xref: /freebsd/sys/netgraph/netgraph.h (revision dd41de95a84d979615a2ef11df6850622bf6184e)
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  * 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 typedef	struct ng_item const *item_cp;
91 typedef struct ng_hook const *hook_cp;
92 #ifdef	NETGRAPH_DEBUG
93 typedef struct ng_node       *node_cp; /* annotated during debug */
94 #else	/* NETGRAPH_DEBUG */
95 typedef struct ng_node const *node_cp;
96 #endif	/* NETGRAPH_DEBUG */
97 
98 /* node method definitions */
99 typedef	int	ng_constructor_t(node_p node);
100 typedef	int	ng_close_t(node_p node);
101 typedef	int	ng_shutdown_t(node_p node);
102 typedef	int	ng_newhook_t(node_p node, hook_p hook, const char *name);
103 typedef	hook_p	ng_findhook_t(node_p node, const char *name);
104 typedef	int	ng_connect_t(hook_p hook);
105 typedef	int	ng_rcvmsg_t(node_p node, item_p item, hook_p lasthook);
106 typedef	int	ng_rcvdata_t(hook_p hook, item_p item);
107 typedef	int	ng_disconnect_t(hook_p hook);
108 typedef	int	ng_rcvitem (node_p node, hook_p hook, item_p item);
109 
110 /***********************************************************************
111  ***************** Hook Structure and Methods **************************
112  ***********************************************************************
113  *
114  * Structure of a hook
115  */
116 struct ng_hook {
117 	char	hk_name[NG_HOOKSIZ];	/* what this node knows this link as */
118 	void   *hk_private;		/* node dependent ID for this hook */
119 	int	hk_flags;		/* info about this hook/link */
120 	int	hk_type;		/* tbd: hook data link type */
121 	struct	ng_hook *hk_peer;	/* the other end of this link */
122 	struct	ng_node *hk_node;	/* The node this hook is attached to */
123 	LIST_ENTRY(ng_hook) hk_hooks;	/* linked list of all hooks on node */
124 	ng_rcvmsg_t	*hk_rcvmsg;	/* control messages come here */
125 	ng_rcvdata_t	*hk_rcvdata;	/* data comes here */
126 	int	hk_refs;		/* dont actually free this till 0 */
127 #ifdef	NETGRAPH_DEBUG /*----------------------------------------------*/
128 #define HK_MAGIC 0x78573011
129 	int	hk_magic;
130 	char	*lastfile;
131 	int	lastline;
132 	SLIST_ENTRY(ng_hook)	  hk_all;		/* all existing items */
133 #endif	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
134 };
135 /* Flags for a hook */
136 #define HK_INVALID		0x0001	/* don't trust it! */
137 #define HK_QUEUE		0x0002	/* queue for later delivery */
138 #define HK_FORCE_WRITER		0x0004	/* Incoming data queued as a writer */
139 #define HK_DEAD			0x0008	/* This is the dead hook.. don't free */
140 #define HK_HI_STACK		0x0010	/* Hook has hi stack usage */
141 #define HK_TO_INBOUND		0x0020	/* Hook on ntw. stack inbound path. */
142 
143 /*
144  * Public Methods for hook
145  * If you can't do it with these you probably shouldn;t be doing it.
146  */
147 void ng_unref_hook(hook_p hook); /* don't move this */
148 #define	_NG_HOOK_REF(hook)	refcount_acquire(&(hook)->hk_refs)
149 #define _NG_HOOK_NAME(hook)	((hook)->hk_name)
150 #define _NG_HOOK_UNREF(hook)	ng_unref_hook(hook)
151 #define	_NG_HOOK_SET_PRIVATE(hook, val)	do {(hook)->hk_private = val;} while (0)
152 #define	_NG_HOOK_SET_RCVMSG(hook, val)	do {(hook)->hk_rcvmsg = val;} while (0)
153 #define	_NG_HOOK_SET_RCVDATA(hook, val)	do {(hook)->hk_rcvdata = val;} while (0)
154 #define	_NG_HOOK_PRIVATE(hook)	((hook)->hk_private)
155 #define _NG_HOOK_NOT_VALID(hook)	((hook)->hk_flags & HK_INVALID)
156 #define _NG_HOOK_IS_VALID(hook)	(!((hook)->hk_flags & HK_INVALID))
157 #define _NG_HOOK_NODE(hook)	((hook)->hk_node) /* only rvalue! */
158 #define _NG_HOOK_PEER(hook)	((hook)->hk_peer) /* only rvalue! */
159 #define _NG_HOOK_FORCE_WRITER(hook)				\
160 		do { hook->hk_flags |= HK_FORCE_WRITER; } while (0)
161 #define _NG_HOOK_FORCE_QUEUE(hook) do { hook->hk_flags |= HK_QUEUE; } while (0)
162 #define _NG_HOOK_SET_TO_INBOUND(hook)				\
163 		do { hook->hk_flags |= HK_TO_INBOUND; } while (0)
164 #define _NG_HOOK_HI_STACK(hook) do { hook->hk_flags |= HK_HI_STACK; } while (0)
165 
166 /* Some shortcuts */
167 #define NG_PEER_NODE(hook)	NG_HOOK_NODE(NG_HOOK_PEER(hook))
168 #define NG_PEER_HOOK_NAME(hook)	NG_HOOK_NAME(NG_HOOK_PEER(hook))
169 #define NG_PEER_NODE_NAME(hook)	NG_NODE_NAME(NG_PEER_NODE(hook))
170 
171 #ifdef	NETGRAPH_DEBUG /*----------------------------------------------*/
172 #define _NN_ __FILE__,__LINE__
173 void	dumphook (hook_p hook, char *file, int line);
174 static __inline void	_chkhook(hook_p hook, char *file, int line);
175 static __inline void	_ng_hook_ref(hook_p hook, char * file, int line);
176 static __inline char *	_ng_hook_name(hook_p hook, char * file, int line);
177 static __inline void	_ng_hook_unref(hook_p hook, char * file, int line);
178 static __inline void	_ng_hook_set_private(hook_p hook,
179 				void * val, char * file, int line);
180 static __inline void	_ng_hook_set_rcvmsg(hook_p hook,
181 				ng_rcvmsg_t *val, char * file, int line);
182 static __inline void	_ng_hook_set_rcvdata(hook_p hook,
183 				ng_rcvdata_t *val, char * file, int line);
184 static __inline void *	_ng_hook_private(hook_p hook, char * file, int line);
185 static __inline int	_ng_hook_not_valid(hook_p hook, char * file, int line);
186 static __inline int	_ng_hook_is_valid(hook_p hook, char * file, int line);
187 static __inline node_p	_ng_hook_node(hook_p hook, char * file, int line);
188 static __inline hook_p	_ng_hook_peer(hook_p hook, char * file, int line);
