xref: /dragonfly/sys/netgraph/netgraph.h (revision ef2b2b9d)
1 
2 /*
3  * netgraph.h
4  *
5  * Copyright (c) 1996-1999 Whistle Communications, Inc.
6  * All rights reserved.
7  *
8  * Subject to the following obligations and disclaimer of warranty, use and
9  * redistribution of this software, in source or object code forms, with or
10  * without modifications are expressly permitted by Whistle Communications;
11  * provided, however, that:
12  * 1. Any and all reproductions of the source or object code must include the
13  *    copyright notice above and the following disclaimer of warranties; and
14  * 2. No rights are granted, in any manner or form, to use Whistle
15  *    Communications, Inc. trademarks, including the mark "WHISTLE
16  *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
17  *    such appears in the above copyright notice or in the software.
18  *
19  * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
20  * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
21  * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
22  * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
23  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
24  * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
25  * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
26  * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
27  * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
28  * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
29  * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
30  * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
31  * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
32  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
34  * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
35  * OF SUCH DAMAGE.
36  *
37  * Author: Julian Elischer <julian@freebsd.org>
38  *
39  * $FreeBSD: src/sys/netgraph/netgraph.h,v 1.6.2.7 2002/04/14 23:31:08 julian Exp $
40  * $Whistle: netgraph.h,v 1.29 1999/11/01 07:56:13 julian Exp $
41  */
42 
43 #ifndef _NETGRAPH_NETGRAPH_H_
44 #define _NETGRAPH_NETGRAPH_H_
45 
46 #ifndef _SYS_QUEUE_H_
47 #include <sys/queue.h>
48 #endif
49 #ifndef _SYS_MODULE_H_
50 #include <sys/module.h>
51 #endif
52 #ifndef _SYS_MBUF_H_
53 #include <sys/mbuf.h>
54 #endif
55 #ifndef _NETGRAPH_NG_MESSAGE_H_
56 #include <netgraph/ng_message.h>
57 #endif
58 
59 #ifndef _KERNEL
60 #error "This file should not be included in user level programs"
61 #endif
62 
63 #define NG_ABI_VERSION NG_VERSION
64 
65 /*
66  * Structure of a hook
67  */
68 struct ng_hook {
69 	char   *name;		/* what this node knows this link as */
70 	void   *private;	/* node dependant ID for this hook */
71 	int	flags;		/* info about this hook/link */
72 	int	refs;		/* dont actually free this till 0 */
73 	struct	ng_hook *peer;	/* the other end of this link */
74 	struct	ng_node *node;	/* The node this hook is attached to */
75 	LIST_ENTRY(ng_hook) hooks;	/* linked list of all hooks on node */
76 };
77 typedef struct ng_hook *hook_p;
78 
79 /* Flags for a hook */
80 #define HK_INVALID		0x0001	/* don't trust it! */
81 
82 void ng_unref_hook(hook_p hook); /* don't move this */
83 #define NG_HOOK_REF(hook)	atomic_add_int(&(hook)->refs, 1)
84 #define NG_HOOK_NAME(hook)	((hook)->name)
85 #define NG_HOOK_UNREF(hook)	ng_unref_hook(hook)
86 #define NG_HOOK_SET_PRIVATE(hook, val)	do {(hook)->private = val;} while (0)
87 #define NG_HOOK_SET_RCVMSG(hook, val)	do {(hook)->rcvmsg = val;} while (0)
88 #define NG_HOOK_SET_RCVDATA(hook, val)	do {(hook)->rcvdata = val;} while (0)
89 #define NG_HOOK_PRIVATE(hook)	((hook)->private)
90 #define NG_HOOK_NOT_VALID(hook)	((hook)->flags & HK_INVALID)
91 #define NG_HOOK_IS_VALID(hook)	(!((hook)->flags & HK_INVALID))
92 #define NG_HOOK_NODE(hook)	((hook)->node) /* only rvalue! */
93 #define NG_HOOK_PEER(hook)	((hook)->peer) /* only rvalue! */
94 
95 /* Some shortcuts */
96 #define NG_PEER_NODE(hook)	NG_HOOK_NODE(NG_HOOK_PEER(hook))
97 #define NG_PEER_HOOK_NAME(hook)	NG_HOOK_NAME(NG_HOOK_PEER(hook))
98 #define NG_PEER_NODE_NAME(hook)	NG_NODE_NAME(NG_PEER_NODE(hook))
