xref: /freebsd/sys/netgraph/netgraph.h (revision 3cbb4cc200f8a0ad7ed08233425ea54524a21f1c)
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 
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 dependent 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 ");
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 #define	NG_HOOK_REF(hook)		_ng_hook_ref(hook, _NN_)
306 #define NG_HOOK_NAME(hook)		_ng_hook_name(hook, _NN_)
307 #define NG_HOOK_UNREF(hook)		_ng_hook_unref(hook, _NN_)
308 #define	NG_HOOK_SET_PRIVATE(hook, val)	_ng_hook_set_private(hook, val, _NN_)
309 #define	NG_HOOK_SET_RCVMSG(hook, val)	_ng_hook_set_rcvmsg(hook, val, _NN_)
310 #define	NG_HOOK_SET_RCVDATA(hook, val)	_ng_hook_set_rcvdata(hook, val, _NN_)
311 #define	NG_HOOK_PRIVATE(hook)		_ng_hook_private(hook, _NN_)
312 #define NG_HOOK_NOT_VALID(hook)		_ng_hook_not_valid(hook, _NN_)
313 #define NG_HOOK_IS_VALID(hook)		_ng_hook_is_valid(hook, _NN_)
314 #define NG_HOOK_NODE(hook)		_ng_hook_node(hook, _NN_)
315 #define NG_HOOK_PEER(hook)		_ng_hook_peer(hook, _NN_)
316 #define NG_HOOK_FORCE_WRITER(hook)	_ng_hook_force_writer(hook, _NN_)
317 #define NG_HOOK_FORCE_QUEUE(hook)	_ng_hook_force_queue(hook, _NN_)
318 #define NG_HOOK_SET_TO_INBOUND(hook)	_ng_hook_set_to_inbound(hook, _NN_)
319 #define NG_HOOK_HI_STACK(hook)		_ng_hook_hi_stack(hook, _NN_)
320 
321 #else	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
322 
323 #define	NG_HOOK_REF(hook)		_NG_HOOK_REF(hook)
324 #define NG_HOOK_NAME(hook)		_NG_HOOK_NAME(hook)
325 #define NG_HOOK_UNREF(hook)		_NG_HOOK_UNREF(hook)
326 #define	NG_HOOK_SET_PRIVATE(hook, val)	_NG_HOOK_SET_PRIVATE(hook, val)
327 #define	NG_HOOK_SET_RCVMSG(hook, val)	_NG_HOOK_SET_RCVMSG(hook, val)
328 #define	NG_HOOK_SET_RCVDATA(hook, val)	_NG_HOOK_SET_RCVDATA(hook, val)
329 #define	NG_HOOK_PRIVATE(hook)		_NG_HOOK_PRIVATE(hook)
330 #define NG_HOOK_NOT_VALID(hook)		_NG_HOOK_NOT_VALID(hook)
331 #define NG_HOOK_IS_VALID(hook)		_NG_HOOK_IS_VALID(hook)
332 #define NG_HOOK_NODE(hook)		_NG_HOOK_NODE(hook)
333 #define NG_HOOK_PEER(hook)		_NG_HOOK_PEER(hook)
334 #define NG_HOOK_FORCE_WRITER(hook)	_NG_HOOK_FORCE_WRITER(hook)
335 #define NG_HOOK_FORCE_QUEUE(hook)	_NG_HOOK_FORCE_QUEUE(hook)
336 #define NG_HOOK_SET_TO_INBOUND(hook)	_NG_HOOK_SET_TO_INBOUND(hook)
337 #define NG_HOOK_HI_STACK(hook)		_NG_HOOK_HI_STACK(hook)
338 
339 #endif	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
340 
341 /***********************************************************************
342  ***************** Node Structure and Methods **************************
343  ***********************************************************************
344  * Structure of a node
345  * including the eembedded queue structure.
346  *
347  * The structure for queueing Netgraph request items
348  * embedded in the node structure
349  */
350 struct ng_queue {
351 	u_int		q_flags;	/* Current r/w/q lock flags */
352 	u_int		q_flags2;	/* Other queue flags */
353 	struct mtx	q_mtx;
354 	STAILQ_ENTRY(ng_node)	q_work;	/* nodes with work to do */
355 	STAILQ_HEAD(, ng_item)	queue;	/* actually items queue */
356 };
357 
358 struct ng_node {
359 	char	nd_name[NG_NODESIZ];	/* optional globally unique name */
360 	struct	ng_type *nd_type;	/* the installed 'type' */
361 	int	nd_flags;		/* see below for bit definitions */
362 	int	nd_numhooks;		/* number of hooks */
363 	void   *nd_private;		/* node type dependent node ID */
364 	ng_ID_t	nd_ID;			/* Unique per node */
365 	LIST_HEAD(hooks, ng_hook) nd_hooks;	/* linked list of node hooks */
366 	LIST_ENTRY(ng_node)	  nd_nodes;	/* name hash collision list */
367 	LIST_ENTRY(ng_node)	  nd_idnodes;	/* ID hash collision list */
368 	struct	ng_queue	  nd_input_queue; /* input queue for locking */
369 	int	nd_refs;		/* # of references to this node */
370 	struct	vnet		 *nd_vnet;	/* network stack instance */
371 #ifdef	NETGRAPH_DEBUG /*----------------------------------------------*/
372 #define ND_MAGIC 0x59264837
373 	int	nd_magic;
374 	char	*lastfile;
375 	int	lastline;
376 	SLIST_ENTRY(ng_node)	  nd_all;	/* all existing nodes */
377 #endif	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
378 };
379 
380 /* Flags for a node */
381 #define NGF_INVALID	0x00000001	/* free when refs go to 0 */
382 #define NG_INVALID	NGF_INVALID	/* compat for old code */
383 #define NGF_FORCE_WRITER	0x00000004	/* Never multithread this node */
384 #define NG_FORCE_WRITER	NGF_FORCE_WRITER /* compat for old code */
385 #define NGF_CLOSING	0x00000008	/* ng_rmnode() at work */
386 #define NG_CLOSING	NGF_CLOSING	/* compat for old code */
387 #define NGF_REALLY_DIE	0x00000010	/* "persistent" node is unloading */
388 #define NG_REALLY_DIE	NGF_REALLY_DIE	/* compat for old code */
389 #define NGF_HI_STACK	0x00000020	/* node has hi stack usage */
390 #define NGF_TYPE1	0x10000000	/* reserved for type specific storage */
391 #define NGF_TYPE2	0x20000000	/* reserved for type specific storage */
392 #define NGF_TYPE3	0x40000000	/* reserved for type specific storage */
393 #define NGF_TYPE4	0x80000000	/* reserved for type specific storage */
394 
395 /*
396  * Public methods for nodes.