189 static __inline void	_ng_hook_force_writer(hook_p hook, char * file,
190 				int line);
191 static __inline void	_ng_hook_force_queue(hook_p hook, char * file,
192 				int line);
193 static __inline void	_ng_hook_set_to_inbound(hook_p hook, char * file,
194 				int line);
195 
196 static __inline void
197 _chkhook(hook_p hook, char *file, int line)
198 {
199 	if (hook->hk_magic != HK_MAGIC) {
200 		printf("Accessing freed ");
201 		dumphook(hook, file, line);
202 	}
203 	hook->lastline = line;
204 	hook->lastfile = file;
205 }
206 
207 static __inline void
208 _ng_hook_ref(hook_p hook, char * file, int line)
209 {
210 	_chkhook(hook, file, line);
211 	_NG_HOOK_REF(hook);
212 }
213 
214 static __inline char *
215 _ng_hook_name(hook_p hook, char * file, int line)
216 {
217 	_chkhook(hook, file, line);
218 	return (_NG_HOOK_NAME(hook));
219 }
220 
221 static __inline void
222 _ng_hook_unref(hook_p hook, char * file, int line)
223 {
224 	_chkhook(hook, file, line);
225 	_NG_HOOK_UNREF(hook);
226 }
227 
228 static __inline void
229 _ng_hook_set_private(hook_p hook, void *val, char * file, int line)
230 {
231 	_chkhook(hook, file, line);
232 	_NG_HOOK_SET_PRIVATE(hook, val);
233 }
234 
235 static __inline void
236 _ng_hook_set_rcvmsg(hook_p hook, ng_rcvmsg_t *val, char * file, int line)
237 {
238 	_chkhook(hook, file, line);
239 	_NG_HOOK_SET_RCVMSG(hook, val);
240 }
241 
242 static __inline void
243 _ng_hook_set_rcvdata(hook_p hook, ng_rcvdata_t *val, char * file, int line)
244 {
245 	_chkhook(hook, file, line);
246 	_NG_HOOK_SET_RCVDATA(hook, val);
247 }
248 
249 static __inline void *
250 _ng_hook_private(hook_p hook, char * file, int line)
251 {
252 	_chkhook(hook, file, line);
253 	return (_NG_HOOK_PRIVATE(hook));
254 }
255 
256 static __inline int
257 _ng_hook_not_valid(hook_p hook, char * file, int line)
258 {
259 	_chkhook(hook, file, line);
260 	return (_NG_HOOK_NOT_VALID(hook));
261 }
262 
263 static __inline int
264 _ng_hook_is_valid(hook_p hook, char * file, int line)
265 {
266 	_chkhook(hook, file, line);
267 	return (_NG_HOOK_IS_VALID(hook));
268 }
269 
270 static __inline node_p
271 _ng_hook_node(hook_p hook, char * file, int line)
272 {
273 	_chkhook(hook, file, line);
274 	return (_NG_HOOK_NODE(hook));
275 }
276 
277 static __inline hook_p
278 _ng_hook_peer(hook_p hook, char * file, int line)
279 {
280 	_chkhook(hook, file, line);
281 	return (_NG_HOOK_PEER(hook));
282 }
283 
284 static __inline void
285 _ng_hook_force_writer(hook_p hook, char * file, int line)
286 {
287 	_chkhook(hook, file, line);
288 	_NG_HOOK_FORCE_WRITER(hook);
289 }
290 
291 static __inline void
292 _ng_hook_force_queue(hook_p hook, char * file, int line)
293 {
294 	_chkhook(hook, file, line);
295 	_NG_HOOK_FORCE_QUEUE(hook);
296 }
297 
298 static __inline void
299 _ng_hook_set_to_inbound(hook_p hook, char * file, int line)
300 {
301 	_chkhook(hook, file, line);
302 	_NG_HOOK_SET_TO_INBOUND(hook);
303 }
304 
305 static __inline void
306 _ng_hook_hi_stack(hook_p hook, char * file, int line)
307 {
308 	_chkhook(hook, file, line);
309 	_NG_HOOK_HI_STACK(hook);
310 }
311 
312 #define	NG_HOOK_REF(hook)		_ng_hook_ref(hook, _NN_)
313 #define NG_HOOK_NAME(hook)		_ng_hook_name(hook, _NN_)
314 #define NG_HOOK_UNREF(hook)		_ng_hook_unref(hook, _NN_)
315 #define	NG_HOOK_SET_PRIVATE(hook, val)	_ng_hook_set_private(hook, val, _NN_)
316 #define	NG_HOOK_SET_RCVMSG(hook, val)	_ng_hook_set_rcvmsg(hook, val, _NN_)
317 #define	NG_HOOK_SET_RCVDATA(hook, val)	_ng_hook_set_rcvdata(hook, val, _NN_)
318 #define	NG_HOOK_PRIVATE(hook)		_ng_hook_private(hook, _NN_)
319 #define NG_HOOK_NOT_VALID(hook)		_ng_hook_not_valid(hook, _NN_)
320 #define NG_HOOK_IS_VALID(hook)		_ng_hook_is_valid(hook, _NN_)
321 #define NG_HOOK_NODE(hook)		_ng_hook_node(hook, _NN_)
322 #define NG_HOOK_PEER(hook)		_ng_hook_peer(hook, _NN_)
323 #define NG_HOOK_FORCE_WRITER(hook)	_ng_hook_force_writer(hook, _NN_)
324 #define NG_HOOK_FORCE_QUEUE(hook)	_ng_hook_force_queue(hook, _NN_)
325 #define NG_HOOK_SET_TO_INBOUND(hook)	_ng_hook_set_to_inbound(hook, _NN_)
326 #define NG_HOOK_HI_STACK(hook)		_ng_hook_hi_stack(hook, _NN_)
327 
328 #else	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
329 
330 #define	NG_HOOK_REF(hook)		_NG_HOOK_REF(hook)
331 #define NG_HOOK_NAME(hook)		_NG_HOOK_NAME(hook)
332 #define NG_HOOK_UNREF(hook)		_NG_HOOK_UNREF(hook)
333 #define	NG_HOOK_SET_PRIVATE(hook, val)	_NG_HOOK_SET_PRIVATE(hook, val)
334 #define	NG_HOOK_SET_RCVMSG(hook, val)	_NG_HOOK_SET_RCVMSG(hook, val)
335 #define	NG_HOOK_SET_RCVDATA(hook, val)	_NG_HOOK_SET_RCVDATA(hook, val)
336 #define	NG_HOOK_PRIVATE(hook)		_NG_HOOK_PRIVATE(hook)
337 #define NG_HOOK_NOT_VALID(hook)		_NG_HOOK_NOT_VALID(hook)
338 #define NG_HOOK_IS_VALID(hook)		_NG_HOOK_IS_VALID(hook)
339 #define NG_HOOK_NODE(hook)		_NG_HOOK_NODE(hook)
340 #define NG_HOOK_PEER(hook)		_NG_HOOK_PEER(hook)
341 #define NG_HOOK_FORCE_WRITER(hook)	_NG_HOOK_FORCE_WRITER(hook)
342 #define NG_HOOK_FORCE_QUEUE(hook)	_NG_HOOK_FORCE_QUEUE(hook)
343 #define NG_HOOK_SET_TO_INBOUND(hook)	_NG_HOOK_SET_TO_INBOUND(hook)
344 #define NG_HOOK_HI_STACK(hook)		_NG_HOOK_HI_STACK(hook)
345 
346 #endif	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
347 
348 /***********************************************************************
349  ***************** Node Structure and Methods **************************
350  ***********************************************************************
351  * Structure of a node
352  * including the eembedded queue structure.
