK_UNREF(hook)		_ng_hook_unref(hook, _NN_)
309 #define	NG_HOOK_SET_PRIVATE(hook, val)	_ng_hook_set_private(hook, val, _NN_)
310 #define	NG_HOOK_SET_RCVMSG(hook, val)	_ng_hook_set_rcvmsg(hook, val, _NN_)
311 #define	NG_HOOK_SET_RCVDATA(hook, val)	_ng_hook_set_rcvdata(hook, val, _NN_)
312 #define	NG_HOOK_PRIVATE(hook)		_ng_hook_private(hook, _NN_)
313 #define NG_HOOK_NOT_VALID(hook)		_ng_hook_not_valid(hook, _NN_)
314 #define NG_HOOK_IS_VALID(hook)		_ng_hook_is_valid(hook, _NN_)
315 #define NG_HOOK_NODE(hook)		_ng_hook_node(hook, _NN_)
316 #define NG_HOOK_PEER(hook)		_ng_hook_peer(hook, _NN_)
317 #define NG_HOOK_FORCE_WRITER(hook)	_ng_hook_force_writer(hook, _NN_)
318 #define NG_HOOK_FORCE_QUEUE(hook)	_ng_hook_force_queue(hook, _NN_)
319 #define NG_HOOK_SET_TO_INBOUND(hook)	_ng_hook_set_to_inbound(hook, _NN_)
320 #define NG_HOOK_HI_STACK(hook)		_ng_hook_hi_stack(hook, _NN_)
321 
322 #else	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
323 
324 #define	NG_HOOK_REF(hook)		_NG_HOOK_REF(hook)
325 #define NG_HOOK_NAME(hook)		_NG_HOOK_NAME(hook)
326 #define NG_HOOK_UNREF(hook)		_NG_HOOK_UNREF(hook)
327 #define	NG_HOOK_SET_PRIVATE(hook, val)	_NG_HOOK_SET_PRIVATE(hook, val)
328 #define	NG_HOOK_SET_RCVMSG(hook, val)	_NG_HOOK_SET_RCVMSG(hook, val)
329 #define	NG_HOOK_SET_RCVDATA(hook, val)	_NG_HOOK_SET_RCVDATA(hook, val)
330 #define	NG_HOOK_PRIVATE(hook)		_NG_HOOK_PRIVATE(hook)
331 #define NG_HOOK_NOT_VALID(hook)		_NG_HOOK_NOT_VALID(hook)
332 #define NG_HOOK_IS_VALID(hook)		_NG_HOOK_IS_VALID(hook)
333 #define NG_HOOK_NODE(hook)		_NG_HOOK_NODE(hook)
334 #define NG_HOOK_PEER(hook)		_NG_HOOK_PEER(hook)
335 #define NG_HOOK_FORCE_WRITER(hook)	_NG_HOOK_FORCE_WRITER(hook)
336 #define NG_HOOK_FORCE_QUEUE(hook)	_NG_HOOK_FORCE_QUEUE(hook)
337 #define NG_HOOK_SET_TO_INBOUND(hook)	_NG_HOOK_SET_TO_INBOUND(hook)
338 #define NG_HOOK_HI_STACK(hook)		_NG_HOOK_HI_STACK(hook)
339 
340 #endif	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
341 
342 /***********************************************************************
343  ***************** Node Structure and Methods **************************
344  ***********************************************************************
345  * Structure of a node
346  * including the eembedded queue structure.
347  *
348  * The structure for queueing Netgraph request items
349  * embedded in the node structure
350  */
351 struct ng_queue {
352 	u_int		q_flags;	/* Current r/w/q lock flags */
353 	u_int		q_flags2;	/* Other queue flags */
354 	struct mtx	q_mtx;
355 	STAILQ_ENTRY(ng_node)	q_work;	/* nodes with work to do */
356 	STAILQ_HEAD(, ng_item)	queue;	/* actually items queue */
357 };
358 
359 struct ng_node {
360 	char	nd_name[NG_NODESIZ];	/* optional globally unique name */
361 	struct	ng_type *nd_type;	/* the installed 'type' */
362 	int	nd_flags;		/* see below for bit definitions */
363 	int	nd_numhooks;		/* number of hooks */
364 	void   *nd_private;		/* node type dependant node ID */
365 	ng_ID_t	nd_ID;			/* Unique per node */
366 	LIST_HEAD(hooks, ng_hook) nd_hooks;	/* linked list of node hooks */
367 	LIST_ENTRY(ng_node)	  nd_nodes;	/* linked list of all nodes */
368 	LIST_ENTRY(ng_node)	  nd_idnodes;	/* ID hash collision list */
369 	struct	ng_queue	  nd_input_queue; /* input queue for locking */
370 	int	nd_refs;		/* # of references to this node */
371 	struct	vnet		 *nd_vnet;	/* network stack instance */
372 #ifdef	NETGRAPH_DEBUG /*----------------------------------------------*/
373 #define ND_MAGIC 0x59264837
374 	int	nd_magic;
375 	char	*lastfile;
376 	int	lastline;
377 	SLIST_ENTRY(ng_node)	  nd_all;	/* all existing nodes */
378 #endif	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
379 };
380 
381 /* Flags for a node */
382 #define NGF_INVALID	0x00000001	/* free when refs go to 0 */
383 #define NG_INVALID	NGF_INVALID	/* compat for old code */
384 #define NGF_FORCE_WRITER	0x00000004	/* Never multithread this node */
385 #define NG_FORCE_WRITER	NGF_FORCE_WRITER /* compat for old code */
386 #define NGF_CLOSING	0x00000008	/* ng_rmnode() at work */
387 #define NG_CLOSING	NGF_CLOSING	/* compat for old code */
388 #define NGF_REALLY_DIE	0x00000010	/* "persistent" node is unloading */
389 #define NG_REALLY_DIE	NGF_REALLY_DIE	/* compat for old code */
390 #define NGF_HI_STACK	0x00000020	/* node has hi stack usage */
391 #define NGF_TYPE1	0x10000000	/* reserved for type specific storage */
392 #define NGF_TYPE2	0x20000000	/* reserved for type specific storage */
393 #define NGF_TYPE3	0x40000000	/* reserved for type specific storage */
394 #define NGF_TYPE4	0x80000000	/* reserved for type specific storage */
395 
396 /*
397  * Public methods for nodes.