397  * If you can't do it with these you probably shouldn't be doing it.
398  */
399 void	ng_unref_node(node_p node); /* don't move this */
400 #define _NG_NODE_NAME(node)	((node)->nd_name + 0)
401 #define _NG_NODE_HAS_NAME(node)	((node)->nd_name[0] + 0)
402 #define _NG_NODE_ID(node)	((node)->nd_ID + 0)
403 #define	_NG_NODE_REF(node)	refcount_acquire(&(node)->nd_refs)
404 #define	_NG_NODE_UNREF(node)	ng_unref_node(node)
405 #define	_NG_NODE_SET_PRIVATE(node, val)	do {(node)->nd_private = val;} while (0)
406 #define	_NG_NODE_PRIVATE(node)	((node)->nd_private)
407 #define _NG_NODE_IS_VALID(node)	(!((node)->nd_flags & NGF_INVALID))
408 #define _NG_NODE_NOT_VALID(node)	((node)->nd_flags & NGF_INVALID)
409 #define _NG_NODE_NUMHOOKS(node)	((node)->nd_numhooks + 0) /* rvalue */
410 #define _NG_NODE_FORCE_WRITER(node)					\
411 	do{ node->nd_flags |= NGF_FORCE_WRITER; }while (0)
412 #define _NG_NODE_HI_STACK(node)						\
413 	do{ node->nd_flags |= NGF_HI_STACK; }while (0)
414 #define _NG_NODE_REALLY_DIE(node)					\
415 	do{ node->nd_flags |= (NGF_REALLY_DIE|NGF_INVALID); }while (0)
416 #define _NG_NODE_REVIVE(node) \
417 	do { node->nd_flags &= ~NGF_INVALID; } while (0)
418 /*
419  * The hook iterator.
420  * This macro will call a function of type ng_fn_eachhook for each
421  * hook attached to the node. If the function returns 0, then the
422  * iterator will stop and return a pointer to the hook that returned 0.
423  */
424 typedef	int	ng_fn_eachhook(hook_p hook, void* arg);
425 #define _NG_NODE_FOREACH_HOOK(node, fn, arg, rethook)			\
426 	do {								\
427 		hook_p _hook;						\
428 		(rethook) = NULL;					\
429 		LIST_FOREACH(_hook, &((node)->nd_hooks), hk_hooks) {	\
430 			if ((fn)(_hook, arg) == 0) {			\
431 				(rethook) = _hook;			\
432 				break;					\
433 			}						\
434 		}							\
435 	} while (0)
436 
437 #ifdef	NETGRAPH_DEBUG /*----------------------------------------------*/
438 void	dumpnode(node_p node, char *file, int line);
439 static __inline void _chknode(node_p node, char *file, int line);
440 static __inline char * _ng_node_name(node_p node, char *file, int line);
441 static __inline int _ng_node_has_name(node_p node, char *file, int line);
442 static __inline ng_ID_t _ng_node_id(node_p node, char *file, int line);
443 static __inline void _ng_node_ref(node_p node, char *file, int line);
444 static __inline void _ng_node_unref(node_p node, char *file, int line);
445 static __inline void _ng_node_set_private(node_p node, void * val,
446 							char *file, int line);
447 static __inline void * _ng_node_private(node_p node, char *file, int line);
448 static __inline int _ng_node_is_valid(node_p node, char *file, int line);
449 static __inline int _ng_node_not_valid(node_p node, char *file, int line);
450 static __inline int _ng_node_numhooks(node_p node, char *file, int line);
451 static __inline void _ng_node_force_writer(node_p node, char *file, int line);
452 static __inline hook_p _ng_node_foreach_hook(node_p node,
453 			ng_fn_eachhook *fn, void *arg, char *file, int line);
454 static __inline void _ng_node_revive(node_p node, char *file, int line);
455 
456 static __inline void
457 _chknode(node_p node, char *file, int line)
458 {
459 	if (node->nd_magic != ND_MAGIC) {
460 		printf("Accessing freed ");
461 		dumpnode(node, file, line);
462 	}
463 	node->lastline = line;
464 	node->lastfile = file;
465 }
466 
467 static __inline char *
468 _ng_node_name(node_p node, char *file, int line)
469 {
470 	_chknode(node, file, line);
471 	return(_NG_NODE_NAME(node));
472 }
473 
474 static __inline int
475 _ng_node_has_name(node_p node, char *file, int line)
476 {
477 	_chknode(node, file, line);
478 	return(_NG_NODE_HAS_NAME(node));
479 }
480 
481 static __inline ng_ID_t
482 _ng_node_id(node_p node, char *file, int line)
483 {
484 	_chknode(node, file, line);
485 	return(_NG_NODE_ID(node));
486 }
487 
488 static __inline void
489 _ng_node_ref(node_p node, char *file, int line)
490 {
491 	_chknode(node, file, line);
492 	_NG_NODE_REF(node);
493 }
494 
495 static __inline void
496 _ng_node_unref(node_p node, char *file, int line)
497 {
498 	_chknode(node, file, line);
499 	_NG_NODE_UNREF(node);
500 }
501 
502 static __inline void
503 _ng_node_set_private(node_p node, void * val, char *file, int line)
504 {