353  *
354  * The structure for queueing Netgraph request items
355  * embedded in the node structure
356  */
357 struct ng_queue {
358 	u_int		q_flags;	/* Current r/w/q lock flags */
359 	u_int		q_flags2;	/* Other queue flags */
360 	struct mtx	q_mtx;
361 	STAILQ_ENTRY(ng_node)	q_work;	/* nodes with work to do */
362 	STAILQ_HEAD(, ng_item)	queue;	/* actually items queue */
363 };
364 
365 struct ng_node {
366 	char	nd_name[NG_NODESIZ];	/* optional globally unique name */
367 	struct	ng_type *nd_type;	/* the installed 'type' */
368 	int	nd_flags;		/* see below for bit definitions */
369 	int	nd_numhooks;		/* number of hooks */
370 	void   *nd_private;		/* node type dependent node ID */
371 	ng_ID_t	nd_ID;			/* Unique per node */
372 	LIST_HEAD(hooks, ng_hook) nd_hooks;	/* linked list of node hooks */
373 	LIST_ENTRY(ng_node)	  nd_nodes;	/* name hash collision list */
374 	LIST_ENTRY(ng_node)	  nd_idnodes;	/* ID hash collision list */
375 	struct	ng_queue	  nd_input_queue; /* input queue for locking */
376 	int	nd_refs;		/* # of references to this node */
377 	struct	vnet		 *nd_vnet;	/* network stack instance */
378 #ifdef	NETGRAPH_DEBUG /*----------------------------------------------*/
379 #define ND_MAGIC 0x59264837
380 	int	nd_magic;
381 	char	*lastfile;
382 	int	lastline;
383 	SLIST_ENTRY(ng_node)	  nd_all;	/* all existing nodes */
384 #endif	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
385 };
386 
387 /* Flags for a node */
388 #define NGF_INVALID	0x00000001	/* free when refs go to 0 */
389 #define NG_INVALID	NGF_INVALID	/* compat for old code */
390 #define NGF_FORCE_WRITER	0x00000004	/* Never multithread this node */
391 #define NG_FORCE_WRITER	NGF_FORCE_WRITER /* compat for old code */
392 #define NGF_CLOSING	0x00000008	/* ng_rmnode() at work */
393 #define NG_CLOSING	NGF_CLOSING	/* compat for old code */
394 #define NGF_REALLY_DIE	0x00000010	/* "persistent" node is unloading */
395 #define NG_REALLY_DIE	NGF_REALLY_DIE	/* compat for old code */
396 #define NGF_HI_STACK	0x00000020	/* node has hi stack usage */
397 #define NGF_TYPE1	0x10000000	/* reserved for type specific storage */
398 #define NGF_TYPE2	0x20000000	/* reserved for type specific storage */
399 #define NGF_TYPE3	0x40000000	/* reserved for type specific storage */
400 #define NGF_TYPE4	0x80000000	/* reserved for type specific storage */
401 
402 /*
403  * Public methods for nodes.
404  * If you can't do it with these you probably shouldn't be doing it.
405  */
406 void	ng_unref_node(node_p node); /* don't move this */
407 #define _NG_NODE_NAME(node)	((node)->nd_name + 0)
408 #define _NG_NODE_HAS_NAME(node)	((node)->nd_name[0] + 0)
409 #define _NG_NODE_ID(node)	((node)->nd_ID + 0)
410 #define	_NG_NODE_REF(node)	refcount_acquire(&(node)->nd_refs)
411 #define	_NG_NODE_UNREF(node)	ng_unref_node(node)
412 #define	_NG_NODE_SET_PRIVATE(node, val)	do {(node)->nd_private = val;} while (0)
413 #define	_NG_NODE_PRIVATE(node)	((node)->nd_private)
414 #define _NG_NODE_IS_VALID(node)	(!((node)->nd_flags & NGF_INVALID))
415 #define _NG_NODE_NOT_VALID(node)	((node)->nd_flags & NGF_INVALID)
416 #define _NG_NODE_NUMHOOKS(node)	((node)->nd_numhooks + 0) /* rvalue */
417 #define _NG_NODE_FORCE_WRITER(node)					\
418 	do{ node->nd_flags |= NGF_FORCE_WRITER; }while (0)
419 #define _NG_NODE_HI_STACK(node)						\
420 	do{ node->nd_flags |= NGF_HI_STACK; }while (0)
421 #define _NG_NODE_REALLY_DIE(node)					\
422 	do{ node->nd_flags |= (NGF_REALLY_DIE|NGF_INVALID); }while (0)
423 #define _NG_NODE_REVIVE(node) \
424 	do { node->nd_flags &= ~NGF_INVALID; } while (0)
425 /*
426  * The hook iterator.
427  * This macro will call a function of type ng_fn_eachhook for each
428  * hook attached to the node. If the function returns 0, then the
429  * iterator will stop and return a pointer to the hook that returned 0.