398  * If you can't do it with these you probably shouldn't be doing it.
399  */
400 void	ng_unref_node(node_p node); /* don't move this */
401 #define _NG_NODE_NAME(node)	((node)->nd_name + 0)
402 #define _NG_NODE_HAS_NAME(node)	((node)->nd_name[0] + 0)
403 #define _NG_NODE_ID(node)	((node)->nd_ID + 0)
404 #define	_NG_NODE_REF(node)	refcount_acquire(&(node)->nd_refs)
405 #define	_NG_NODE_UNREF(node)	ng_unref_node(node)
406 #define	_NG_NODE_SET_PRIVATE(node, val)	do {(node)->nd_private = val;} while (0)
407 #define	_NG_NODE_PRIVATE(node)	((node)->nd_private)
408 #define _NG_NODE_IS_VALID(node)	(!((node)->nd_flags & NGF_INVALID))
409 #define _NG_NODE_NOT_VALID(node)	((node)->nd_flags & NGF_INVALID)
410 #define _NG_NODE_NUMHOOKS(node)	((node)->nd_numhooks + 0) /* rvalue */
411 #define _NG_NODE_FORCE_WRITER(node)					\
412 	do{ node->nd_flags |= NGF_FORCE_WRITER; }while (0)
413 #define _NG_NODE_HI_STACK(node)						\
414 	do{ node->nd_flags |= NGF_HI_STACK; }while (0)
415 #define _NG_NODE_REALLY_DIE(node)					\
416 	do{ node->nd_flags |= (NGF_REALLY_DIE|NGF_INVALID); }while (0)
417 #define _NG_NODE_REVIVE(node) \
418 	do { node->nd_flags &= ~NGF_INVALID; } while (0)
419 /*
420  * The hook iterator.
421  * This macro will call a function of type ng_fn_eachhook for each
422  * hook attached to the node. If the function returns 0, then the
423  * iterator will stop and return a pointer to the hook that returned 0.
424  */
425 typedef	int	ng_fn_eachhook(hook_p hook, void* arg);
426 #define _NG_NODE_FOREACH_HOOK(node, fn, arg, rethook)			\
427 	do {								\
428 		hook_p _hook;						\
429 		(rethook) = NULL;					\
430 		LIST_FOREACH(_hook, &((node)->nd_hooks), hk_hooks) {	\
431 			if ((fn)(_hook, arg) == 0) {			\
432 				(rethook) = _hook;			\
433 				break;					\
434 			}						\
435 		}							\
436 	} while (0)
437 
438 #ifdef	NETGRAPH_DEBUG /*----------------------------------------------*/
439 void	dumpnode(node_p node, char *file, int line);
440 static __inline void _chknode(node_p node, char *file, int line);
441 static __inline char * _ng_node_name(node_p node, char *file, int line);
442 static __inline int _ng_node_has_name(node_p node, char *file, int line);
443 static __inline ng_ID_t _ng_node_id(node_p node, char *file, int line);
444 static __inline void _ng_node_ref(node_p node, char *file, int line);
445 static __inline void _ng_node_unref(node_p node, char *file, int line);
446 static __inline void _ng_node_set_private(node_p node, void * val,
447 							char *file, int line);
448 static __inline void * _ng_node_private(node_p node, char *file, int line);
449 static __inline int _ng_node_is_valid(node_p node, char *file, int line);
450 static __inline int _ng_node_not_valid(node_p node, char *file, int line);
451 static __inline int _ng_node_numhooks(node_p node, char *file, int line);
452 static __inline void _ng_node_force_writer(node_p node, char *file, int line);
453 static __inline hook_p _ng_node_foreach_hook(node_p node,
454 			ng_fn_eachhook *fn, void *arg, char *file, int line);
455 static __inline void _ng_node_revive(node_p node, char *file, int line);
456 
457 static __inline void
458 _chknode(node_p node, char *file, int line)
459 {
460 	if (node->nd_magic != ND_MAGIC) {
461 		printf("Accessing freed node ");
462 		dumpnode(node, file, line);
463 	}
464 	node->lastline = line;
465 	node->lastfile = file;
466 }
467 
468 static __inline char *
469 _ng_node_name(node_p node, char *file, int line)
470 {
471 	_chknode(node, file, line);
472 	return(_NG_NODE_NAME(node));
473 }
474 
475 static __inline int
476 _ng_node_has_name(node_p node, char *file, int line)
477 {
478 	_chknode(node, file, line);
479 	return(_NG_NODE_HAS_NAME(node));
480 }
481 
482 static __inline ng_ID_t
483 _ng_node_id(node_p node, char *file, int line)
484 {
485 	_chknode(node, file, line);
486 	return(_NG_NODE_ID(node));
487 }
488 
489 static __inline void
490 _ng_node_ref(node_p node, char *file, int line)
491 {
492 	_chknode(node, file, line);
493 	_NG_NODE_REF(node);
494 }
495 
496 static __inline void
497 _ng_node_unref(node_p node, char *file, int line)
498 {
499 	_chknode(node, file, line);
500 	_NG_NODE_UNREF(node);
501 }
502 
503 static __inline void
504 _ng_node_set_private(node_p node, void * val, char *file, int line)
505 {
506 	_chknode(node, file, line);
507 	_NG_NODE_SET_PRIVATE(node, val);
508 }
509 
510 static __inline void *
511 _ng_node_private(node_p node, char *file, int line)
512 {
513 	_chknode(node, file, line);
514 	return (_NG_NODE_PRIVATE(node));
515 }
516 
517 static __inline int
518 _ng_node_is_valid(node_p node, char *file, int line)
519 {
520 	_chknode(node, file, line);