505 	_chknode(node, file, line);
506 	_NG_NODE_SET_PRIVATE(node, val);
507 }
508 
509 static __inline void *
510 _ng_node_private(node_p node, char *file, int line)
511 {
512 	_chknode(node, file, line);
513 	return (_NG_NODE_PRIVATE(node));
514 }
515 
516 static __inline int
517 _ng_node_is_valid(node_p node, char *file, int line)
518 {
519 	_chknode(node, file, line);
520 	return(_NG_NODE_IS_VALID(node));
521 }
522 
523 static __inline int
524 _ng_node_not_valid(node_p node, char *file, int line)
525 {
526 	_chknode(node, file, line);
527 	return(_NG_NODE_NOT_VALID(node));
528 }
529 
530 static __inline int
531 _ng_node_numhooks(node_p node, char *file, int line)
532 {
533 	_chknode(node, file, line);
534 	return(_NG_NODE_NUMHOOKS(node));
535 }
536 
537 static __inline void
538 _ng_node_force_writer(node_p node, char *file, int line)
539 {
540 	_chknode(node, file, line);
541 	_NG_NODE_FORCE_WRITER(node);
542 }
543 
544 static __inline void
545 _ng_node_hi_stack(node_p node, char *file, int line)
546 {
547 	_chknode(node, file, line);
548 	_NG_NODE_HI_STACK(node);
549 }
550 
551 static __inline void
552 _ng_node_really_die(node_p node, char *file, int line)
553 {
554 	_chknode(node, file, line);
555 	_NG_NODE_REALLY_DIE(node);
556 }
557 
558 static __inline void
559 _ng_node_revive(node_p node, char *file, int line)
560 {
561 	_chknode(node, file, line);
562 	_NG_NODE_REVIVE(node);
563 }
564 
565 static __inline hook_p
566 _ng_node_foreach_hook(node_p node, ng_fn_eachhook *fn, void *arg,
567 						char *file, int line)
568 {
569 	hook_p hook;
570 	_chknode(node, file, line);
571 	_NG_NODE_FOREACH_HOOK(node, fn, arg, hook);
572 	return (hook);
573 }
574 
575 #define NG_NODE_NAME(node)		_ng_node_name(node, _NN_)
576 #define NG_NODE_HAS_NAME(node)		_ng_node_has_name(node, _NN_)
577 #define NG_NODE_ID(node)		_ng_node_id(node, _NN_)
578 #define NG_NODE_REF(node)		_ng_node_ref(node, _NN_)
579 #define	NG_NODE_UNREF(node)		_ng_node_unref(node, _NN_)
580 #define	NG_NODE_SET_PRIVATE(node, val)	_ng_node_set_private(node, val, _NN_)
581 #define	NG_NODE_PRIVATE(node)		_ng_node_private(node, _NN_)
582 #define NG_NODE_IS_VALID(node)		_ng_node_is_valid(node, _NN_)
583 #define NG_NODE_NOT_VALID(node)		_ng_node_not_valid(node, _NN_)
584 #define NG_NODE_FORCE_WRITER(node) 	_ng_node_force_writer(node, _NN_)
585 #define NG_NODE_HI_STACK(node) 		_ng_node_hi_stack(node, _NN_)
586 #define NG_NODE_REALLY_DIE(node) 	_ng_node_really_die(node, _NN_)
587 #define NG_NODE_NUMHOOKS(node)		_ng_node_numhooks(node, _NN_)
588 #define NG_NODE_REVIVE(node)		_ng_node_revive(node, _NN_)
589 #define NG_NODE_FOREACH_HOOK(node, fn, arg, rethook)			      \
590 	do {								      \
591 		rethook = _ng_node_foreach_hook(node, fn, (void *)arg, _NN_); \
592 	} while (0)
593 
594 #else	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
595 
596 #define NG_NODE_NAME(node)		_NG_NODE_NAME(node)
597 #define NG_NODE_HAS_NAME(node)		_NG_NODE_HAS_NAME(node)
598 #define NG_NODE_ID(node)		_NG_NODE_ID(node)
599 #define	NG_NODE_REF(node)		_NG_NODE_REF(node)
600 #define	NG_NODE_UNREF(node)		_NG_NODE_UNREF(node)
601 #define	NG_NODE_SET_PRIVATE(node, val)	_NG_NODE_SET_PRIVATE(node, val)
602 #define	NG_NODE_PRIVATE(node)		_NG_NODE_PRIVATE(node)
603 #define NG_NODE_IS_VALID(node)		_NG_NODE_IS_VALID(node)
604 #define NG_NODE_NOT_VALID(node)		_NG_NODE_NOT_VALID(node)
605 #define NG_NODE_FORCE_WRITER(node) 	_NG_NODE_FORCE_WRITER(node)
606 #define NG_NODE_HI_STACK(node) 		_NG_NODE_HI_STACK(node)
607 #define NG_NODE_REALLY_DIE(node) 	_NG_NODE_REALLY_DIE(node)
608 #define NG_NODE_NUMHOOKS(node)		_NG_NODE_NUMHOOKS(node)
609 #define NG_NODE_REVIVE(node)		_NG_NODE_REVIVE(node)
610 #define NG_NODE_FOREACH_HOOK(node, fn, arg, rethook)			\
611 		_NG_NODE_FOREACH_HOOK(node, fn, arg, rethook)
612 #endif	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
613 
614 /***********************************************************************
615  ************* Node Queue and Item Structures and Methods **************
616  ***********************************************************************
617  *
618  */
619 typedef	void	ng_item_fn(node_p node, hook_p hook, void *arg1, int arg2);
620 typedef	int	ng_item_fn2(node_p node, struct ng_item *item, hook_p hook);
621 typedef	void	ng_apply_t(void *context, int error);