430  */
431 typedef	int	ng_fn_eachhook(hook_p hook, void* arg);
432 #define _NG_NODE_FOREACH_HOOK(node, fn, arg, rethook)			\
433 	do {								\
434 		hook_p _hook;						\
435 		(rethook) = NULL;					\
436 		LIST_FOREACH(_hook, &((node)->nd_hooks), hk_hooks) {	\
437 			if ((fn)(_hook, arg) == 0) {			\
438 				(rethook) = _hook;			\
439 				break;					\
440 			}						\
441 		}							\
442 	} while (0)
443 
444 #ifdef	NETGRAPH_DEBUG /*----------------------------------------------*/
445 void	dumpnode(node_p node, char *file, int line);
446 static __inline void _chknode(node_p node, char *file, int line);
447 static __inline char * _ng_node_name(node_p node, char *file, int line);
448 static __inline int _ng_node_has_name(node_p node, char *file, int line);
449 static __inline ng_ID_t _ng_node_id(node_p node, char *file, int line);
450 static __inline void _ng_node_ref(node_p node, char *file, int line);
451 static __inline void _ng_node_unref(node_p node, char *file, int line);
452 static __inline void _ng_node_set_private(node_p node, void * val,
453 							char *file, int line);
454 static __inline void * _ng_node_private(node_p node, char *file, int line);
455 static __inline int _ng_node_is_valid(node_p node, char *file, int line);
456 static __inline int _ng_node_not_valid(node_p node, char *file, int line);
457 static __inline int _ng_node_numhooks(node_p node, char *file, int line);
458 static __inline void _ng_node_force_writer(node_p node, char *file, int line);
459 static __inline hook_p _ng_node_foreach_hook(node_p node,
460 			ng_fn_eachhook *fn, void *arg, char *file, int line);
461 static __inline void _ng_node_revive(node_p node, char *file, int line);
462 
463 static __inline void
464 _chknode(node_p node, char *file, int line)
465 {
466 	if (node->nd_magic != ND_MAGIC) {
467 		printf("Accessing freed ");
468 		dumpnode(node, file, line);
469 	}
470 	node->lastline = line;
471 	node->lastfile = file;
472 }
473 
474 static __inline char *
475 _ng_node_name(node_p node, char *file, int line)
476 {
477 	_chknode(node, file, line);
478 	return(_NG_NODE_NAME(node));
479 }
480 
481 static __inline int
482 _ng_node_has_name(node_p node, char *file, int line)
483 {
484 	_chknode(node, file, line);
485 	return(_NG_NODE_HAS_NAME(node));
486 }
487 
488 static __inline ng_ID_t
489 _ng_node_id(node_p node, char *file, int line)
490 {
491 	_chknode(node, file, line);
492 	return(_NG_NODE_ID(node));
493 }
494 
495 static __inline void
496 _ng_node_ref(node_p node, char *file, int line)
497 {
498 	_chknode(node, file, line);
499 	_NG_NODE_REF(node);
500 }
501 
502 static __inline void
503 _ng_node_unref(node_p node, char *file, int line)
504 {
505 	_chknode(node, file, line);
506 	_NG_NODE_UNREF(node);
507 }
508 
509 static __inline void
510 _ng_node_set_private(node_p node, void * val, char *file, int line)
511 {
512 	_chknode(node, file, line);
513 	_NG_NODE_SET_PRIVATE(node, val);
514 }
515 
516 static __inline void *
517 _ng_node_private(node_p node, char *file, int line)
518 {
519 	_chknode(node, file, line);
520 	return (_NG_NODE_PRIVATE(node));
521 }
522 
523 static __inline int
524 _ng_node_is_valid(node_p node, char *file, int line)
525 {
526 	_chknode(node, file, line);
527 	return(_NG_NODE_IS_VALID(node));
528 }
529 
530 static __inline int
531 _ng_node_not_valid(node_p node, char *file, int line)
532 {
533 	_chknode(node, file, line);
534 	return(_NG_NODE_NOT_VALID(node));
535 }
536 
537 static __inline int
538 _ng_node_numhooks(node_p node, char *file, int line)
539 {
540 	_chknode(node, file, line);
541 	return(_NG_NODE_NUMHOOKS(node));
542 }
543 
544 static __inline void
545 _ng_node_force_writer(node_p node, char *file, int line)
546 {
547 	_chknode(node, file, line);
548 	_NG_NODE_FORCE_WRITER(node);
549 }
550 
551 static __inline void
552 _ng_node_hi_stack(node_p node, char *file, int line)
553 {
554 	_chknode(node, file, line);
555 	_NG_NODE_HI_STACK(node);
556 }
557 
558 static __inline void
559 _ng_node_really_die(node_p node, char *file, int line)
560 {
561 	_chknode(node, file, line);
562 	_NG_NODE_REALLY_DIE(node);
563 }
564 
565 static __inline void
566 _ng_node_revive(node_p node, char *file, int line)
567 {
568 	_chknode(node, file, line);
569 	_NG_NODE_REVIVE(node);
570 }
571 
572 static __inline hook_p
573 _ng_node_foreach_hook(node_p node, ng_fn_eachhook *fn, void *arg,
574 						char *file, int line)
575 {
576 	hook_p hook;
577 	_chknode(node, file, line);
578 	_NG_NODE_FOREACH_HOOK(node, fn, arg, hook);
579 	return (hook);
580 }
581 
582 #define NG_NODE_NAME(node)		_ng_node_name(node, _NN_)
583 #define NG_NODE_HAS_NAME(node)		_ng_node_has_name(node, _NN_)
584 #define NG_NODE_ID(node)		_ng_node_id(node, _NN_)
585 #define NG_NODE_REF(node)		_ng_node_ref(node, _NN_)
586 #define	NG_NODE_UNREF(node)		_ng_node_unref(node, _NN_)
587 #define	NG_NODE_SET_PRIVATE(node, val)	_ng_node_set_private(node, val, _NN_)
588 #define	NG_NODE_PRIVATE(node)		_ng_node_private(node, _NN_)
589 #define NG_NODE_IS_VALID(node)		_ng_node_is_valid(node, _NN_)
590 #define NG_NODE_NOT_VALID(node)		_ng_node_not_valid(node, _NN_)
591 #define NG_NODE_FORCE_WRITER(node) 	_ng_node_force_writer(node, _NN_)
592 #define NG_NODE_HI_STACK(node) 		_ng_node_hi_stack(node, _NN_)
593 #define NG_NODE_REALLY_DIE(node) 	_ng_node_really_die(node, _NN_)
594 #define NG_NODE_NUMHOOKS(node)		_ng_node_numhooks(node, _NN_)
595 #define NG_NODE_REVIVE(node)		_ng_node_revive(node, _NN_)
596 #define NG_NODE_FOREACH_HOOK(node, fn, arg, rethook)			      \
597 	do {								      \
598 		rethook = _ng_node_foreach_hook(node, fn, (void *)arg, _NN_); \
599 	} while (0)
600 
601 #else	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
602 
603 #define NG_NODE_NAME(node)		_NG_NODE_NAME(node)
604 #define NG_NODE_HAS_NAME(node)		_NG_NODE_HAS_NAME(node)
605 #define NG_NODE_ID(node)		_NG_NODE_ID(node)
606 #define	NG_NODE_REF(node)		_NG_NODE_REF(node)
607 #define	NG_NODE_UNREF(node)		_NG_NODE_UNREF(node)
608 #define	NG_NODE_SET_PRIVATE(node, val)	_NG_NODE_SET_PRIVATE(node, val)
609 #define	NG_NODE_PRIVATE(node)		_NG_NODE_PRIVATE(node)
610 #define NG_NODE_IS_VALID(node)		_NG_NODE_IS_VALID(node)
611 #define NG_NODE_NOT_VALID(node)		_NG_NODE_NOT_VALID(node)
612 #define NG_NODE_FORCE_WRITER(node) 	_NG_NODE_FORCE_WRITER(node)
613 #define NG_NODE_HI_STACK(node) 		_NG_NODE_HI_STACK(node)
614 #define NG_NODE_REALLY_DIE(node) 	_NG_NODE_REALLY_DIE(node)
615 #define NG_NODE_NUMHOOKS(node)		_NG_NODE_NUMHOOKS(node)
616 #define NG_NODE_REVIVE(node)		_NG_NODE_REVIVE(node)
617 #define NG_NODE_FOREACH_HOOK(node, fn, arg, rethook)			\
618 		_NG_NODE_FOREACH_HOOK(node, fn, arg, rethook)
619 #endif	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
620 
621 /***********************************************************************
622  ************* Node Queue and Item Structures and Methods **************
623  ***********************************************************************
624  *
625  */
626 typedef	void	ng_item_fn(node_p node, hook_p hook, void *arg1, int arg2);
627 typedef	int	ng_item_fn2(node_p node, struct ng_item *item, hook_p hook);
628 typedef	void	ng_apply_t(void *context, int error);
629 struct ng_apply_info {
630 	ng_apply_t	*apply;
631 	void		*context;
632 	int		refs;
633 	int		error;
634 };
635 struct ng_item {
636 	u_long	el_flags;
637 	STAILQ_ENTRY(ng_item)	el_next;
638 	node_p	el_dest; /* The node it will be applied against (or NULL) */
639 	hook_p	el_hook; /* Entering hook. Optional in Control messages */
640 	union {
641 		struct mbuf	*da_m;
642 		struct {
643 			struct ng_mesg	*msg_msg;
644 			ng_ID_t		msg_retaddr;
645 		} msg;
646 		struct {
647 			union {
648 				ng_item_fn	*fn_fn;
649 				ng_item_fn2	*fn_fn2;
650 			} fn_fn;
651 			void 		*fn_arg1;
652 			int		fn_arg2;
653 		} fn;
654 	} body;
655 	/*
656 	 * Optional callback called when item is being applied,
657 	 * and its context.
