ng_split.c revision 72909
1/*-
2 *
3 * Copyright (c) 1999-2000, Vitaly V Belekhov
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice unmodified, this list of conditions, and the following
11 *    disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 * 	$FreeBSD: head/sys/netgraph/ng_split.c 72909 2001-02-22 17:14:36Z julian $
29 *
30 */
31
32#include <sys/param.h>
33#include <sys/systm.h>
34#include <sys/errno.h>
35#include <sys/kernel.h>
36#include <sys/malloc.h>
37#include <sys/mbuf.h>
38#include <sys/errno.h>
39#include <sys/sockio.h>
40#include <sys/socket.h>
41#include <sys/syslog.h>
42
43#include <netgraph/ng_message.h>
44#include <netgraph/netgraph.h>
45#include <netgraph/ng_split.h>
46
47/* Netgraph methods */
48static ng_constructor_t ng_split_constructor;
49static ng_rcvmsg_t ng_split_rcvmsg;
50static ng_shutdown_t ng_split_rmnode;
51static ng_newhook_t ng_split_newhook;
52static ng_rcvdata_t ng_split_rcvdata;
53static ng_connect_t ng_split_connect;
54static ng_disconnect_t ng_split_disconnect;
55
56/* Node type descriptor */
57static struct ng_type typestruct = {
58	NG_ABI_VERSION,
59	NG_SPLIT_NODE_TYPE,
60	NULL,
61	ng_split_constructor,
62	ng_split_rcvmsg,
63	ng_split_rmnode,
64	ng_split_newhook,
65	NULL,
66	ng_split_connect,
67	ng_split_rcvdata,
68	ng_split_disconnect,
69	NULL
70};
71NETGRAPH_INIT(ng_split, &typestruct);
72
73/* Node private data */
74struct ng_split_private {
75        hook_p outhook;
76        hook_p inhook;
77        hook_p mixed;
78	node_p	node;			/* Our netgraph node */
79};
80typedef struct ng_split_private *priv_p;
81
82/************************************************************************
83			NETGRAPH NODE STUFF
84 ************************************************************************/
85
86/*
87 * Constructor for a node
88 */
89static int
90ng_split_constructor(node_p node)
91{
92	priv_p          priv;
93
94	/* Allocate node */
95	MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_ZERO | M_NOWAIT);
96	if (priv == NULL)
97		return (ENOMEM);
98	bzero(priv, sizeof(*priv));
99
100	/* Link together node and private info */
101	NG_NODE_SET_PRIVATE(node, priv);
102	priv->node = node;
103
104	/* Done */
105	return (0);
106}
107
108/*
109 * Give our ok for a hook to be added
110 */
111static int
112ng_split_newhook(node_p node, hook_p hook, const char *name)
113{
114	priv_p          priv = NG_NODE_PRIVATE(node);
115
116	if (strcmp(name, NG_SPLIT_HOOK_MIXED)) {
117		if (strcmp(name, NG_SPLIT_HOOK_INHOOK)) {
118			if (strcmp(name, NG_SPLIT_HOOK_OUTHOOK))
119				return (EPFNOSUPPORT);
120			else {
121				if (priv->outhook != NULL)
122					return (EISCONN);
123				priv->outhook = hook;
124				NG_HOOK_SET_PRIVATE(hook, &(priv->outhook));
125			}
126		} else {
127			if (priv->inhook != NULL)
128				return (EISCONN);
129			priv->inhook = hook;
130			NG_HOOK_SET_PRIVATE(hook, &(priv->inhook));
131		}
132	} else {
133		if (priv->mixed != NULL)
134			return (EISCONN);
135		priv->mixed = hook;
136		NG_HOOK_SET_PRIVATE(hook, &(priv->mixed));
137	}
138
139	return (0);
140}
141
142/*
143 * Receive a control message
144 */
145static int
146ng_split_rcvmsg(node_p node, item_p item, hook_p lasthook)
147{
148	NG_FREE_ITEM(item);
149	return (EINVAL);
150}
151
152/*
153 * Recive data from a hook.
154 */
155static int
156ng_split_rcvdata(hook_p hook, item_p item)
157{
158	meta_p          meta;
159	const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
160	int             error = 0;
161
162	if (hook == priv->outhook) {
163		printf("ng_split: got packet from outhook!\n");
164		NG_FREE_ITEM(item);
165		return (EINVAL);
166	}
167#if 0 /* should never happen */
168	if (NGI_M(item) == NULL) {
169		printf("ng_split: mbuf is null.\n");
170		NG_FREE_ITEM(item);
171		return (EINVAL);
172	}
173#endif
174	/*
175	 * XXX Really here we should just remove metadata we understand.
176	 */
177	NGI_GET_META(item, meta);
178	NG_FREE_META(meta);
179	if ((hook == priv->inhook) && (priv->mixed)) {
180		NG_FWD_ITEM_HOOK(error, item, priv->mixed);
181	} else if ((hook == priv->mixed) && (priv->outhook)) {
182		NG_FWD_ITEM_HOOK(error, item, priv->outhook);
183	}
184	return (error);
185}
186
187static int
188ng_split_rmnode(node_p node)
189{
190	const priv_p priv = NG_NODE_PRIVATE(node);
191
192	NG_NODE_SET_PRIVATE(node, NULL);
193	NG_NODE_UNREF(node);
194	FREE(priv, M_NETGRAPH);
195
196	return (0);
197}
198
199
200/*
201 * This is called once we've already connected a new hook to the other node.
202 * It gives us a chance to balk at the last minute.
203 */
204static int
205ng_split_connect(hook_p hook)
206{
207	/* be really amiable and just say "YUP that's OK by me! " */
208	return (0);
209}
210
211/*
212 * Hook disconnection
213 */
214static int
215ng_split_disconnect(hook_p hook)
216{
217	if (NG_HOOK_PRIVATE(hook)) {
218		*((hook_p *)NG_HOOK_PRIVATE(hook)) = (hook_p)0;
219	}
220
221	if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
222	&& (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))) {
223			ng_rmnode_self(NG_HOOK_NODE(hook));
224	}
225
226	return (0);
227}
228