622 struct ng_apply_info {
623 	ng_apply_t	*apply;
624 	void		*context;
625 	int		refs;
626 	int		error;
627 };
628 struct ng_item {
629 	u_long	el_flags;
630 	STAILQ_ENTRY(ng_item)	el_next;
631 	node_p	el_dest; /* The node it will be applied against (or NULL) */
632 	hook_p	el_hook; /* Entering hook. Optional in Control messages */
633 	union {
634 		struct mbuf	*da_m;
635 		struct {
636 			struct ng_mesg	*msg_msg;
637 			ng_ID_t		msg_retaddr;
638 		} msg;
639 		struct {
640 			union {
641 				ng_item_fn	*fn_fn;
642 				ng_item_fn2	*fn_fn2;
643 			} fn_fn;
644 			void 		*fn_arg1;
645 			int		fn_arg2;
646 		} fn;
647 	} body;
648 	/*
649 	 * Optional callback called when item is being applied,
650 	 * and its context.
651 	 */
652 	struct ng_apply_info	*apply;
653 	u_int	depth;
654 #ifdef	NETGRAPH_DEBUG /*----------------------------------------------*/
655 	char *lastfile;
656 	int  lastline;
657 	TAILQ_ENTRY(ng_item)	  all;		/* all existing items */
658 #endif	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
659 };
660 
661 #define NGQF_TYPE	0x03		/* MASK of content definition */
662 #define NGQF_MESG	0x00		/* the queue element is a message */
663 #define NGQF_DATA	0x01		/* the queue element is data */
664 #define NGQF_FN		0x02		/* the queue element is a function */
665 #define NGQF_FN2	0x03		/* the queue element is a new function */
666 
667 #define NGQF_RW		0x04		/* MASK for wanted queue mode */
668 #define NGQF_READER	0x04		/* wants to be a reader */
669 #define NGQF_WRITER	0x00		/* wants to be a writer */
670 
671 #define NGQF_QMODE	0x08		/* MASK for how it was queued */
672 #define NGQF_QREADER	0x08		/* was queued as a reader */
673 #define NGQF_QWRITER	0x00		/* was queued as a writer */
674 
675 /*
676  * Get the mbuf (etc) out of an item.
677  * Sets the value in the item to NULL in case we need to call NG_FREE_ITEM()
678  * with it, (to avoid freeing the things twice).
679  * If you don't want to zero out the item then realise that the
680  * item still owns it.
681  * Retaddr is different. There are no references on that. It's just a number.
682  * The debug versions must be either all used everywhere or not at all.
683  */
684 
685 #define _NGI_M(i) ((i)->body.da_m)
686 #define _NGI_MSG(i) ((i)->body.msg.msg_msg)
687 #define _NGI_RETADDR(i) ((i)->body.msg.msg_retaddr)
688 #define	_NGI_FN(i) ((i)->body.fn.fn_fn.fn_fn)
689 #define	_NGI_FN2(i) ((i)->body.fn.fn_fn.fn_fn2)
690 #define	_NGI_ARG1(i) ((i)->body.fn.fn_arg1)
691 #define	_NGI_ARG2(i) ((i)->body.fn.fn_arg2)
692 #define	_NGI_NODE(i) ((i)->el_dest)
693 #define	_NGI_HOOK(i) ((i)->el_hook)
694 #define	_NGI_SET_HOOK(i,h) do { _NGI_HOOK(i) = h; h = NULL;} while (0)
695 #define	_NGI_CLR_HOOK(i)   do {						\
696 		hook_p _hook = _NGI_HOOK(i);				\
697 		if (_hook) {						\
698 			_NG_HOOK_UNREF(_hook);				\
699 			_NGI_HOOK(i) = NULL;				\
700 		}							\
701 	} while (0)
702 #define	_NGI_SET_NODE(i,n) do { _NGI_NODE(i) = n; n = NULL;} while (0)
703 #define	_NGI_CLR_NODE(i)   do {						\
704 		node_p _node = _NGI_NODE(i);				\
705 		if (_node) {						\
706 			_NG_NODE_UNREF(_node);				\
707 			_NGI_NODE(i) = NULL;				\
708 		}							\
709 	} while (0)
710 
711 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/
712 void				dumpitem(item_p item, char *file, int line);
713 static __inline void		_ngi_check(item_p item, char *file, int line) ;
714 static __inline struct mbuf **	_ngi_m(item_p item, char *file, int line) ;
715 static __inline ng_ID_t *	_ngi_retaddr(item_p item, char *file, int line);
716 static __inline struct ng_mesg ** _ngi_msg(item_p item, char *file, int line) ;
717 static __inline ng_item_fn **	_ngi_fn(item_p item, char *file, int line) ;
718 static __inline ng_item_fn2 **	_ngi_fn2(item_p item, char *file, int line) ;
719 static __inline void **		_ngi_arg1(item_p item, char *file, int line) ;
720 static __inline int *		_ngi_arg2(item_p item, char *file, int line) ;
721 static __inline node_p		_ngi_node(item_p item, char *file, int line);
722 static __inline hook_p		_ngi_hook(item_p item, char *file, int line);
723 
724 static __inline void
725 _ngi_check(item_p item, char *file, int line)
726 {
727 	(item)->lastline = line;
728 	(item)->lastfile = file;
729 }
730 
731 static __inline struct mbuf **