99 
100 /*
101  * Structure of a node
102  */
103 struct ng_node {
104 	char   *name;		/* optional globally unique name */
105 	struct	ng_type *type;	/* the installed 'type' */
106 	int	flags;		/* see below for bit definitions */
107 	int	sleepers;	/* #procs sleeping on this node */
108 	int	refs;		/* number of references to this node */
109 	int	numhooks;	/* number of hooks */
110 	int	colour;		/* for graph colouring algorithms */
111 	void   *private;	/* node type dependant node ID */
112 	ng_ID_t		ID;	/* Unique per node */
113 	LIST_HEAD(hooks, ng_hook) hooks;	/* linked list of node hooks */
114 	LIST_ENTRY(ng_node)	  nodes;	/* linked list of all nodes */
115 	LIST_ENTRY(ng_node)	  idnodes;	/* ID hash collision list */
116 };
117 typedef struct ng_node *node_p;
118 
119 /* Flags for a node */
120 #define NG_INVALID	0x001	/* free when all sleepers and refs go to 0 */
121 #define NG_BUSY		0x002	/* callers should sleep or wait */
122 #define NG_TOUCHED	0x004	/* to avoid cycles when 'flooding' */
123 #define NGF_TYPE1	0x10000000	/* reserved for type specific storage */
124 #define NGF_TYPE2	0x20000000	/* reserved for type specific storage */
125 #define NGF_TYPE3	0x40000000	/* reserved for type specific storage */
126 #define NGF_TYPE4	0x80000000	/* reserved for type specific storage */
127 
128 void	ng_unref_node(node_p node); /* don't move this */
129 #define NG_NODE_NAME(node)	((node)->name + 0)
130 #define NG_NODE_HAS_NAME(node)	((node)->name[0] + 0)
131 #define NG_NODE_ID(node)	((node)->ID + 0)
132 #define NG_NODE_REF(node)	atomic_add_int(&(node)->refs, 1)
133 #define NG_NODE_UNREF(node)	ng_unref(node)
134 #define NG_NODE_SET_PRIVATE(node, val)	do {(node)->private = val;} while (0)
135 #define NG_NODE_PRIVATE(node)	((node)->private)
136 #define NG_NODE_IS_VALID(node)	(!((node)->flags & NG_INVALID))
137 #define NG_NODE_NOT_VALID(node)	((node)->flags & NG_INVALID)
138 #define NG_NODE_NUMHOOKS(node)	((node)->numhooks + 0) /* rvalue */
139 
140 /*
141  * The structure that holds meta_data about a data packet (e.g. priority)
142  * Nodes might add or subtract options as needed if there is room.
143  * They might reallocate the struct to make more room if they need to.
144  * Meta-data is still experimental.
145  */
146 struct meta_field_header {
147 	u_long	cookie;		/* cookie for the field. Skip fields you don't
148 				 * know about (same cookie as in messgaes) */
149 	u_short type;		/* field ID */
150 	u_short len;		/* total len of this field including extra
151 				 * data */
152 	char	data[0];	/* data starts here */
153 };
154 
155 /* To zero out an option 'in place' set it's cookie to this */
156 #define NGM_INVALID_COOKIE	865455152
157 
158 /* This part of the metadata is always present if the pointer is non NULL */
159 struct ng_meta {
160 	char	priority;	/* -ve is less priority,  0 is default */
161 	char	discardability; /* higher is less valuable.. discard first */
162 	u_short allocated_len;	/* amount malloc'd */
163 	u_short used_len;	/* sum of all fields, options etc. */
164 	u_short flags;		/* see below.. generic flags */
165 	struct meta_field_header options[0];	/* add as (if) needed */
166 };
167 typedef struct ng_meta *meta_p;
168 
169 /* Flags for meta-data */
170 #define NGMF_TEST	0x01	/* discard at the last moment before sending */
171 #define NGMF_TRACE	0x02	/* trace when handing this data to a node */
172 
173 /* node method definitions */
174 typedef	int	ng_constructor_t(node_p *node);
175 typedef	int	ng_rcvmsg_t(node_p node, struct ng_mesg *msg,
176 			const char *retaddr, struct ng_mesg **resp);
177 typedef	int	ng_shutdown_t(node_p node);
178 typedef	int	ng_newhook_t(node_p node, hook_p hook, const char *name);
179 typedef	hook_p	ng_findhook_t(node_p node, const char *name);
180 typedef	int	ng_connect_t(hook_p hook);
181 typedef	int	ng_rcvdata_t(hook_p hook, struct mbuf *m, meta_p meta);
182 typedef	int	ng_disconnect_t(hook_p hook);
183 
184 /*
185  * Command list -- each node type specifies the command that it knows
186  * how to convert between ASCII and binary using an array of these.