658 	 */
659 	struct ng_apply_info	*apply;
660 	u_int	depth;
661 #ifdef	NETGRAPH_DEBUG /*----------------------------------------------*/
662 	char *lastfile;
663 	int  lastline;
664 	TAILQ_ENTRY(ng_item)	  all;		/* all existing items */
665 #endif	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
666 };
667 
668 #define NGQF_TYPE	0x03		/* MASK of content definition */
669 #define NGQF_MESG	0x00		/* the queue element is a message */
670 #define NGQF_DATA	0x01		/* the queue element is data */
671 #define NGQF_FN		0x02		/* the queue element is a function */
672 #define NGQF_FN2	0x03		/* the queue element is a new function */
673 
674 #define NGQF_RW		0x04		/* MASK for wanted queue mode */
675 #define NGQF_READER	0x04		/* wants to be a reader */
676 #define NGQF_WRITER	0x00		/* wants to be a writer */
677 
678 #define NGQF_QMODE	0x08		/* MASK for how it was queued */
679 #define NGQF_QREADER	0x08		/* was queued as a reader */
680 #define NGQF_QWRITER	0x00		/* was queued as a writer */
681 
682 /*
683  * Get the mbuf (etc) out of an item.
684  * Sets the value in the item to NULL in case we need to call NG_FREE_ITEM()
685  * with it, (to avoid freeing the things twice).
686  * If you don't want to zero out the item then realise that the
687  * item still owns it.
688  * Retaddr is different. There are no references on that. It's just a number.
689  * The debug versions must be either all used everywhere or not at all.
690  */
691 
692 #define _NGI_M(i) ((i)->body.da_m)
693 #define _NGI_MSG(i) ((i)->body.msg.msg_msg)
694 #define _NGI_RETADDR(i) ((i)->body.msg.msg_retaddr)
695 #define	_NGI_FN(i) ((i)->body.fn.fn_fn.fn_fn)
696 #define	_NGI_FN2(i) ((i)->body.fn.fn_fn.fn_fn2)
697 #define	_NGI_ARG1(i) ((i)->body.fn.fn_arg1)
698 #define	_NGI_ARG2(i) ((i)->body.fn.fn_arg2)
699 #define	_NGI_NODE(i) ((i)->el_dest)
700 #define	_NGI_HOOK(i) ((i)->el_hook)
701 #define	_NGI_SET_HOOK(i,h) do { _NGI_HOOK(i) = h; h = NULL;} while (0)
702 #define	_NGI_CLR_HOOK(i)   do {						\
703 		hook_p _hook = _NGI_HOOK(i);				\
704 		if (_hook) {						\
705 			_NG_HOOK_UNREF(_hook);				\
706 			_NGI_HOOK(i) = NULL;				\
707 		}							\
708 	} while (0)
709 #define	_NGI_SET_NODE(i,n) do { _NGI_NODE(i) = n; n = NULL;} while (0)
710 #define	_NGI_CLR_NODE(i)   do {						\
711 		node_p _node = _NGI_NODE(i);				\
712 		if (_node) {						\
713 			_NG_NODE_UNREF(_node);				\
714 			_NGI_NODE(i) = NULL;				\
715 		}							\
716 	} while (0)
717 
718 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/
719 void				dumpitem(item_p item, char *file, int line);
720 static __inline void		_ngi_check(item_p item, char *file, int line) ;
721 static __inline struct mbuf **	_ngi_m(item_p item, char *file, int line) ;
722 static __inline ng_ID_t *	_ngi_retaddr(item_p item, char *file, int line);
723 static __inline struct ng_mesg ** _ngi_msg(item_p item, char *file, int line) ;
724 static __inline ng_item_fn **	_ngi_fn(item_p item, char *file, int line) ;
725 static __inline ng_item_fn2 **	_ngi_fn2(item_p item, char *file, int line) ;
726 static __inline void **		_ngi_arg1(item_p item, char *file, int line) ;
727 static __inline int *		_ngi_arg2(item_p item, char *file, int line) ;
728 static __inline node_p		_ngi_node(item_p item, char *file, int line);
729 static __inline hook_p		_ngi_hook(item_p item, char *file, int line);
730 
731 static __inline void
732 _ngi_check(item_p item, char *file, int line)
733 {
734 	(item)->lastline = line;
735 	(item)->lastfile = file;
736 }
737 
738 static __inline struct mbuf **
739 _ngi_m(item_p item, char *file, int line)
740 {
741 	_ngi_check(item, file, line);
742 	return (&_NGI_M(item));
743 }
744 
745 static __inline struct ng_mesg **
746 _ngi_msg(item_p item, char *file, int line)
747 {
748 	_ngi_check(item, file, line);
749 	return (&_NGI_MSG(item));
750 }
751 
752 static __inline ng_ID_t *
753 _ngi_retaddr(item_p item, char *file, int line)
754 {
755 	_ngi_check(item, file, line);
756 	return (&_NGI_RETADDR(item));
757 }
758 
759 static __inline ng_item_fn **
760 _ngi_fn(item_p item, char *file, int line)
761 {
762 	_ngi_check(item, file, line);
763 	return (&_NGI_FN(item));
764 }
765 
766 static __inline ng_item_fn2 **
767 _ngi_fn2(item_p item, char *file, int line)
768 {
769 	_ngi_check(item, file, line);
770 	return (&_NGI_FN2(item));
771 }
772 
773 static __inline void **
774 _ngi_arg1(item_p item, char *file, int line)