521 	return(_NG_NODE_IS_VALID(node));
522 }
523 
524 static __inline int
525 _ng_node_not_valid(node_p node, char *file, int line)
526 {
527 	_chknode(node, file, line);
528 	return(_NG_NODE_NOT_VALID(node));
529 }
530 
531 static __inline int
532 _ng_node_numhooks(node_p node, char *file, int line)
533 {
534 	_chknode(node, file, line);
535 	return(_NG_NODE_NUMHOOKS(node));
536 }
537 
538 static __inline void
539 _ng_node_force_writer(node_p node, char *file, int line)
540 {
541 	_chknode(node, file, line);
542 	_NG_NODE_FORCE_WRITER(node);
543 }
544 
545 static __inline void
546 _ng_node_hi_stack(node_p node, char *file, int line)
547 {
548 	_chknode(node, file, line);
549 	_NG_NODE_HI_STACK(node);
550 }
551 
552 static __inline void
553 _ng_node_really_die(node_p node, char *file, int line)
554 {
555 	_chknode(node, file, line);
556 	_NG_NODE_REALLY_DIE(node);
557 }
558 
559 static __inline void
560 _ng_node_revive(node_p node, char *file, int line)
561 {
562 	_chknode(node, file, line);
563 	_NG_NODE_REVIVE(node);
564 }
565 
566 static __inline hook_p
567 _ng_node_foreach_hook(node_p node, ng_fn_eachhook *fn, void *arg,
568 						char *file, int line)
569 {
570 	hook_p hook;
571 	_chknode(node, file, line);
572 	_NG_NODE_FOREACH_HOOK(node, fn, arg, hook);
573 	return (hook);
574 }
575 
576 #define NG_NODE_NAME(node)		_ng_node_name(node, _NN_)
577 #define NG_NODE_HAS_NAME(node)		_ng_node_has_name(node, _NN_)
578 #define NG_NODE_ID(node)		_ng_node_id(node, _NN_)
579 #define NG_NODE_REF(node)		_ng_node_ref(node, _NN_)
580 #define	NG_NODE_UNREF(node)		_ng_node_unref(node, _NN_)
581 #define	NG_NODE_SET_PRIVATE(node, val)	_ng_node_set_private(node, val, _NN_)
582 #define	NG_NODE_PRIVATE(node)		_ng_node_private(node, _NN_)
583 #define NG_NODE_IS_VALID(node)		_ng_node_is_valid(node, _NN_)
584 #define NG_NODE_NOT_VALID(node)		_ng_node_not_valid(node, _NN_)
585 #define NG_NODE_FORCE_WRITER(node) 	_ng_node_force_writer(node, _NN_)
586 #define NG_NODE_HI_STACK(node) 		_ng_node_hi_stack(node, _NN_)
587 #define NG_NODE_REALLY_DIE(node) 	_ng_node_really_die(node, _NN_)
588 #define NG_NODE_NUMHOOKS(node)		_ng_node_numhooks(node, _NN_)
589 #define NG_NODE_REVIVE(node)		_ng_node_revive(node, _NN_)
590 #define NG_NODE_FOREACH_HOOK(node, fn, arg, rethook)			      \
591 	do {								      \
592 		rethook = _ng_node_foreach_hook(node, fn, (void *)arg, _NN_); \
593 	} while (0)
594 
595 #else	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
596 
597 #define NG_NODE_NAME(node)		_NG_NODE_NAME(node)
598 #define NG_NODE_HAS_NAME(node)		_NG_NODE_HAS_NAME(node)
599 #define NG_NODE_ID(node)		_NG_NODE_ID(node)
600 #define	NG_NODE_REF(node)		_NG_NODE_REF(node)
601 #define	NG_NODE_UNREF(node)		_NG_NODE_UNREF(node)
602 #define	NG_NODE_SET_PRIVATE(node, val)	_NG_NODE_SET_PRIVATE(node, val)
603 #define	NG_NODE_PRIVATE(node)		_NG_NODE_PRIVATE(node)
604 #define NG_NODE_IS_VALID(node)		_NG_NODE_IS_VALID(node)
605 #define NG_NODE_NOT_VALID(node)		_NG_NODE_NOT_VALID(node)
606 #define NG_NODE_FORCE_WRITER(node) 	_NG_NODE_FORCE_WRITER(node)
607 #define NG_NODE_HI_STACK(node) 		_NG_NODE_HI_STACK(node)
608 #define NG_NODE_REALLY_DIE(node) 	_NG_NODE_REALLY_DIE(node)
609 #define NG_NODE_NUMHOOKS(node)		_NG_NODE_NUMHOOKS(node)
610 #define NG_NODE_REVIVE(node)		_NG_NODE_REVIVE(node)
611 #define NG_NODE_FOREACH_HOOK(node, fn, arg, rethook)			\
612 		_NG_NODE_FOREACH_HOOK(node, fn, arg, rethook)
613 #endif	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
614 
615 /***********************************************************************
616  ************* Node Queue and Item Structures and Methods **************
617  ***********************************************************************
618  *
619  */
620 typedef	void	ng_item_fn(node_p node, hook_p hook, void *arg1, int arg2);
621 typedef	int	ng_item_fn2(node_p node, struct ng_item *item, hook_p hook);
622 typedef	void	ng_apply_t(void *context, int error);
623 struct ng_apply_info {
624 	ng_apply_t	*apply;
625 	void		*context;
626 	int		refs;
627 	int		error;
628 };
629 struct ng_item {
630 	u_long	el_flags;
631 	STAILQ_ENTRY(ng_item)	el_next;
632 	node_p	el_dest; /* The node it will be applied against (or NULL) */
633 	hook_p	el_hook; /* Entering hook. Optional in Control messages */
634 	union {
635 		struct mbuf	*da_m;
636 		struct {
637 			struct ng_mesg	*msg_msg;
638 			ng_ID_t		msg_retaddr;
639 		} msg;
640 		struct {
641 			union {
642 				ng_item_fn	*fn_fn;
643 				ng_item_fn2	*fn_fn2;
644 			} fn_fn;
645 			void 		*fn_arg1;
646 			int		fn_arg2;
647 		} fn;
648 	} body;
649 	/*
650 	 * Optional callback called when item is being applied,
651 	 * and its context.
