xref: /dragonfly/sys/netgraph/netgraph.h (revision 984263bc)
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_ 1
45 
46 #include <sys/queue.h>
47 #include <sys/malloc.h>
48 #include <sys/module.h>
49 
50 #ifndef _KERNEL
51 #error "This file should not be included in user level programs"
52 #endif
53 
54 #define NG_ABI_VERSION NG_VERSION
55 
56 /*
57  * Structure of a hook
58  */
59 struct ng_hook {
60 	char   *name;		/* what this node knows this link as */
61 	void   *private;	/* node dependant ID for this hook */
62 	int	flags;		/* info about this hook/link */
63 	int	refs;		/* dont actually free this till 0 */
64 	struct	ng_hook *peer;	/* the other end of this link */
65 	struct	ng_node *node;	/* The node this hook is attached to */
66 	LIST_ENTRY(ng_hook) hooks;	/* linked list of all hooks on node */
67 };
68 typedef struct ng_hook *hook_p;
69 
70 /* Flags for a hook */
71 #define HK_INVALID		0x0001	/* don't trust it! */
72 
73 void ng_unref_hook(hook_p hook); /* don't move this */
74 #define NG_HOOK_REF(hook)	atomic_add_int(&(hook)->refs, 1)
75 #define NG_HOOK_NAME(hook)	((hook)->name)
76 #define NG_HOOK_UNREF(hook)	ng_unref_hook(hook)
77 #define NG_HOOK_SET_PRIVATE(hook, val)	do {(hook)->private = val;} while (0)
78 #define NG_HOOK_SET_RCVMSG(hook, val)	do {(hook)->rcvmsg = val;} while (0)
79 #define NG_HOOK_SET_RCVDATA(hook, val)	do {(hook)->rcvdata = val;} while (0)
80 #define NG_HOOK_PRIVATE(hook)	((hook)->private)
81 #define NG_HOOK_NOT_VALID(hook)	((hook)->flags & HK_INVALID)
82 #define NG_HOOK_IS_VALID(hook)	(!((hook)->flags & HK_INVALID))
83 #define NG_HOOK_NODE(hook)	((hook)->node) /* only rvalue! */
84 #define NG_HOOK_PEER(hook)	((hook)->peer) /* only rvalue! */
85 
86 /* Some shortcuts */
87 #define NG_PEER_NODE(hook)	NG_HOOK_NODE(NG_HOOK_PEER(hook))
88 #define NG_PEER_HOOK_NAME(hook)	NG_HOOK_NAME(NG_HOOK_PEER(hook))
89 #define NG_PEER_NODE_NAME(hook)	NG_NODE_NAME(NG_PEER_NODE(hook))
90 
91 /*
92  * Structure of a node
93  */
94 struct ng_node {
95 	char   *name;		/* optional globally unique name */
96 	struct	ng_type *type;	/* the installed 'type' */
97 	int	flags;		/* see below for bit definitions */
98 	int	sleepers;	/* #procs sleeping on this node */
99 	int	refs;		/* number of references to this node */
100 	int	numhooks;	/* number of hooks */
101 	int	colour;		/* for graph colouring algorithms */
102 	void   *private;	/* node type dependant node ID */
103 	ng_ID_t		ID;	/* Unique per node */
104 	LIST_HEAD(hooks, ng_hook) hooks;	/* linked list of node hooks */
105 	LIST_ENTRY(ng_node)	  nodes;	/* linked list of all nodes */
106 	LIST_ENTRY(ng_node)	  idnodes;	/* ID hash collision list */
107 };
108 typedef struct ng_node *node_p;
109 
110 /* Flags for a node */
111 #define NG_INVALID	0x001	/* free when all sleepers and refs go to 0 */
112 #define NG_BUSY		0x002	/* callers should sleep or wait */
113 #define NG_TOUCHED	0x004	/* to avoid cycles when 'flooding' */
114 #define NGF_TYPE1	0x10000000	/* reserved for type specific storage */
115 #define NGF_TYPE2	0x20000000	/* reserved for type specific storage */
116 #define NGF_TYPE3	0x40000000	/* reserved for type specific storage */
117 #define NGF_TYPE4	0x80000000	/* reserved for type specific storage */
118 
119 void	ng_unref_node(node_p node); /* don't move this */
120 #define NG_NODE_NAME(node)	((node)->name + 0)
121 #define NG_NODE_HAS_NAME(node)	((node)->name[0] + 0)
122 #define NG_NODE_ID(node)	((node)->ID + 0)
123 #define NG_NODE_REF(node)	atomic_add_int(&(node)->refs, 1)
124 #define NG_NODE_UNREF(node)	ng_unref(node)
125 #define NG_NODE_SET_PRIVATE(node, val)	do {(node)->private = val;} while (0)
126 #define NG_NODE_PRIVATE(node)	((node)->private)
127 #define NG_NODE_IS_VALID(node)	(!((node)->flags & NG_INVALID))
128 #define NG_NODE_NOT_VALID(node)	((node)->flags & NG_INVALID)
129 #define NG_NODE_NUMHOOKS(node)	((node)->numhooks + 0) /* rvalue */
130 
131 /*
132  * The structure that holds meta_data about a data packet (e.g. priority)
133  * Nodes might add or subtract options as needed if there is room.