187  * The last element in the array must be a terminator with cookie=0.
188  */
189 
190 struct ng_cmdlist {
191 	u_int32_t			cookie;		/* command typecookie */
192 	int				cmd;		/* command number */
193 	const char			*name;		/* command name */
194 	const struct ng_parse_type	*mesgType;	/* args if !NGF_RESP */
195 	const struct ng_parse_type	*respType;	/* args if NGF_RESP */
196 };
197 
198 /*
199  * Structure of a node type
200  */
201 struct ng_type {
202 
203 	u_int32_t	version; 	/* must equal NG_VERSION */
204 	const char	*name;		/* Unique type name */
205 	modeventhand_t	mod_event;	/* Module event handler (optional) */
206 	ng_constructor_t *constructor;	/* Node constructor */
207 	ng_rcvmsg_t	*rcvmsg;	/* control messages come here */
208 	ng_shutdown_t	*shutdown;	/* reset, and free resources */
209 	ng_newhook_t	*newhook;	/* first notification of new hook */
210 	ng_findhook_t	*findhook;	/* only if you have lots of hooks */
211 	ng_connect_t	*connect;	/* final notification of new hook */
212 	ng_rcvdata_t	*rcvdata;	/* date comes here */
213 	ng_rcvdata_t	*rcvdataq;	/* or here if being queued */
214 	ng_disconnect_t	*disconnect;	/* notify on disconnect */
215 
216 	const struct	ng_cmdlist *cmdlist;	/* commands we can convert */
217 
218 	/* R/W data private to the base netgraph code DON'T TOUCH! */
219 	LIST_ENTRY(ng_type) types;		/* linked list of all types */
220 	int		    refs;		/* number of instances */
221 };
222 
223 /* Send data packet with meta-data */
224 #define NG_SEND_DATA(error, hook, m, a)					\
225 	do {								\
226 		(error) = ng_send_data((hook), (m), (a));		\
227 		(m) = NULL;						\
228 		(a) = NULL;						\
229 	} while (0)
230 
231 #define NG_SEND_DATA_ONLY(error, hook, m)				\
232 	do {								\
233 		(error) = ng_send_data((hook), (m), NULL);		\
234 		(m) = NULL;						\
235 	} while (0)
236 
237 /* Send  queued data packet with meta-data */
238 #define NG_SEND_DATAQ(error, hook, m, a)				\
239 	do {								\
240 		(error) = ng_send_dataq((hook), (m), (a));		\
241 		(m) = NULL;						\
242 		(a) = NULL;						\
243 	} while (0)
244 
245 #define NG_RESPOND_MSG(error, here, retaddr, resp, rptr)		\
246 	do {								\
247 		if (rptr) {						\
248 			*rptr = resp;					\
249 		} else if (resp) {					\
250 			if (retaddr) {					\
251 				error = ng_queue_msg(here, resp, retaddr); \
252 			} else {					\
253 				kfree(resp, M_NETGRAPH);		\
254 			}						\
255 		}							\
256 	} while (0)
257 
258 #define NG_FREE_MSG(msg)						\
259 	do {								\
260 		if ((msg)) {						\
261 			kfree((msg), M_NETGRAPH);			\
262 			(msg) = NULL;					\
263 		}	 						\
264 	} while (0)
265 
266 #define NG_FREE_META(a)							\
267 	do {								\
268 		if ((a)) {						\
269 			kfree((a), M_NETGRAPH);				\
270 			(a) = NULL;					\
271 		}							\
272 	} while (0)
273 
274 #define NG_FREE_M(m)							\
275 	do {								\
276 		if ((m)) {						\
277 			m_freem((m));					\
278 			(m) = NULL;					\
279 		}							\
280 	} while (0)
281 
282 /* Free any data packet and/or meta-data */
283 #define NG_FREE_DATA(m, a)						\
284 	do {								\
285 		NG_FREE_M((m));						\
286 		NG_FREE_META((a));					\
287 	} while (0)
288 
289 /*
290  * Use the NETGRAPH_INIT() macro to link a node type into the
291  * netgraph system. This works for types compiled into the kernel
292  * as well as KLD modules. The first argument should be the type
293  * name (eg, echo) and the second a pointer to the type struct.