652 	 */
653 	struct ng_apply_info	*apply;
654 	u_int	depth;
655 #ifdef	NETGRAPH_DEBUG /*----------------------------------------------*/
656 	char *lastfile;
657 	int  lastline;
658 	TAILQ_ENTRY(ng_item)	  all;		/* all existing items */
659 #endif	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
660 };
661 
662 #define NGQF_TYPE	0x03		/* MASK of content definition */
663 #define NGQF_MESG	0x00		/* the queue element is a message */
664 #define NGQF_DATA	0x01		/* the queue element is data */
665 #define NGQF_FN		0x02		/* the queue element is a function */
666 #define NGQF_FN2	0x03		/* the queue element is a new function */
667 
668 #define NGQF_RW		0x04		/* MASK for wanted queue mode */
669 #define NGQF_READER	0x04		/* wants to be a reader */
670 #define NGQF_WRITER	0x00		/* wants to be a writer */
671 
672 #define NGQF_QMODE	0x08		/* MASK for how it was queued */
673 #define NGQF_QREADER	0x08		/* was queued as a reader */
674 #define NGQF_QWRITER	0x00		/* was queued as a writer */
675 
676 /*
677  * Get the mbuf (etc) out of an item.
678  * Sets the value in the item to NULL in case we need to call NG_FREE_ITEM()
679  * with it, (to avoid freeing the things twice).
680  * If you don't want to zero out the item then realise that the
681  * item still owns it.
682  * Retaddr is different. There are no references on that. It's just a number.
683  * The debug versions must be either all used everywhere or not at all.
684  */
685 
686 #define _NGI_M(i) ((i)->body.da_m)
687 #define _NGI_MSG(i) ((i)->body.msg.msg_msg)
688 #define _NGI_RETADDR(i) ((i)->body.msg.msg_retaddr)
689 #define	_NGI_FN(i) ((i)->body.fn.fn_fn.fn_fn)
690 #define	_NGI_FN2(i) ((i)->body.fn.fn_fn.fn_fn2)
691 #define	_NGI_ARG1(i) ((i)->body.fn.fn_arg1)
692 #define	_NGI_ARG2(i) ((i)->body.fn.fn_arg2)
693 #define	_NGI_NODE(i) ((i)->el_dest)
694 #define	_NGI_HOOK(i) ((i)->el_hook)
695 #define	_NGI_SET_HOOK(i,h) do { _NGI_HOOK(i) = h; h = NULL;} while (0)
696 #define	_NGI_CLR_HOOK(i)   do {						\
697 		hook_p _hook = _NGI_HOOK(i);				\
698 		if (_hook) {						\
699 			_NG_HOOK_UNREF(_hook);				\
700 			_NGI_HOOK(i) = NULL;				\
701 		}							\
702 	} while (0)
703 #define	_NGI_SET_NODE(i,n) do { _NGI_NODE(i) = n; n = NULL;} while (0)
704 #define	_NGI_CLR_NODE(i)   do {						\
705 		node_p _node = _NGI_NODE(i);				\
706 		if (_node) {						\
707 			_NG_NODE_UNREF(_node);				\
708 			_NGI_NODE(i) = NULL;				\
709 		}							\
710 	} while (0)
711 
712 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/
713 void				dumpitem(item_p item, char *file, int line);
714 static __inline void		_ngi_check(item_p item, char *file, int line) ;
715 static __inline struct mbuf **	_ngi_m(item_p item, char *file, int line) ;
716 static __inline ng_ID_t *	_ngi_retaddr(item_p item, char *file, int line);
717 static __inline struct ng_mesg ** _ngi_msg(item_p item, char *file, int line) ;
718 static __inline ng_item_fn **	_ngi_fn(item_p item, char *file, int line) ;
719 static __inline ng_item_fn2 **	_ngi_fn2(item_p item, char *file, int line) ;
720 static __inline void **		_ngi_arg1(item_p item, char *file, int line) ;
721 static __inline int *		_ngi_arg2(item_p item, char *file, int line) ;
722 static __inline node_p		_ngi_node(item_p item, char *file, int line);
723 static __inline hook_p		_ngi_hook(item_p item, char *file, int line);
724 
725 static __inline void
726 _ngi_check(item_p item, char *file, int line)
727 {
728 	(item)->lastline = line;
729 	(item)->lastfile = file;
730 }
731 
732 static __inline struct mbuf **
733 _ngi_m(item_p item, char *file, int line)
734 {
735 	_ngi_check(item, file, line);
736 	return (&_NGI_M(item));
737 }
738 
739 static __inline struct ng_mesg **
740 _ngi_msg(item_p item, char *file, int line)
741 {
742 	_ngi_check(item, file, line);
743 	return (&_NGI_MSG(item));
744 }
745 
746 static __inline ng_ID_t *
747 _ngi_retaddr(item_p item, char *file, int line)