732 _ngi_m(item_p item, char *file, int line)
733 {
734 	_ngi_check(item, file, line);
735 	return (&_NGI_M(item));
736 }
737 
738 static __inline struct ng_mesg **
739 _ngi_msg(item_p item, char *file, int line)
740 {
741 	_ngi_check(item, file, line);
742 	return (&_NGI_MSG(item));
743 }
744 
745 static __inline ng_ID_t *
746 _ngi_retaddr(item_p item, char *file, int line)
747 {
748 	_ngi_check(item, file, line);
749 	return (&_NGI_RETADDR(item));
750 }
751 
752 static __inline ng_item_fn **
753 _ngi_fn(item_p item, char *file, int line)
754 {
755 	_ngi_check(item, file, line);
756 	return (&_NGI_FN(item));
757 }
758 
759 static __inline ng_item_fn2 **
760 _ngi_fn2(item_p item, char *file, int line)
761 {
762 	_ngi_check(item, file, line);
763 	return (&_NGI_FN2(item));
764 }
765 
766 static __inline void **
767 _ngi_arg1(item_p item, char *file, int line)
768 {
769 	_ngi_check(item, file, line);
770 	return (&_NGI_ARG1(item));
771 }
772 
773 static __inline int *
774 _ngi_arg2(item_p item, char *file, int line)
775 {
776 	_ngi_check(item, file, line);
777 	return (&_NGI_ARG2(item));
778 }
779 
780 static __inline node_p
781 _ngi_node(item_p item, char *file, int line)
782 {
783 	_ngi_check(item, file, line);
784 	return (_NGI_NODE(item));
785 }
786 
787 static __inline hook_p
788 _ngi_hook(item_p item, char *file, int line)
789 {
790 	_ngi_check(item, file, line);
791 	return (_NGI_HOOK(item));
792 }
793 
794 #define NGI_M(i)	(*_ngi_m(i, _NN_))
795 #define NGI_MSG(i)	(*_ngi_msg(i, _NN_))
796 #define NGI_RETADDR(i)	(*_ngi_retaddr(i, _NN_))
797 #define NGI_FN(i)	(*_ngi_fn(i, _NN_))
798 #define NGI_FN2(i)	(*_ngi_fn2(i, _NN_))
799 #define NGI_ARG1(i)	(*_ngi_arg1(i, _NN_))
800 #define NGI_ARG2(i)	(*_ngi_arg2(i, _NN_))
801 #define NGI_HOOK(i)	_ngi_hook(i, _NN_)
802 #define NGI_NODE(i)	_ngi_node(i, _NN_)
803 #define	NGI_SET_HOOK(i,h)						\
804 	do { _ngi_check(i, _NN_); _NGI_SET_HOOK(i, h); } while (0)
805 #define	NGI_CLR_HOOK(i)							\
806 	do { _ngi_check(i, _NN_); _NGI_CLR_HOOK(i); } while (0)
807 #define	NGI_SET_NODE(i,n)						\
808 	do { _ngi_check(i, _NN_); _NGI_SET_NODE(i, n); } while (0)
809 #define	NGI_CLR_NODE(i)							\
810 	do { _ngi_check(i, _NN_); _NGI_CLR_NODE(i); } while (0)
811 
812 #define NG_FREE_ITEM(item)						\
813 	do {								\
814 		_ngi_check(item, _NN_);					\
815 		ng_free_item((item));					\
816 	} while (0)
817 
818 #define	SAVE_LINE(item)							\
819 	do {								\
820 		(item)->lastline = __LINE__;				\
821 		(item)->lastfile = __FILE__;				\
822 	} while (0)
823 
824 #else	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
825 
826 #define NGI_M(i)	_NGI_M(i)
827 #define NGI_MSG(i)	_NGI_MSG(i)
828 #define NGI_RETADDR(i)	_NGI_RETADDR(i)
829 #define NGI_FN(i)	_NGI_FN(i)
830 #define NGI_FN2(i)	_NGI_FN2(i)
831 #define NGI_ARG1(i)	_NGI_ARG1(i)
832 #define NGI_ARG2(i)	_NGI_ARG2(i)
833 #define	NGI_NODE(i)	_NGI_NODE(i)
834 #define	NGI_HOOK(i)	_NGI_HOOK(i)
835 #define	NGI_SET_HOOK(i,h) _NGI_SET_HOOK(i,h)
836 #define	NGI_CLR_HOOK(i)	  _NGI_CLR_HOOK(i)
837 #define	NGI_SET_NODE(i,n) _NGI_SET_NODE(i,n)
838 #define	NGI_CLR_NODE(i)	  _NGI_CLR_NODE(i)
839 
840 #define	NG_FREE_ITEM(item)	ng_free_item((item))
841 #define	SAVE_LINE(item)		do {} while (0)
842 
843 #endif	/* NETGRAPH_DEBUG */ /*----------------------------------------------*/
844 
845 #define NGI_GET_M(i,m)							\
846 	do {								\
847 		(m) = NGI_M(i);						\
848 		_NGI_M(i) = NULL;					\
849 	} while (0)
850 
851 #define NGI_GET_MSG(i,m)						\
852 	do {								\
853 		(m) = NGI_MSG(i);					\
854 		_NGI_MSG(i) = NULL;					\
855 	} while (0)
856 
857 #define NGI_GET_NODE(i,n)	/* YOU NOW HAVE THE REFERENCE */	\
858 	do {								\
859 		(n) = NGI_NODE(i);					\
860 		_NGI_NODE(i) = NULL;					\
861 	} while (0)
862 
863 #define NGI_GET_HOOK(i,h)						\
864 	do {								\
865 		(h) = NGI_HOOK(i);					\
866 		_NGI_HOOK(i) = NULL;					\
867 	} while (0)
868 
869 #define NGI_SET_WRITER(i)	((i)->el_flags &= ~NGQF_QMODE)
870 #define NGI_SET_READER(i)	((i)->el_flags |= NGQF_QREADER)
871 
872 #define NGI_QUEUED_READER(i)	((i)->el_flags & NGQF_QREADER)
873 #define NGI_QUEUED_WRITER(i)	(((i)->el_flags & NGQF_QMODE) == NGQF_QWRITER)
874 
875 /**********************************************************************
876 * Data macros.  Send, manipulate and free.