294  *
295  * If a different link time is desired, e.g., a device driver that
296  * needs to install its netgraph type before probing, use the
297  * NETGRAPH_INIT_ORDERED() macro instead. Deivce drivers probably
298  * want to use SI_SUB_DRIVERS instead of SI_SUB_PSEUDO.
299  */
300 
301 #define NETGRAPH_INIT_ORDERED(typename, typestructp, sub, order)	\
302 static moduledata_t ng_##typename##_mod = {				\
303 	"ng_" #typename,						\
304 	ng_mod_event,							\
305 	(typestructp)							\
306 };									\
307 DECLARE_MODULE(ng_##typename, ng_##typename##_mod, sub, order);		\
308 MODULE_VERSION(ng_##typename, NG_ABI_VERSION);				\
309 MODULE_DEPEND(ng_##typename, netgraph,	NG_ABI_VERSION,			\
310 					NG_ABI_VERSION,			\
311 					NG_ABI_VERSION)
312 #define NETGRAPH_INIT(tn, tp)						\
313 	NETGRAPH_INIT_ORDERED(tn, tp, SI_SUB_PSEUDO, SI_ORDER_ANY)
314 
315 /* Special malloc() type for netgraph structs and ctrl messages */
316 #ifdef MALLOC_DECLARE
317 MALLOC_DECLARE(M_NETGRAPH);
318 #endif
319 
320 /* declare the base of the netgraph sysctl hierarchy */
321 /* but only if this file cares about sysctls */
322 #ifdef	SYSCTL_DECL
323 SYSCTL_DECL(_net_graph);
324 #endif
325 
326 int	ng_bypass(hook_p hook1, hook_p hook2);
327 void	ng_cutlinks(node_p node);
328 int	ng_con_nodes(node_p node,
329 	     const char *name, node_p node2, const char *name2);
330 meta_p	ng_copy_meta(meta_p meta);
331 void	ng_destroy_hook(hook_p hook);
332 hook_p	ng_findhook(node_p node, const char *name);
333 node_p	ng_findname(node_p node, const char *name);
334 struct	ng_type *ng_findtype(const char *type);
335 int	ng_make_node(const char *type, node_p *nodepp);
336 int	ng_make_node_common(struct ng_type *typep, node_p *nodep);
337 int	ng_mkpeer(node_p node, const char *name, const char *name2, char *type);
338 int	ng_mod_event(module_t mod, int what, void *arg);
339 int	ng_name_node(node_p node, const char *name);
340 int	ng_newtype(struct ng_type *tp);
341 ng_ID_t ng_node2ID(node_p node);
342 int	ng_path2node(node_p here, const char *path, node_p *dest, char **rtnp);
343 int	ng_path_parse(char *addr, char **node, char **path, char **hook);
344 int	ng_queue_data(hook_p hook, struct mbuf *m, meta_p meta);
345 int	ng_queue_msg(node_p here, struct ng_mesg *msg, const char *address);
346 void	ng_release_node(node_p node);
347 void	ng_rmnode(node_p node);
348 int	ng_send_data(hook_p hook, struct mbuf *m, meta_p meta);
349 int	ng_send_dataq(hook_p hook, struct mbuf *m, meta_p meta);
350 int	ng_send_msg(node_p here, struct ng_mesg *msg,
351 	    const char *address, struct ng_mesg **resp);
352 void	ng_unname(node_p node);
353 void	ng_unref(node_p node);
354 int	ng_wait_node(node_p node, char *msg);
355 
356 #endif	/* _NETGRAPH_NETGRAPH_H_ */
357