134  * They might reallocate the struct to make more room if they need to.
135  * Meta-data is still experimental.
136  */
137 struct meta_field_header {
138 	u_long	cookie;		/* cookie for the field. Skip fields you don't
139 				 * know about (same cookie as in messgaes) */
140 	u_short type;		/* field ID */
141 	u_short len;		/* total len of this field including extra
142 				 * data */
143 	char	data[0];	/* data starts here */
144 };
145 
146 /* To zero out an option 'in place' set it's cookie to this */
147 #define NGM_INVALID_COOKIE	865455152
148 
149 /* This part of the metadata is always present if the pointer is non NULL */
150 struct ng_meta {
151 	char	priority;	/* -ve is less priority,  0 is default */
152 	char	discardability; /* higher is less valuable.. discard first */
153 	u_short allocated_len;	/* amount malloc'd */
154 	u_short used_len;	/* sum of all fields, options etc. */
155 	u_short flags;		/* see below.. generic flags */
156 	struct meta_field_header options[0];	/* add as (if) needed */
157 };
158 typedef struct ng_meta *meta_p;
159 
160 /* Flags for meta-data */
161 #define NGMF_TEST	0x01	/* discard at the last moment before sending */
162 #define NGMF_TRACE	0x02	/* trace when handing this data to a node */
163 
164 /* node method definitions */
165 typedef	int	ng_constructor_t(node_p *node);
166 typedef	int	ng_rcvmsg_t(node_p node, struct ng_mesg *msg,
167 			const char *retaddr, struct ng_mesg **resp);
168 typedef	int	ng_shutdown_t(node_p node);
169 typedef	int	ng_newhook_t(node_p node, hook_p hook, const char *name);
170 typedef	hook_p	ng_findhook_t(node_p node, const char *name);
171 typedef	int	ng_connect_t(hook_p hook);
172 typedef	int	ng_rcvdata_t(hook_p hook, struct mbuf *m, meta_p meta);
173 typedef	int	ng_disconnect_t(hook_p hook);
174 
175 /*
176  * Command list -- each node type specifies the command that it knows
177  * how to convert between ASCII and binary using an array of these.
178  * The last element in the array must be a terminator with cookie=0.
179  */
180 
181 struct ng_cmdlist {
182 	u_int32_t			cookie;		/* command typecookie */
183 	int				cmd;		/* command number */
184 	const char			*name;		/* command name */
185 	const struct ng_parse_type	*mesgType;	/* args if !NGF_RESP */
186 	const struct ng_parse_type	*respType;	/* args if NGF_RESP */
187 };
188 
189 /*
190  * Structure of a node type
191  */
192 struct ng_type {
193 
194 	u_int32_t	version; 	/* must equal NG_VERSION */
195 	const char	*name;		/* Unique type name */
196 	modeventhand_t	mod_event;	/* Module event handler (optional) */
197 	ng_constructor_t *constructor;	/* Node constructor */
198 	ng_rcvmsg_t	*rcvmsg;	/* control messages come here */
199 	ng_shutdown_t	*shutdown;	/* reset, and free resources */
200 	ng_newhook_t	*newhook;	/* first notification of new hook */
201 	ng_findhook_t	*findhook;	/* only if you have lots of hooks */
202 	ng_connect_t	*connect;	/* final notification of new hook */
203 	ng_rcvdata_t	*rcvdata;	/* date comes here */
204 	ng_rcvdata_t	*rcvdataq;	/* or here if being queued */
205 	ng_disconnect_t	*disconnect;	/* notify on disconnect */
206 
207 	const struct	ng_cmdlist *cmdlist;	/* commands we can convert */
208 
209 	/* R/W data private to the base netgraph code DON'T TOUCH! */
210 	LIST_ENTRY(ng_type) types;		/* linked list of all types */
211 	int		    refs;		/* number of instances */
212 };
213 
214 /* Send data packet with meta-data */
215 #define NG_SEND_DATA(error, hook, m, a)					\
216 	do {								\
217 		(error) = ng_send_data((hook), (m), (a));		\
218 		(m) = NULL;						\
219 		(a) = NULL;						\
220 	} while (0)
221 
222 #define NG_SEND_DATA_ONLY(error, hook, m)				\
223 	do {								\
224 		(error) = ng_send_data((hook), (m), NULL);		\
225 		(m) = NULL;						\
226 	} while (0)
227 
228 /* Send  queued data packet with meta-data */
229 #define NG_SEND_DATAQ(error, hook, m, a)				\
230 	do {								\
231 		(error) = ng_send_dataq((hook), (m), (a));		\