748 {
749 	_ngi_check(item, file, line);
750 	return (&_NGI_RETADDR(item));
751 }
752 
753 static __inline ng_item_fn **
754 _ngi_fn(item_p item, char *file, int line)
755 {
756 	_ngi_check(item, file, line);
757 	return (&_NGI_FN(item));
758 }
759 
760 static __inline ng_item_fn2 **
761 _ngi_fn2(item_p item, char *file, int line)
762 {
763 	_ngi_check(item, file, line);
764 	return (&_NGI_FN2(item));
765 }
766 
767 static __inline void **
768 _ngi_arg1(item_p item, char *file, int line)
769 {
770 	_ngi_check(item, file, line);
771 	return (&_NGI_ARG1(item));
772 }
773 
774 static __inline int *
775 _ngi_arg2(item_p item, char *file, int line)
776 {
777 	_ngi_check(item, file, line);
778 	return (&_NGI_ARG2(item));
779 }
780 
781 static __inline node_p
782 _ngi_node(item_p item, char *file, int line)
783 {
784 	_ngi_check(item, file, line);
785 	return (_NGI_NODE(item));
786 }
787 
788 static __inline hook_p
789 _ngi_hook(item_p item, char *file, int line)
790 {
791 	_ngi_check(item, file, line);
792 	return (_NGI_HOOK(item));
793 }
794 
795 #define NGI_M(i)	(*_ngi_m(i, _NN_))
796 #define NGI_MSG(i)	(*_ngi_msg(i, _NN_))
797 #define NGI_RETADDR(i)	(*_ngi_retaddr(i, _NN_))
798 #define NGI_FN(i)	(*_ngi_fn(i, _NN_))
799 #define NGI_FN2(i)	(*_ngi_fn2(i, _NN_))
800 #define NGI_ARG1(i)	(*_ngi_arg1(i, _NN_))
801 #define NGI_ARG2(i)	(*_ngi_arg2(i, _NN_))
802 #define NGI_HOOK(i)	_ngi_hook(i, _NN_)
803 #define NGI_NODE(i)	_ngi_node(i, _NN_)
804 #define	NGI_SET_HOOK(i,h)						\
805 	do { _ngi_check(i, _NN_); _NGI_SET_HOOK(i, h); } while (0)
806 #define	NGI_CLR_HOOK(i)							\
807 	do { _ngi_check(i, _NN_); _NGI_CLR_HOOK(i); } while (0)
808 #define	NGI_SET_NODE(i,n)						\
809 	do { _ngi_check(i, _NN_); _NGI_SET_NODE(i, n); } while (0)
810 #define	NGI_CLR_NODE(i)							\
811 	do { _ngi_check(i, _NN_); _NGI_CLR_NODE(i); } while (0)
812 
813 #define NG_FREE_ITEM(item)						\
814 	do {								\
815 		_ngi_check(item, _NN_);					\
816 		ng_free_item((item));					\
817 	} while (0)
818 
819 #define	SAVE_LINE(item)							\
820 	do {								\
821 		(item)->lastline = __LINE__;				\
822 		(item)->lastfile = __FILE__;				\
823 	} while (0)
824 
825 #else	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
826 
827 #define NGI_M(i)	_NGI_M(i)
828 #define NGI_MSG(i)	_NGI_MSG(i)
829 #define NGI_RETADDR(i)	_NGI_RETADDR(i)
830 #define NGI_FN(i)	_NGI_FN(i)
831 #define NGI_FN2(i)	_NGI_FN2(i)
832 #define NGI_ARG1(i)	_NGI_ARG1(i)
833 #define NGI_ARG2(i)	_NGI_ARG2(i)
834 #define	NGI_NODE(i)	_NGI_NODE(i)
835 #define	NGI_HOOK(i)	_NGI_HOOK(i)
836 #define	NGI_SET_HOOK(i,h) _NGI_SET_HOOK(i,h)
837 #define	NGI_CLR_HOOK(i)	  _NGI_CLR_HOOK(i)
838 #define	NGI_SET_NODE(i,n) _NGI_SET_NODE(i,n)
839 #define	NGI_CLR_NODE(i)	  _NGI_CLR_NODE(i)
840 
841 #define	NG_FREE_ITEM(item)	ng_free_item((item))
842 #define	SAVE_LINE(item)		do {} while (0)
843 
844 #endif	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
845 
846 #define NGI_GET_M(i,m)							\
847 	do {								\
848 		(m) = NGI_M(i);						\
849 		_NGI_M(i) = NULL;					\
850 	} while (0)
851 
852 #define NGI_GET_MSG(i,m)						\
853 	do {								\
854 		(m) = NGI_MSG(i);					\
855 		_NGI_MSG(i) = NULL;					\
856 	} while (0)
857 
858 #define NGI_GET_NODE(i,n)	/* YOU NOW HAVE THE REFERENCE */	\
859 	do {								\
860 		(n) = NGI_NODE(i);					\
861 		_NGI_NODE(i) = NULL;					\
862 	} while (0)
863 
864 #define NGI_GET_HOOK(i,h)						\
865 	do {								\
866 		(h) = NGI_HOOK(i);					\
867 		_NGI_HOOK(i) = NULL;					\
868 	} while (0)
869 
870 #define NGI_SET_WRITER(i)	((i)->el_flags &= ~NGQF_QMODE)
871 #define NGI_SET_READER(i)	((i)->el_flags |= NGQF_QREADER)
872 
873 #define NGI_QUEUED_READER(i)	((i)->el_flags & NGQF_QREADER)
874 #define NGI_QUEUED_WRITER(i)	(((i)->el_flags & NGQF_QMODE) == NGQF_QWRITER)
875 
876 /**********************************************************************
877 * Data macros.  Send, manipulate and free.
