xref: /freebsd/sys/netgraph/ng_split.c (revision 5521ff5a4d1929056e7ffc982fac3341ca54df7c)
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  * 	$FreeBSD$
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 */
48 static ng_constructor_t ng_split_constructor;
49 static ng_rcvmsg_t ng_split_rcvmsg;
50 static ng_shutdown_t ng_split_rmnode;
51 static ng_newhook_t ng_split_newhook;
52 static ng_rcvdata_t ng_split_rcvdata;
53 static ng_connect_t ng_split_connect;
54 static ng_disconnect_t ng_split_disconnect;
55 
56 /* Node type descriptor */
57 static 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 };
71 NETGRAPH_INIT(ng_split, &typestruct);
72 
73 /* Node private data */
74 struct ng_split_private {
75         hook_p outhook;
76         hook_p inhook;
77         hook_p mixed;
78 	node_p	node;			/* Our netgraph node */
79 };
80 typedef struct ng_split_private *priv_p;
81 
82 /************************************************************************
83 			NETGRAPH NODE STUFF
84  ************************************************************************/
85 
86 /*
87  * Constructor for a node
88  */
89 static int
90 ng_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  */
111 static int
112 ng_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  */
145 static int
146 ng_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  */
155 static int
156 ng_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 
187 static int
188 ng_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  */
204 static int
205 ng_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  */
214 static int
215 ng_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