877 **********************************************************************/
878 /*
879  * Assuming the data is already ok, just set the new address and send
880  */
881 #define NG_FWD_ITEM_HOOK_FLAGS(error, item, hook, flags)		\
882 	do {								\
883 		(error) =						\
884 		    ng_address_hook(NULL, (item), (hook), NG_NOFLAGS);	\
885 		if (error == 0) {					\
886 			SAVE_LINE(item);				\
887 			(error) = ng_snd_item((item), (flags));		\
888 		}							\
889 		(item) = NULL;						\
890 	} while (0)
891 #define	NG_FWD_ITEM_HOOK(error, item, hook)	\
892 		NG_FWD_ITEM_HOOK_FLAGS(error, item, hook, NG_NOFLAGS)
893 
894 /*
895  * Forward a data packet. Mbuf pointer is updated to new value. We
896  * presume you dealt with the old one when you update it to the new one
897  * (or it maybe the old one). We got a packet and possibly had to modify
898  * the mbuf. You should probably use NGI_GET_M() if you are going to use
899  * this too.
900  */
901 #define NG_FWD_NEW_DATA_FLAGS(error, item, hook, m, flags)		\
902 	do {								\
903 		NGI_M(item) = (m);					\
904 		(m) = NULL;						\
905 		NG_FWD_ITEM_HOOK_FLAGS(error, item, hook, flags);	\
906 	} while (0)
907 #define	NG_FWD_NEW_DATA(error, item, hook, m)	\
908 		NG_FWD_NEW_DATA_FLAGS(error, item, hook, m, NG_NOFLAGS)
909 
910 /* Send a previously unpackaged mbuf. XXX: This should be called
911  * NG_SEND_DATA in future, but this name is kept for compatibility
912  * reasons.
913  */
914 #define NG_SEND_DATA_FLAGS(error, hook, m, flags)			\
915 	do {								\
916 		item_p _item;						\
917 		if ((_item = ng_package_data((m), flags))) {		\
918 			NG_FWD_ITEM_HOOK_FLAGS(error, _item, hook, flags);\
919 		} else {						\
920 			(error) = ENOMEM;				\
921 		}							\
922 		(m) = NULL;						\
923 	} while (0)
924 
925 #define NG_SEND_DATA_ONLY(error, hook, m)	\
926 		NG_SEND_DATA_FLAGS(error, hook, m, NG_NOFLAGS)
927 /* NG_SEND_DATA() compat for meta-data times */
928 #define	NG_SEND_DATA(error, hook, m, x)	\
929 		NG_SEND_DATA_FLAGS(error, hook, m, NG_NOFLAGS)
930 
931 #define NG_FREE_MSG(msg)						\
932 	do {								\
933 		if ((msg)) {						\
934 			free((msg), M_NETGRAPH_MSG);			\
935 			(msg) = NULL;					\
936 		}	 						\
937 	} while (0)
938 
939 #define NG_FREE_M(m)							\
940 	do {								\
941 		if ((m)) {						\
942 			m_freem((m));					\
943 			(m) = NULL;					\
944 		}							\
945 	} while (0)
946 
947 /*****************************************
948 * Message macros
949 *****************************************/
950 
951 #define NG_SEND_MSG_HOOK(error, here, msg, hook, retaddr)		\
952 	do {								\
953 		item_p _item;						\
954 		if ((_item = ng_package_msg(msg, NG_NOFLAGS)) == NULL) {\
955 			(msg) = NULL;					\
956 			(error) = ENOMEM;				\
957 			break;						\
958 		}							\
959 		if (((error) = ng_address_hook((here), (_item),		\
960 					(hook), (retaddr))) == 0) {	\
961 			SAVE_LINE(_item);				\
962 			(error) = ng_snd_item((_item), 0);		\
963 		}							\
964 		(msg) = NULL;						\
965 	} while (0)
966 
967 #define NG_SEND_MSG_PATH(error, here, msg, path, retaddr)		\
968 	do {								\
969 		item_p _item;						\
970 		if ((_item = ng_package_msg(msg, NG_NOFLAGS)) == NULL) {\
971 			(msg) = NULL;					\
972 			(error) = ENOMEM;				\
973 			break;						\
974 		}							\
975 		if (((error) = ng_address_path((here), (_item),		\
976 					(path), (retaddr))) == 0) {	\
977 			SAVE_LINE(_item);				\
978 			(error) = ng_snd_item((_item), 0);		\
979 		}							\
980 		(msg) = NULL;						\
981 	} while (0)
982 
983 #define NG_SEND_MSG_ID(error, here, msg, ID, retaddr)			\
984 	do {								\
985 		item_p _item;						\
986 		if ((_item = ng_package_msg(msg, NG_NOFLAGS)) == NULL) {\
987 			(msg) = NULL;					\
988 			(error) = ENOMEM;				\
989 			break;						\
990 		}							\
991 		if (((error) = ng_address_ID((here), (_item),		\
992 					(ID), (retaddr))) == 0) {	\
993 			SAVE_LINE(_item);				\
994 			(error) = ng_snd_item((_item), 0);		\
995 		}							\
996 		(msg) = NULL;						\
997 	} while (0)
998 
999 /*
1000  * Redirect the message to the next hop using the given hook.