775 {
776 	_ngi_check(item, file, line);
777 	return (&_NGI_ARG1(item));
778 }
779 
780 static __inline int *
781 _ngi_arg2(item_p item, char *file, int line)
782 {
783 	_ngi_check(item, file, line);
784 	return (&_NGI_ARG2(item));
785 }
786 
787 static __inline node_p
788 _ngi_node(item_p item, char *file, int line)
789 {
790 	_ngi_check(item, file, line);
791 	return (_NGI_NODE(item));
792 }
793 
794 static __inline hook_p
795 _ngi_hook(item_p item, char *file, int line)
796 {
797 	_ngi_check(item, file, line);
798 	return (_NGI_HOOK(item));
799 }
800 
801 #define NGI_M(i)	(*_ngi_m(i, _NN_))
802 #define NGI_MSG(i)	(*_ngi_msg(i, _NN_))
803 #define NGI_RETADDR(i)	(*_ngi_retaddr(i, _NN_))
804 #define NGI_FN(i)	(*_ngi_fn(i, _NN_))
805 #define NGI_FN2(i)	(*_ngi_fn2(i, _NN_))
806 #define NGI_ARG1(i)	(*_ngi_arg1(i, _NN_))
807 #define NGI_ARG2(i)	(*_ngi_arg2(i, _NN_))
808 #define NGI_HOOK(i)	_ngi_hook(i, _NN_)
809 #define NGI_NODE(i)	_ngi_node(i, _NN_)
810 #define	NGI_SET_HOOK(i,h)						\
811 	do { _ngi_check(i, _NN_); _NGI_SET_HOOK(i, h); } while (0)
812 #define	NGI_CLR_HOOK(i)							\
813 	do { _ngi_check(i, _NN_); _NGI_CLR_HOOK(i); } while (0)
814 #define	NGI_SET_NODE(i,n)						\
815 	do { _ngi_check(i, _NN_); _NGI_SET_NODE(i, n); } while (0)
816 #define	NGI_CLR_NODE(i)							\
817 	do { _ngi_check(i, _NN_); _NGI_CLR_NODE(i); } while (0)
818 
819 #define NG_FREE_ITEM(item)						\
820 	do {								\
821 		_ngi_check(item, _NN_);					\
822 		ng_free_item((item));					\
823 	} while (0)
824 
825 #define	SAVE_LINE(item)							\
826 	do {								\
827 		(item)->lastline = __LINE__;				\
828 		(item)->lastfile = __FILE__;				\
829 	} while (0)
830 
831 #else	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
832 
833 #define NGI_M(i)	_NGI_M(i)
834 #define NGI_MSG(i)	_NGI_MSG(i)
835 #define NGI_RETADDR(i)	_NGI_RETADDR(i)
836 #define NGI_FN(i)	_NGI_FN(i)
837 #define NGI_FN2(i)	_NGI_FN2(i)
838 #define NGI_ARG1(i)	_NGI_ARG1(i)
839 #define NGI_ARG2(i)	_NGI_ARG2(i)
840 #define	NGI_NODE(i)	_NGI_NODE(i)
841 #define	NGI_HOOK(i)	_NGI_HOOK(i)
842 #define	NGI_SET_HOOK(i,h) _NGI_SET_HOOK(i,h)
843 #define	NGI_CLR_HOOK(i)	  _NGI_CLR_HOOK(i)
844 #define	NGI_SET_NODE(i,n) _NGI_SET_NODE(i,n)
845 #define	NGI_CLR_NODE(i)	  _NGI_CLR_NODE(i)
846 
847 #define	NG_FREE_ITEM(item)	ng_free_item((item))
848 #define	SAVE_LINE(item)		do {} while (0)
849 
850 #endif	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
851 
852 #define NGI_GET_M(i,m)							\
853 	do {								\
854 		(m) = NGI_M(i);						\
855 		_NGI_M(i) = NULL;					\
856 	} while (0)
857 
858 #define NGI_GET_MSG(i,m)						\
859 	do {								\
860 		(m) = NGI_MSG(i);					\
861 		_NGI_MSG(i) = NULL;					\
862 	} while (0)
863 
864 #define NGI_GET_NODE(i,n)	/* YOU NOW HAVE THE REFERENCE */	\
865 	do {								\
866 		(n) = NGI_NODE(i);					\
867 		_NGI_NODE(i) = NULL;					\
868 	} while (0)
869 
870 #define NGI_GET_HOOK(i,h)						\
871 	do {								\
872 		(h) = NGI_HOOK(i);					\
873 		_NGI_HOOK(i) = NULL;					\
874 	} while (0)
875 
876 #define NGI_SET_WRITER(i)	((i)->el_flags &= ~NGQF_QMODE)
877 #define NGI_SET_READER(i)	((i)->el_flags |= NGQF_QREADER)
878 
879 #define NGI_QUEUED_READER(i)	((i)->el_flags & NGQF_QREADER)
880 #define NGI_QUEUED_WRITER(i)	(((i)->el_flags & NGQF_QMODE) == NGQF_QWRITER)
881 
882 /**********************************************************************
883 * Data macros.  Send, manipulate and free.
884 **********************************************************************/
885 /*
886  * Assuming the data is already ok, just set the new address and send
887  */
888 #define NG_FWD_ITEM_HOOK_FLAGS(error, item, hook, flags)		\
889 	do {								\
890 		(error) =						\
891 		    ng_address_hook(NULL, (item), (hook), NG_NOFLAGS);	\
892 		if (error == 0) {					\
893 			SAVE_LINE(item);				\
894 			(error) = ng_snd_item((item), (flags));		\
895 		}							\
896 		(item) = NULL;						\
897 	} while (0)
898 #define	NG_FWD_ITEM_HOOK(error, item, hook)	\
899 		NG_FWD_ITEM_HOOK_FLAGS(error, item, hook, NG_NOFLAGS)
900 
901 /*
902  * Forward a data packet. Mbuf pointer is updated to new value. We
903  * presume you dealt with the old one when you update it to the new one
904  * (or it maybe the old one). We got a packet and possibly had to modify
905  * the mbuf. You should probably use NGI_GET_M() if you are going to use
906  * this too.
