xref: /freebsd/sys/netgraph/ng_split.c (revision a0409676120c1e558d0ade943019934e0f15118d)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 1999-2000, Vitaly V Belekhov
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice unmodified, this list of conditions, and the following
12  *    disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * $FreeBSD$
30  *
31  */
32 
33 #include <sys/param.h>
34 #include <sys/systm.h>
35 #include <sys/errno.h>
36 #include <sys/kernel.h>
37 #include <sys/malloc.h>
38 #include <sys/mbuf.h>
39 #include <sys/errno.h>
40 #include <sys/sockio.h>
41 #include <sys/socket.h>
42 #include <sys/syslog.h>
43 
44 #include <netgraph/ng_message.h>
45 #include <netgraph/netgraph.h>
46 #include <netgraph/ng_split.h>
47 
48 /* Netgraph methods */
49 static ng_constructor_t ng_split_constructor;
50 static ng_shutdown_t ng_split_shutdown;
51 static ng_newhook_t ng_split_newhook;
52 static ng_rcvdata_t ng_split_rcvdata;
53 static ng_disconnect_t ng_split_disconnect;
54 
55 /* Node type descriptor */
56 static struct ng_type typestruct = {
57 	.version =	NG_ABI_VERSION,
58 	.name =		NG_SPLIT_NODE_TYPE,
59 	.constructor =	ng_split_constructor,
60 	.shutdown =	ng_split_shutdown,
61 	.newhook =	ng_split_newhook,
62 	.rcvdata =	ng_split_rcvdata,
63 	.disconnect =	ng_split_disconnect,
64 };
65 NETGRAPH_INIT(ng_split, &typestruct);
66 
67 /* Node private data */
68 struct ng_split_private {
69 	hook_p out;
70 	hook_p in;
71 	hook_p mixed;
72 	node_p	node;			/* Our netgraph node */
73 };
74 typedef struct ng_split_private *priv_p;
75 
76 /************************************************************************
77 			NETGRAPH NODE STUFF
78  ************************************************************************/
79 
80 /*
81  * Constructor for a node
82  */
83 static int
84 ng_split_constructor(node_p node)
85 {
86 	priv_p		priv;
87 
88 	/* Allocate node */
89 	priv = malloc(sizeof(*priv), M_NETGRAPH, M_ZERO | M_WAITOK);
90 
91 	/* Link together node and private info */
92 	NG_NODE_SET_PRIVATE(node, priv);
93 	priv->node = node;
94 
95 	/* Done */
96 	return (0);
97 }
98 
99 /*
100  * Give our ok for a hook to be added
101  */
102 static int
103 ng_split_newhook(node_p node, hook_p hook, const char *name)
104 {
105 	priv_p		priv = NG_NODE_PRIVATE(node);
106 	hook_p		*localhook;
107 
108 	if (strcmp(name, NG_SPLIT_HOOK_MIXED) == 0) {
109 		localhook = &priv->mixed;
110 	} else if (strcmp(name, NG_SPLIT_HOOK_IN) == 0) {
111 		localhook = &priv->in;
112 	} else if (strcmp(name, NG_SPLIT_HOOK_OUT) == 0) {
113 		localhook = &priv->out;
114 	} else
115 		return (EINVAL);
116 
117 	if (*localhook != NULL)
118 		return (EISCONN);
119 	*localhook = hook;
120 	NG_HOOK_SET_PRIVATE(hook, localhook);
121 
122 	return (0);
123 }
124 
125 /*
126  * Recive data from a hook.
127  */
128 static int
129 ng_split_rcvdata(hook_p hook, item_p item)
130 {
131 	const priv_p	priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
132 	int		error = 0;
133 
134 	if (hook == priv->out) {
135 		printf("ng_split: got packet from out hook!\n");
136 		NG_FREE_ITEM(item);
137 		error = EINVAL;
138 	} else if ((hook == priv->in) && (priv->mixed != NULL)) {
139 		NG_FWD_ITEM_HOOK(error, item, priv->mixed);
140 	} else if ((hook == priv->mixed) && (priv->out != NULL)) {
141 		NG_FWD_ITEM_HOOK(error, item, priv->out);
142 	}
143 
144 	if (item)
145 		NG_FREE_ITEM(item);
146 
147 	return (error);
148 }
149 
150 static int
151 ng_split_shutdown(node_p node)
152 {
153 	const priv_p	priv = NG_NODE_PRIVATE(node);
154 
155 	NG_NODE_SET_PRIVATE(node, NULL);
156 	NG_NODE_UNREF(node);
157 	free(priv, M_NETGRAPH);
158 
159 	return (0);
160 }
161 
162 /*
163  * Hook disconnection
164  */
165 static int
166 ng_split_disconnect(hook_p hook)
167 {
168 	hook_p		*localhook = NG_HOOK_PRIVATE(hook);
169 
170 	KASSERT(localhook != NULL, ("%s: null info", __func__));
171 	*localhook = NULL;
172 	if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
173 	    && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))) {
174 		ng_rmnode_self(NG_HOOK_NODE(hook));
175 	}
176 
177 	return (0);
178 }
179