878 **********************************************************************/
879 /*
880  * Assuming the data is already ok, just set the new address and send
881  */
882 #define NG_FWD_ITEM_HOOK_FLAGS(error, item, hook, flags)		\
883 	do {								\
884 		(error) =						\
885 		    ng_address_hook(NULL, (item), (hook), NG_NOFLAGS);	\
886 		if (error == 0) {					\
887 			SAVE_LINE(item);				\
888 			(error) = ng_snd_item((item), (flags));		\
889 		}							\
890 		(item) = NULL;						\
891 	} while (0)
892 #define	NG_FWD_ITEM_HOOK(error, item, hook)	\
893 		NG_FWD_ITEM_HOOK_FLAGS(error, item, hook, NG_NOFLAGS)
894 
895 /*
896  * Forward a data packet. Mbuf pointer is updated to new value. We
897  * presume you dealt with the old one when you update it to the new one
898  * (or it maybe the old one). We got a packet and possibly had to modify
899  * the mbuf. You should probably use NGI_GET_M() if you are going to use
900  * this too.
901  */
902 #define NG_FWD_NEW_DATA_FLAGS(error, item, hook, m, flags)		\
903 	do {								\
904 		NGI_M(item) = (m);					\
905 		(m) = NULL;						\
906 		NG_FWD_ITEM_HOOK_FLAGS(error, item, hook, flags);	\
907 	} while (0)
908 #define	NG_FWD_NEW_DATA(error, item, hook, m)	\
909 		NG_FWD_NEW_DATA_FLAGS(error, item, hook, m, NG_NOFLAGS)
910 
911 /* Send a previously unpackaged mbuf. XXX: This should be called
912  * NG_SEND_DATA in future, but this name is kept for compatibility
913  * reasons.
914  */
915 #define NG_SEND_DATA_FLAGS(error, hook, m, flags)			\
916 	do {								\
917 		item_p _item;						\
918 		if ((_item = ng_package_data((m), flags))) {		\
919 			NG_FWD_ITEM_HOOK_FLAGS(error, _item, hook, flags);\
920 		} else {						\
921 			(error) = ENOMEM;				\
922 		}							\
923 		(m) = NULL;						\
924 	} while (0)
925 
926 #define NG_SEND_DATA_ONLY(error, hook, m)	\
927 		NG_SEND_DATA_FLAGS(error, hook, m, NG_NOFLAGS)
928 /* NG_SEND_DATA() compat for meta-data times */
929 #define	NG_SEND_DATA(error, hook, m, x)	\
930 		NG_SEND_DATA_FLAGS(error, hook, m, NG_NOFLAGS)
931 
932 #define NG_FREE_MSG(msg)						\
933 	do {								\
934 		if ((msg)) {						\
935 			free((msg), M_NETGRAPH_MSG);			\
936 			(msg) = NULL;					\
937 		}	 						\
938 	} while (0)
939 
940 #define NG_FREE_M(m)							\
941 	do {								\
942 		if ((m)) {						\
943 			m_freem((m));					\
944 			(m) = NULL;					\
945 		}							\
946 	} while (0)
947 
948 /*****************************************
949 * Message macros
950 *****************************************/
951 
952 #define NG_SEND_MSG_HOOK(error, here, msg, hook, retaddr)		\
953 	do {								\
954 		item_p _item;						\
955 		if ((_item = ng_package_msg(msg, NG_NOFLAGS)) == NULL) {\
956 			(msg) = NULL;					\
957 			(error) = ENOMEM;				\
958 			break;						\
959 		}							\
960 		if (((error) = ng_address_hook((here), (_item),		\
961 					(hook), (retaddr))) == 0) {	\
962 			SAVE_LINE(_item);				\
963 			(error) = ng_snd_item((_item), 0);		\
964 		}							\
965 		(msg) = NULL;						\
966 	} while (0)
967 
968 #define NG_SEND_MSG_PATH(error, here, msg, path, retaddr)		\
969 	do {								\
970 		item_p _item;						\
971 		if ((_item = ng_package_msg(msg, NG_NOFLAGS)) == NULL) {\
972 			(msg) = NULL;					\
973 			(error) = ENOMEM;				\
974 			break;						\
975 		}							\
976 		if (((error) = ng_address_path((here), (_item),		\
977 					(path), (retaddr))) == 0) {	\
978 			SAVE_LINE(_item);				\
979 			(error) = ng_snd_item((_item), 0);		\
980 		}							\
981 		(msg) = NULL;						\
982 	} while (0)
983 
984 #define NG_SEND_MSG_ID(error, here, msg, ID, retaddr)			\
985 	do {								\
986 		item_p _item;						\
987 		if ((_item = ng_package_msg(msg, NG_NOFLAGS)) == NULL) {\
988 			(msg) = NULL;					\
989 			(error) = ENOMEM;				\
990 			break;						\
991 		}							\
992 		if (((error) = ng_address_ID((here), (_item),		\
993 					(ID), (retaddr))) == 0) {	\
994 			SAVE_LINE(_item);				\
995 			(error) = ng_snd_item((_item), 0);		\
996 		}							\
997 		(msg) = NULL;						\
998 	} while (0)
999 
1000 /*
1001  * Redirect the message to the next hop using the given hook.