907  */
908 #define NG_FWD_NEW_DATA_FLAGS(error, item, hook, m, flags)		\
909 	do {								\
910 		NGI_M(item) = (m);					\
911 		(m) = NULL;						\
912 		NG_FWD_ITEM_HOOK_FLAGS(error, item, hook, flags);	\
913 	} while (0)
914 #define	NG_FWD_NEW_DATA(error, item, hook, m)	\
915 		NG_FWD_NEW_DATA_FLAGS(error, item, hook, m, NG_NOFLAGS)
916 
917 /* Send a previously unpackaged mbuf. XXX: This should be called
918  * NG_SEND_DATA in future, but this name is kept for compatibility
919  * reasons.
920  */
921 #define NG_SEND_DATA_FLAGS(error, hook, m, flags)			\
922 	do {								\
923 		item_p _item;						\
924 		if ((_item = ng_package_data((m), flags))) {		\
925 			NG_FWD_ITEM_HOOK_FLAGS(error, _item, hook, flags);\
926 		} else {						\
927 			(error) = ENOMEM;				\
928 		}							\
929 		(m) = NULL;						\
930 	} while (0)
931 
932 #define NG_SEND_DATA_ONLY(error, hook, m)	\
933 		NG_SEND_DATA_FLAGS(error, hook, m, NG_NOFLAGS)
934 /* NG_SEND_DATA() compat for meta-data times */
935 #define	NG_SEND_DATA(error, hook, m, x)	\
936 		NG_SEND_DATA_FLAGS(error, hook, m, NG_NOFLAGS)
937 
938 #define NG_FREE_MSG(msg)						\
939 	do {								\
940 		if ((msg)) {						\
941 			free((msg), M_NETGRAPH_MSG);			\
942 			(msg) = NULL;					\
943 		}	 						\
944 	} while (0)
945 
946 #define NG_FREE_M(m)							\
947 	do {								\
948 		if ((m)) {						\
949 			m_freem((m));					\
950 			(m) = NULL;					\
951 		}							\
952 	} while (0)
953 
954 /*****************************************
955 * Message macros
956 *****************************************/
957 
958 #define NG_SEND_MSG_HOOK(error, here, msg, hook, retaddr)		\
959 	do {								\
960 		item_p _item;						\
961 		if ((_item = ng_package_msg(msg, NG_NOFLAGS)) == NULL) {\
962 			(msg) = NULL;					\
963 			(error) = ENOMEM;				\
964 			break;						\
965 		}							\
966 		if (((error) = ng_address_hook((here), (_item),		\
967 					(hook), (retaddr))) == 0) {	\
968 			SAVE_LINE(_item);				\
969 			(error) = ng_snd_item((_item), 0);		\
970 		}							\
971 		(msg) = NULL;						\
972 	} while (0)
973 
974 #define NG_SEND_MSG_PATH(error, here, msg, path, retaddr)		\
975 	do {								\
976 		item_p _item;						\
977 		if ((_item = ng_package_msg(msg, NG_NOFLAGS)) == NULL) {\
978 			(msg) = NULL;					\
979 			(error) = ENOMEM;				\
980 			break;						\
981 		}							\
982 		if (((error) = ng_address_path((here), (_item),		\
983 					(path), (retaddr))) == 0) {	\
984 			SAVE_LINE(_item);				\
985 			(error) = ng_snd_item((_item), 0);		\
986 		}							\
987 		(msg) = NULL;						\
988 	} while (0)
989 
990 #define NG_SEND_MSG_ID(error, here, msg, ID, retaddr)			\
991 	do {								\
992 		item_p _item;						\
993 		if ((_item = ng_package_msg(msg, NG_NOFLAGS)) == NULL) {\
994 			(msg) = NULL;					\
995 			(error) = ENOMEM;				\
996 			break;						\
997 		}							\
998 		if (((error) = ng_address_ID((here), (_item),		\
999 					(ID), (retaddr))) == 0) {	\
1000 			SAVE_LINE(_item);				\
1001 			(error) = ng_snd_item((_item), 0);		\
1002 		}							\
1003 		(msg) = NULL;						\
1004 	} while (0)
1005 
1006 /*
1007  * Redirect the message to the next hop using the given hook.
1008  * ng_retarget_msg() frees the item if there is an error
1009  * and returns an error code.  It returns 0 on success.
1010  */
1011 #define NG_FWD_MSG_HOOK(error, here, item, hook, retaddr)		\
1012 	do {								\
1013 		if (((error) = ng_address_hook((here), (item),		\
1014 					(hook), (retaddr))) == 0) {	\
1015 			SAVE_LINE(item);				\
1016 			(error) = ng_snd_item((item), 0);		\
1017 		}							\
1018 		(item) = NULL;						\
1019 	} while (0)
1020 
1021 /*
1022  * Send a queue item back to it's originator with a response message.
1023  * Assume original message was removed and freed separatly.
1024  */
1025 #define NG_RESPOND_MSG(error, here, item, resp)				\
1026 	do {								\
1027 		if (resp) {						\
1028 			ng_ID_t _dest = NGI_RETADDR(item);		\
1029 			NGI_RETADDR(item) = 0;				\
1030 			NGI_MSG(item) = resp;				\
1031 			if ((error = ng_address_ID((here), (item),	\
1032 					_dest, 0)) == 0) {		\
1033 				SAVE_LINE(item);			\
1034 				(error) = ng_snd_item((item), NG_QUEUE);\
1035 			}						\
1036 		} else							\
1037 			NG_FREE_ITEM(item);				\
1038 		(item) = NULL;						\
1039 	} while (0)
1040 
1041 /***********************************************************************
1042  ******** Structures Definitions and Macros for defining a node  *******
1043  ***********************************************************************
1044  *
1045  * Here we define the structures needed to actually define a new node
1046  * type.
1047  */
1048 
1049 /*
1050  * Command list -- each node type specifies the command that it knows
1051  * how to convert between ASCII and binary using an array of these.
1052  * The last element in the array must be a terminator with cookie=0.
1053  */
1054 
1055 struct ng_cmdlist {
1056 	u_int32_t			cookie;		/* command typecookie */
1057 	int				cmd;		/* command number */
1058 	const char			*name;		/* command name */
1059 	const struct ng_parse_type	*mesgType;	/* args if !NGF_RESP */
1060 	const struct ng_parse_type	*respType;	/* args if NGF_RESP */
1061 };
1062 
1063 /*
1064  * Structure of a node type
1065  * If data is sent to the "rcvdata()" entrypoint then the system
1066  * may decide to defer it until later by queing it with the normal netgraph
1067  * input queuing system.  This is decidde by the HK_QUEUE flag being set in
1068  * the flags word of the peer (receiving) hook. The dequeuing mechanism will
1069  * ensure it is not requeued again.
1070  * Note the input queueing system is to allow modules
1071  * to 'release the stack' or to pass data across spl layers.
1072  * The data will be redelivered as soon as the NETISR code runs
1073  * which may be almost immediately.  A node may also do it's own queueing
1074  * for other reasons (e.g. device output queuing).