232 		(m) = NULL;						\
233 		(a) = NULL;						\
234 	} while (0)
235 
236 #define NG_RESPOND_MSG(error, here, retaddr, resp, rptr)		\
237 	do {								\
238 		if (rptr) {						\
239 			*rptr = resp;					\
240 		} else if (resp) {					\
241 			if (retaddr) {					\
242 				error = ng_queue_msg(here, resp, retaddr); \
243 			} else {					\
244 				FREE(resp, M_NETGRAPH);			\
245 			}						\
246 		}							\
247 	} while (0)
248 
249 #define NG_FREE_MSG(msg)						\
250 	do {								\
251 		if ((msg)) {						\
252 			FREE((msg), M_NETGRAPH);			\
253 			(msg) = NULL;					\
254 		}	 						\
255 	} while (0)
256 
257 #define NG_FREE_META(a)							\
258 	do {								\
259 		if ((a)) {						\
260 			FREE((a), M_NETGRAPH);				\
261 			(a) = NULL;					\
262 		}							\
263 	} while (0)
264 
265 #define NG_FREE_M(m)							\
266 	do {								\
267 		if ((m)) {						\
268 			m_freem((m));					\
269 			(m) = NULL;					\
270 		}							\
271 	} while (0)
272 
273 /* Free any data packet and/or meta-data */
274 #define NG_FREE_DATA(m, a)						\
275 	do {								\
276 		NG_FREE_M((m));						\
277 		NG_FREE_META((a));					\
278 	} while (0)
279 
280 /*
281  * Use the NETGRAPH_INIT() macro to link a node type into the
282  * netgraph system. This works for types compiled into the kernel
283  * as well as KLD modules. The first argument should be the type
284  * name (eg, echo) and the second a pointer to the type struct.
285  *
286  * If a different link time is desired, e.g., a device driver that
287  * needs to install its netgraph type before probing, use the
288  * NETGRAPH_INIT_ORDERED() macro instead. Deivce drivers probably
289  * want to use SI_SUB_DRIVERS instead of SI_SUB_PSEUDO.
290  */
291 
292 #define NETGRAPH_INIT_ORDERED(typename, typestructp, sub, order)	\
293 static moduledata_t ng_##typename##_mod = {				\
294 	"ng_" #typename,						\
295 	ng_mod_event,							\
296 	(typestructp)							\
297 };									\
298 DECLARE_MODULE(ng_##typename, ng_##typename##_mod, sub, order)
299 
300 #define NETGRAPH_INIT(tn, tp)						\
301 	NETGRAPH_INIT_ORDERED(tn, tp, SI_SUB_PSEUDO, SI_ORDER_ANY)
302 
303 /* Special malloc() type for netgraph structs and ctrl messages */
304 MALLOC_DECLARE(M_NETGRAPH);
305 
306 /* declare the base of the netgraph sysctl hierarchy */
307 /* but only if this file cares about sysctls */
308 #ifdef	SYSCTL_DECL
309 SYSCTL_DECL(_net_graph);
310 #endif
311 
312 int	ng_bypass(hook_p hook1, hook_p hook2);
313 void	ng_cutlinks(node_p node);
314 int	ng_con_nodes(node_p node,
315 	     const char *name, node_p node2, const char *name2);
316 meta_p	ng_copy_meta(meta_p meta);
317 void	ng_destroy_hook(hook_p hook);
318 hook_p	ng_findhook(node_p node, const char *name);
319 node_p	ng_findname(node_p node, const char *name);
320 struct	ng_type *ng_findtype(const char *type);
321 int	ng_make_node(const char *type, node_p *nodepp);
322 int	ng_make_node_common(struct ng_type *typep, node_p *nodep);
323 int	ng_mkpeer(node_p node, const char *name, const char *name2, char *type);
324 int	ng_mod_event(module_t mod, int what, void *arg);
325 int	ng_name_node(node_p node, const char *name);
326 int	ng_newtype(struct ng_type *tp);
327 ng_ID_t ng_node2ID(node_p node);
328 int	ng_path2node(node_p here, const char *path, node_p *dest, char **rtnp);
329 int	ng_path_parse(char *addr, char **node, char **path, char **hook);
330 int	ng_queue_data(hook_p hook, struct mbuf *m, meta_p meta);
331 int	ng_queue_msg(node_p here, struct ng_mesg *msg, const char *address);
332 void	ng_release_node(node_p node);
333 void	ng_rmnode(node_p node);
334 int	ng_send_data(hook_p hook, struct mbuf *m, meta_p meta);
335 int	ng_send_dataq(hook_p hook, struct mbuf *m, meta_p meta);
336 int	ng_send_msg(node_p here, struct ng_mesg *msg,
337 	    const char *address, struct ng_mesg **resp);
338 void	ng_unname(node_p node);
339 void	ng_unref(node_p node);
340 int	ng_wait_node(node_p node, char *msg);
341 
342 #endif /* _NETGRAPH_NETGRAPH_H_ */
343 
344