1002  * ng_retarget_msg() frees the item if there is an error
1003  * and returns an error code.  It returns 0 on success.
1004  */
1005 #define NG_FWD_MSG_HOOK(error, here, item, hook, retaddr)		\
1006 	do {								\
1007 		if (((error) = ng_address_hook((here), (item),		\
1008 					(hook), (retaddr))) == 0) {	\
1009 			SAVE_LINE(item);				\
1010 			(error) = ng_snd_item((item), 0);		\
1011 		}							\
1012 		(item) = NULL;						\
1013 	} while (0)
1014 
1015 /*
1016  * Send a queue item back to it's originator with a response message.
1017  * Assume original message was removed and freed separatly.
1018  */
1019 #define NG_RESPOND_MSG(error, here, item, resp)				\
1020 	do {								\
1021 		if (resp) {						\
1022 			ng_ID_t _dest = NGI_RETADDR(item);		\
1023 			NGI_RETADDR(item) = 0;				\
1024 			NGI_MSG(item) = resp;				\
1025 			if ((error = ng_address_ID((here), (item),	\
1026 					_dest, 0)) == 0) {		\
1027 				SAVE_LINE(item);			\
1028 				(error) = ng_snd_item((item), NG_QUEUE);\
1029 			}						\
1030 		} else							\
1031 			NG_FREE_ITEM(item);				\
1032 		(item) = NULL;						\
1033 	} while (0)
1034 
1035 
1036 /***********************************************************************
1037  ******** Structures Definitions and Macros for defining a node  *******
1038  ***********************************************************************
1039  *
1040  * Here we define the structures needed to actually define a new node
1041  * type.
1042  */
1043 
1044 /*
1045  * Command list -- each node type specifies the command that it knows
1046  * how to convert between ASCII and binary using an array of these.
1047  * The last element in the array must be a terminator with cookie=0.
1048  */
1049 
1050 struct ng_cmdlist {
1051 	u_int32_t			cookie;		/* command typecookie */
1052 	int				cmd;		/* command number */
1053 	const char			*name;		/* command name */
1054 	const struct ng_parse_type	*mesgType;	/* args if !NGF_RESP */
1055 	const struct ng_parse_type	*respType;	/* args if NGF_RESP */
1056 };
1057 
1058 /*
1059  * Structure of a node type
1060  * If data is sent to the "rcvdata()" entrypoint then the system
1061  * may decide to defer it until later by queing it with the normal netgraph
1062  * input queuing system.  This is decidde by the HK_QUEUE flag being set in
1063  * the flags word of the peer (receiving) hook. The dequeuing mechanism will
1064  * ensure it is not requeued again.
1065  * Note the input queueing system is to allow modules
1066  * to 'release the stack' or to pass data across spl layers.
1067  * The data will be redelivered as soon as the NETISR code runs
1068  * which may be almost immediatly.  A node may also do it's own queueing
1069  * for other reasons (e.g. device output queuing).
1070  */
1071 struct ng_type {
1072 
1073 	u_int32_t	version; 	/* must equal NG_API_VERSION */
1074 	const char	*name;		/* Unique type name */
1075 	modeventhand_t	mod_event;	/* Module event handler (optional) */
1076 	ng_constructor_t *constructor;	/* Node constructor */
1077 	ng_rcvmsg_t	*rcvmsg;	/* control messages come here */
1078 	ng_close_t	*close;		/* warn about forthcoming shutdown */
1079 	ng_shutdown_t	*shutdown;	/* reset, and free resources */
1080 	ng_newhook_t	*newhook;	/* first notification of new hook */
1081 	ng_findhook_t	*findhook;	/* only if you have lots of hooks */
1082 	ng_connect_t	*connect;	/* final notification of new hook */
1083 	ng_rcvdata_t	*rcvdata;	/* data comes here */
1084 	ng_disconnect_t	*disconnect;	/* notify on disconnect */
1085 
1086 	const struct	ng_cmdlist *cmdlist;	/* commands we can convert */
1087 
1088 	/* R/W data private to the base netgraph code DON'T TOUCH! */
1089 	LIST_ENTRY(ng_type) types;		/* linked list of all types */
1090 	int		    refs;		/* number of instances */
1091 };
1092 
1093 /*
1094  * Use the NETGRAPH_INIT() macro to link a node type into the
1095  * netgraph system. This works for types compiled into the kernel
1096  * as well as KLD modules. The first argument should be the type
1097  * name (eg, echo) and the second a pointer to the type struct.
1098  *
1099  * If a different link time is desired, e.g., a device driver that
1100  * needs to install its netgraph type before probing, use the
1101  * NETGRAPH_INIT_ORDERED() macro instead.  Device drivers probably
1102  * want to use SI_SUB_DRIVERS/SI_ORDER_FIRST.