1001  * ng_retarget_msg() frees the item if there is an error
1002  * and returns an error code.  It returns 0 on success.
1003  */
1004 #define NG_FWD_MSG_HOOK(error, here, item, hook, retaddr)		\
1005 	do {								\
1006 		if (((error) = ng_address_hook((here), (item),		\
1007 					(hook), (retaddr))) == 0) {	\
1008 			SAVE_LINE(item);				\
1009 			(error) = ng_snd_item((item), 0);		\
1010 		}							\
1011 		(item) = NULL;						\
1012 	} while (0)
1013 
1014 /*
1015  * Send a queue item back to it's originator with a response message.
1016  * Assume original message was removed and freed separatly.
1017  */
1018 #define NG_RESPOND_MSG(error, here, item, resp)				\
1019 	do {								\
1020 		if (resp) {						\
1021 			ng_ID_t _dest = NGI_RETADDR(item);		\
1022 			NGI_RETADDR(item) = 0;				\
1023 			NGI_MSG(item) = resp;				\
1024 			if ((error = ng_address_ID((here), (item),	\
1025 					_dest, 0)) == 0) {		\
1026 				SAVE_LINE(item);			\
1027 				(error) = ng_snd_item((item), NG_QUEUE);\
1028 			}						\
1029 		} else							\
1030 			NG_FREE_ITEM(item);				\
1031 		(item) = NULL;						\
1032 	} while (0)
1033 
1034 /***********************************************************************
1035  ******** Structures Definitions and Macros for defining a node  *******
1036  ***********************************************************************
1037  *
1038  * Here we define the structures needed to actually define a new node
1039  * type.
1040  */
1041 
1042 /*
1043  * Command list -- each node type specifies the command that it knows
1044  * how to convert between ASCII and binary using an array of these.
1045  * The last element in the array must be a terminator with cookie=0.
1046  */
1047 
1048 struct ng_cmdlist {
1049 	u_int32_t			cookie;		/* command typecookie */
1050 	int				cmd;		/* command number */
1051 	const char			*name;		/* command name */
1052 	const struct ng_parse_type	*mesgType;	/* args if !NGF_RESP */
1053 	const struct ng_parse_type	*respType;	/* args if NGF_RESP */
1054 };
1055 
1056 /*
1057  * Structure of a node type
1058  * If data is sent to the "rcvdata()" entrypoint then the system
1059  * may decide to defer it until later by queing it with the normal netgraph
1060  * input queuing system.  This is decidde by the HK_QUEUE flag being set in
1061  * the flags word of the peer (receiving) hook. The dequeuing mechanism will
1062  * ensure it is not requeued again.
1063  * Note the input queueing system is to allow modules
1064  * to 'release the stack' or to pass data across spl layers.
1065  * The data will be redelivered as soon as the NETISR code runs
1066  * which may be almost immediately.  A node may also do it's own queueing
1067  * for other reasons (e.g. device output queuing).
1068  */
1069 struct ng_type {
1070 	u_int32_t	version; 	/* must equal NG_API_VERSION */
1071 	const char	*name;		/* Unique type name */
1072 	modeventhand_t	mod_event;	/* Module event handler (optional) */
1073 	ng_constructor_t *constructor;	/* Node constructor */
1074 	ng_rcvmsg_t	*rcvmsg;	/* control messages come here */
1075 	ng_close_t	*close;		/* warn about forthcoming shutdown */
1076 	ng_shutdown_t	*shutdown;	/* reset, and free resources */
1077 	ng_newhook_t	*newhook;	/* first notification of new hook */
1078 	ng_findhook_t	*findhook;	/* only if you have lots of hooks */
1079 	ng_connect_t	*connect;	/* final notification of new hook */
1080 	ng_rcvdata_t	*rcvdata;	/* data comes here */
1081 	ng_disconnect_t	*disconnect;	/* notify on disconnect */
1082 
1083 	const struct	ng_cmdlist *cmdlist;	/* commands we can convert */
1084 
1085 	/* R/W data private to the base netgraph code DON'T TOUCH! */
1086 	LIST_ENTRY(ng_type) types;		/* linked list of all types */
1087 	int		    refs;		/* number of instances */
1088 };
1089 
1090 /*
1091  * Use the NETGRAPH_INIT() macro to link a node type into the
1092  * netgraph system. This works for types compiled into the kernel
1093  * as well as KLD modules. The first argument should be the type
1094  * name (eg, echo) and the second a pointer to the type struct.
1095  *
1096  * If a different link time is desired, e.g., a device driver that
1097  * needs to install its netgraph type before probing, use the
1098  * NETGRAPH_INIT_ORDERED() macro instead.  Device drivers probably
1099  * want to use SI_SUB_DRIVERS/SI_ORDER_FIRST.
