xref: /dragonfly/sys/netgraph/netgraph.h (revision 805c8e8e4093ceca2e27510ad3a66d4de8060a55)
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