1103  */
1104 
1105 #define NETGRAPH_INIT_ORDERED(typename, typestructp, sub, order)	\
1106 static moduledata_t ng_##typename##_mod = {				\
1107 	"ng_" #typename,						\
1108 	ng_mod_event,							\
1109 	(typestructp)							\
1110 };									\
1111 DECLARE_MODULE(ng_##typename, ng_##typename##_mod, sub, order);		\
1112 MODULE_DEPEND(ng_##typename, netgraph,	NG_ABI_VERSION,			\
1113 					NG_ABI_VERSION,			\
1114 					NG_ABI_VERSION)
1115 
1116 #define NETGRAPH_INIT(tn, tp)						\
1117 	NETGRAPH_INIT_ORDERED(tn, tp, SI_SUB_PSEUDO, SI_ORDER_MIDDLE)
1118 
1119 /* Special malloc() type for netgraph structs and ctrl messages */
1120 /* Only these two types should be visible to nodes */
1121 MALLOC_DECLARE(M_NETGRAPH);
1122 MALLOC_DECLARE(M_NETGRAPH_MSG);
1123 
1124 /* declare the base of the netgraph sysclt hierarchy */
1125 /* but only if this file cares about sysctls */
1126 #ifdef	SYSCTL_DECL
1127 SYSCTL_DECL(_net_graph);
1128 #endif
1129 
1130 /*
1131  * Methods that the nodes can use.
1132  * Many of these methods should usually NOT be used directly but via
1133  * Macros above.
1134  */
1135 int	ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr);
1136 int	ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr);
1137 int	ng_address_path(node_p here, item_p item, char *address, ng_ID_t raddr);
1138 int	ng_bypass(hook_p hook1, hook_p hook2);
1139 hook_p	ng_findhook(node_p node, const char *name);
1140 struct	ng_type *ng_findtype(const char *type);
1141 int	ng_make_node_common(struct ng_type *typep, node_p *nodep);
1142 int	ng_name_node(node_p node, const char *name);
1143 node_p	ng_name2noderef(node_p node, const char *name);
1144 int	ng_newtype(struct ng_type *tp);
1145 ng_ID_t ng_node2ID(node_p node);
1146 item_p	ng_package_data(struct mbuf *m, int flags);
1147 item_p	ng_package_msg(struct ng_mesg *msg, int flags);
1148 item_p	ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg);
1149 void	ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr);
1150 int	ng_rmhook_self(hook_p hook);	/* if a node wants to kill a hook */
1151 int	ng_rmnode_self(node_p here);	/* if a node wants to suicide */
1152 int	ng_rmtype(struct ng_type *tp);
1153 int	ng_snd_item(item_p item, int queue);
1154 int 	ng_send_fn(node_p node, hook_p hook, ng_item_fn *fn, void *arg1,
1155 	int arg2);
1156 int 	ng_send_fn1(node_p node, hook_p hook, ng_item_fn *fn, void *arg1,
1157 	int arg2, int flags);
1158 int 	ng_send_fn2(node_p node, hook_p hook, item_p pitem, ng_item_fn2 *fn,
1159 	void *arg1, int arg2, int flags);
1160 int	ng_uncallout(struct callout *c, node_p node);
1161 int	ng_callout(struct callout *c, node_p node, hook_p hook, int ticks,
1162 	    ng_item_fn *fn, void * arg1, int arg2);
1163 #define	ng_callout_init(c)	callout_init(c, CALLOUT_MPSAFE)
1164 
1165 /* Flags for netgraph functions. */
1166 #define	NG_NOFLAGS	0x00000000	/* no special options */
1167 #define	NG_QUEUE	0x00000001	/* enqueue item, don't dispatch */
1168 #define	NG_WAITOK	0x00000002	/* use M_WAITOK, etc. */
1169 /* XXXGL: NG_PROGRESS unused since ng_base.c rev. 1.136. Should be deleted? */
1170 #define	NG_PROGRESS	0x00000004	/* return EINPROGRESS if queued */
1171 #define	NG_REUSE_ITEM	0x00000008	/* supplied item should be reused */
1172 
1173 /*
1174  * prototypes the user should DEFINITELY not use directly
1175  */
1176 void	ng_free_item(item_p item); /* Use NG_FREE_ITEM instead */
1177 int	ng_mod_event(module_t mod, int what, void *arg);
1178 
1179 /*
1180  * Tag definitions and constants
1181  */
1182 
1183 #define	NG_TAG_PRIO	1
1184 
1185 struct ng_tag_prio {
1186 	struct m_tag	tag;
1187 	char	priority;
1188 	char	discardability;
1189 };
1190 
1191 #define	NG_PRIO_CUTOFF		32
1192 #define	NG_PRIO_LINKSTATE	64
1193 
1194 /* Macros and declarations to keep compatibility with metadata, which
1195  * is obsoleted now. To be deleted.
1196  */
1197 typedef void *meta_p;
1198 #define _NGI_META(i)	NULL
1199 #define NGI_META(i)	NULL
1200 #define NG_FREE_META(meta)
1201 #define NGI_GET_META(i,m)
1202 #define	ng_copy_meta(meta) NULL
1203 
1204 /* Hash related definitions */
1205 #define	NG_ID_HASH_SIZE 128 /* most systems wont need even this many */
1206 #define	NG_NAME_HASH_SIZE 128 /* most systems wont need even this many */
1207 
1208 /*
1209  * Mark the current thread when called from the outbound path of the
1210  * network stack, in order to enforce queuing on ng nodes calling into
1211  * the inbound network stack path.
1212  */
1213 #define NG_OUTBOUND_THREAD_REF()					\
1214 	curthread->td_ng_outbound++
1215 #define NG_OUTBOUND_THREAD_UNREF()					\
1216 	do {								\
1217 		curthread->td_ng_outbound--;				\
1218 		KASSERT(curthread->td_ng_outbound >= 0,			\
1219 		    ("%s: negative td_ng_outbound", __func__));		\
1220 	} while (0)
1221 
1222 #endif /* _NETGRAPH_NETGRAPH_H_ */
1223