1100  */
1101 
1102 #define NETGRAPH_INIT_ORDERED(typename, typestructp, sub, order)	\
1103 static moduledata_t ng_##typename##_mod = {				\
1104 	"ng_" #typename,						\
1105 	ng_mod_event,							\
1106 	(typestructp)							\
1107 };									\
1108 DECLARE_MODULE(ng_##typename, ng_##typename##_mod, sub, order);		\
1109 MODULE_DEPEND(ng_##typename, netgraph,	NG_ABI_VERSION,			\
1110 					NG_ABI_VERSION,			\
1111 					NG_ABI_VERSION)
1112 
1113 #define NETGRAPH_INIT(tn, tp)						\
1114 	NETGRAPH_INIT_ORDERED(tn, tp, SI_SUB_PSEUDO, SI_ORDER_MIDDLE)
1115 
1116 /* Special malloc() type for netgraph structs and ctrl messages */
1117 /* Only these two types should be visible to nodes */
1118 MALLOC_DECLARE(M_NETGRAPH);
1119 MALLOC_DECLARE(M_NETGRAPH_MSG);
1120 
1121 /* declare the base of the netgraph sysclt hierarchy */
1122 /* but only if this file cares about sysctls */
1123 #ifdef	SYSCTL_DECL
1124 SYSCTL_DECL(_net_graph);
1125 #endif
1126 
1127 /*
1128  * Methods that the nodes can use.
1129  * Many of these methods should usually NOT be used directly but via
1130  * Macros above.
1131  */
1132 int	ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr);
1133 int	ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr);
1134 int	ng_address_path(node_p here, item_p item, const char *address, ng_ID_t raddr);
1135 int	ng_bypass(hook_p hook1, hook_p hook2);
1136 hook_p	ng_findhook(node_p node, const char *name);
1137 struct	ng_type *ng_findtype(const char *type);
1138 int	ng_make_node_common(struct ng_type *typep, node_p *nodep);
1139 int	ng_name_node(node_p node, const char *name);
1140 node_p	ng_name2noderef(node_p node, const char *name);
1141 int	ng_newtype(struct ng_type *tp);
1142 ng_ID_t ng_node2ID(node_p node);
1143 item_p	ng_package_data(struct mbuf *m, int flags);
1144 item_p	ng_package_msg(struct ng_mesg *msg, int flags);
1145 item_p	ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg);
1146 void	ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr);
1147 int	ng_rmhook_self(hook_p hook);	/* if a node wants to kill a hook */
1148 int	ng_rmnode_self(node_p here);	/* if a node wants to suicide */
1149 int	ng_rmtype(struct ng_type *tp);
1150 int	ng_snd_item(item_p item, int queue);
1151 int 	ng_send_fn(node_p node, hook_p hook, ng_item_fn *fn, void *arg1,
1152 	int arg2);
1153 int 	ng_send_fn1(node_p node, hook_p hook, ng_item_fn *fn, void *arg1,
1154 	int arg2, int flags);
1155 int 	ng_send_fn2(node_p node, hook_p hook, item_p pitem, ng_item_fn2 *fn,
1156 	void *arg1, int arg2, int flags);
1157 int	ng_uncallout(struct callout *c, node_p node);
1158 int	ng_callout(struct callout *c, node_p node, hook_p hook, int ticks,
1159 	    ng_item_fn *fn, void * arg1, int arg2);
1160 #define	ng_callout_init(c)	callout_init(c, 1)
1161 
1162 /* Flags for netgraph functions. */
1163 #define	NG_NOFLAGS	0x00000000	/* no special options */
1164 #define	NG_QUEUE	0x00000001	/* enqueue item, don't dispatch */
1165 #define	NG_WAITOK	0x00000002	/* use M_WAITOK, etc. */
1166 /* XXXGL: NG_PROGRESS unused since ng_base.c rev. 1.136. Should be deleted? */
1167 #define	NG_PROGRESS	0x00000004	/* return EINPROGRESS if queued */
1168 #define	NG_REUSE_ITEM	0x00000008	/* supplied item should be reused */
1169 
1170 /*
1171  * prototypes the user should DEFINITELY not use directly
1172  */
1173 void	ng_free_item(item_p item); /* Use NG_FREE_ITEM instead */
1174 int	ng_mod_event(module_t mod, int what, void *arg);
1175 
1176 /*
1177  * Tag definitions and constants
1178  */
1179 
1180 #define	NG_TAG_PRIO	1
1181 
1182 struct ng_tag_prio {
1183 	struct m_tag	tag;
1184 	char	priority;
1185 	char	discardability;
1186 };
1187 
1188 #define	NG_PRIO_CUTOFF		32
1189 #define	NG_PRIO_LINKSTATE	64
1190 
1191 /* Macros and declarations to keep compatibility with metadata, which
1192  * is obsoleted now. To be deleted.
1193  */
1194 typedef void *meta_p;
1195 #define _NGI_META(i)	NULL
1196 #define NGI_META(i)	NULL
1197 #define NG_FREE_META(meta)
1198 #define NGI_GET_META(i,m)
1199 #define	ng_copy_meta(meta) NULL
1200 
1201 /*
1202  * Mark the current thread when called from the outbound path of the
1203  * network stack, in order to enforce queuing on ng nodes calling into
1204  * the inbound network stack path.
1205  */
1206 #define NG_OUTBOUND_THREAD_REF()					\
1207 	curthread->td_ng_outbound++
1208 #define NG_OUTBOUND_THREAD_UNREF()					\
1209 	do {								\
1210 		curthread->td_ng_outbound--;				\
1211 		KASSERT(curthread->td_ng_outbound >= 0,			\
1212 		    ("%s: negative td_ng_outbound", __func__));		\
1213 	} while (0)
1214 
1215 #endif /* _NETGRAPH_NETGRAPH_H_ */
1216