1075  */
1076 struct ng_type {
1077 	u_int32_t	version; 	/* must equal NG_API_VERSION */
1078 	const char	*name;		/* Unique type name */
1079 	modeventhand_t	mod_event;	/* Module event handler (optional) */
1080 	ng_constructor_t *constructor;	/* Node constructor */
1081 	ng_rcvmsg_t	*rcvmsg;	/* control messages come here */
1082 	ng_close_t	*close;		/* warn about forthcoming shutdown */
1083 	ng_shutdown_t	*shutdown;	/* reset, and free resources */
1084 	ng_newhook_t	*newhook;	/* first notification of new hook */
1085 	ng_findhook_t	*findhook;	/* only if you have lots of hooks */
1086 	ng_connect_t	*connect;	/* final notification of new hook */
1087 	ng_rcvdata_t	*rcvdata;	/* data comes here */
1088 	ng_disconnect_t	*disconnect;	/* notify on disconnect */
1089 
1090 	const struct	ng_cmdlist *cmdlist;	/* commands we can convert */
1091 
1092 	/* R/W data private to the base netgraph code DON'T TOUCH! */
1093 	LIST_ENTRY(ng_type) types;		/* linked list of all types */
1094 	int		    refs;		/* number of instances */
1095 };
1096 
1097 /*
1098  * Use the NETGRAPH_INIT() macro to link a node type into the
1099  * netgraph system. This works for types compiled into the kernel
1100  * as well as KLD modules. The first argument should be the type
1101  * name (eg, echo) and the second a pointer to the type struct.
1102  *
1103  * If a different link time is desired, e.g., a device driver that
1104  * needs to install its netgraph type before probing, use the
1105  * NETGRAPH_INIT_ORDERED() macro instead.  Device drivers probably
1106  * want to use SI_SUB_DRIVERS/SI_ORDER_FIRST.
1107  */
1108 
1109 #define NETGRAPH_INIT_ORDERED(typename, typestructp, sub, order)	\
1110 static moduledata_t ng_##typename##_mod = {				\
1111 	"ng_" #typename,						\
1112 	ng_mod_event,							\
1113 	(typestructp)							\
1114 };									\
1115 DECLARE_MODULE(ng_##typename, ng_##typename##_mod, sub, order);		\
1116 MODULE_DEPEND(ng_##typename, netgraph,	NG_ABI_VERSION,			\
1117 					NG_ABI_VERSION,			\
1118 					NG_ABI_VERSION)
1119 
1120 #define NETGRAPH_INIT(tn, tp)						\
1121 	NETGRAPH_INIT_ORDERED(tn, tp, SI_SUB_PSEUDO, SI_ORDER_MIDDLE)
1122 
1123 /* Special malloc() type for netgraph structs and ctrl messages */
1124 /* Only these two types should be visible to nodes */
1125 MALLOC_DECLARE(M_NETGRAPH);
1126 MALLOC_DECLARE(M_NETGRAPH_MSG);
1127 
1128 /* declare the base of the netgraph sysclt hierarchy */
1129 /* but only if this file cares about sysctls */
1130 #ifdef	SYSCTL_DECL
1131 SYSCTL_DECL(_net_graph);
1132 #endif
1133 
1134 /*
1135  * Methods that the nodes can use.
1136  * Many of these methods should usually NOT be used directly but via
1137  * Macros above.
1138  */
1139 int	ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr);
1140 int	ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr);
1141 int	ng_address_path(node_p here, item_p item, const char *address, ng_ID_t raddr);
1142 int	ng_bypass(hook_p hook1, hook_p hook2);
1143 hook_p	ng_findhook(node_p node, const char *name);
1144 struct	ng_type *ng_findtype(const char *type);
1145 int	ng_make_node_common(struct ng_type *typep, node_p *nodep);
1146 int	ng_name_node(node_p node, const char *name);
1147 node_p	ng_name2noderef(node_p node, const char *name);
1148 int	ng_newtype(struct ng_type *tp);
1149 ng_ID_t ng_node2ID(node_cp node);
1150 item_p	ng_package_data(struct mbuf *m, int flags);
1151 item_p	ng_package_msg(struct ng_mesg *msg, int flags);
1152 item_p	ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg);
1153 void	ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr);
1154 int	ng_rmhook_self(hook_p hook);	/* if a node wants to kill a hook */
1155 int	ng_rmnode_self(node_p here);	/* if a node wants to suicide */
1156 int	ng_rmtype(struct ng_type *tp);
1157 int	ng_snd_item(item_p item, int queue);
1158 int 	ng_send_fn(node_p node, hook_p hook, ng_item_fn *fn, void *arg1,
1159 	int arg2);
1160 int 	ng_send_fn1(node_p node, hook_p hook, ng_item_fn *fn, void *arg1,
1161 	int arg2, int flags);
1162 int 	ng_send_fn2(node_p node, hook_p hook, item_p pitem, ng_item_fn2 *fn,
1163 	void *arg1, int arg2, int flags);
1164 int	ng_uncallout(struct callout *c, node_p node);
1165 int	ng_callout(struct callout *c, node_p node, hook_p hook, int ticks,
1166 	    ng_item_fn *fn, void * arg1, int arg2);
1167 #define	ng_callout_init(c)	callout_init(c, 1)
1168 
1169 /* Flags for netgraph functions. */
1170 #define	NG_NOFLAGS	0x00000000	/* no special options */
1171 #define	NG_QUEUE	0x00000001	/* enqueue item, don't dispatch */
1172 #define	NG_WAITOK	0x00000002	/* use M_WAITOK, etc. */
1173 /* XXXGL: NG_PROGRESS unused since ng_base.c rev. 1.136. Should be deleted? */
1174 #define	NG_PROGRESS	0x00000004	/* return EINPROGRESS if queued */
1175 #define	NG_REUSE_ITEM	0x00000008	/* supplied item should be reused */
1176 
1177 /*
1178  * prototypes the user should DEFINITELY not use directly
1179  */
1180 void	ng_free_item(item_p item); /* Use NG_FREE_ITEM instead */
1181 int	ng_mod_event(module_t mod, int what, void *arg);
1182 
1183 /*
1184  * Tag definitions and constants
1185  */
1186 
1187 #define	NG_TAG_PRIO	1
1188 
1189 struct ng_tag_prio {
1190 	struct m_tag	tag;
1191 	char	priority;
1192 	char	discardability;
1193 };
1194 
1195 #define	NG_PRIO_CUTOFF		32
1196 #define	NG_PRIO_LINKSTATE	64
1197 
1198 /* Macros and declarations to keep compatibility with metadata, which
1199  * is obsoleted now. To be deleted.
1200  */
1201 typedef void *meta_p;
1202 #define _NGI_META(i)	NULL
1203 #define NGI_META(i)	NULL
1204 #define NG_FREE_META(meta)
1205 #define NGI_GET_META(i,m)
1206 #define	ng_copy_meta(meta) NULL
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