xref: /dragonfly/sys/netgraph7/ng_gif_demux.c (revision 6e278935)
1 /*
2  * ng_gif_demux.c
3  */
4 
5 /*-
6  * Copyright 2001 The Aerospace Corporation.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions, and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions, and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. The name of The Aerospace Corporation may not be used to endorse or
18  *    promote products derived from this software.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AEROSPACE CORPORATION ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AEROSPACE CORPORATION BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  *
32  *
33  * Copyright (c) 1996-1999 Whistle Communications, Inc.
34  * All rights reserved.
35  *
36  * Subject to the following obligations and disclaimer of warranty, use and
37  * redistribution of this software, in source or object code forms, with or
38  * without modifications are expressly permitted by Whistle Communications;
39  * provided, however, that:
40  * 1. Any and all reproductions of the source or object code must include the
41  *    copyright notice above and the following disclaimer of warranties; and
42  * 2. No rights are granted, in any manner or form, to use Whistle
43  *    Communications, Inc. trademarks, including the mark "WHISTLE
44  *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
45  *    such appears in the above copyright notice or in the software.
46  *
47  * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
48  * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
49  * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
50  * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
51  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
52  * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
53  * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
54  * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
55  * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
56  * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
57  * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
58  * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
59  * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
60  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
61  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
62  * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
63  * OF SUCH DAMAGE.
64  *
65  * $FreeBSD: src/sys/netgraph/ng_gif_demux.c,v 1.10 2005/01/07 01:45:39 imp Exp $
66  */
67 
68 /*
69  * ng_gif_demux(4) netgraph node type
70  *
71  * Packets received on the "gif" hook have their type header removed
72  * and are passed to the appropriate hook protocol hook.  Packets
73  * recieved on a protocol hook have a type header added back and are
74  * passed out the gif hook. The currently supported protocol hooks are:
75  */
76 
77 #include <sys/param.h>
78 #include <sys/systm.h>
79 #include <sys/kernel.h>
80 #include <sys/malloc.h>
81 #include <sys/ctype.h>
82 #include <sys/mbuf.h>
83 #include <sys/errno.h>
84 #include <sys/socket.h>
85 
86 #include "ng_message.h"
87 #include "netgraph.h"
88 #include "ng_parse.h"
89 #include "ng_gif_demux.h"
90 
91 #ifdef NG_SEPARATE_MALLOC
92 MALLOC_DEFINE(M_NETGRAPH_GIF_DEMUX, "netgraph_gif_demux",
93     "netgraph gif demux node");
94 #else
95 #define M_NETGRAPH_GIF_DEMUX M_NETGRAPH
96 #endif
97 
98 /* This struct describes one address family */
99 struct iffam {
100 	sa_family_t	family;		/* Address family */
101 	const char	*hookname;	/* Name for hook */
102 };
103 typedef const struct iffam *iffam_p;
104 
105 /* List of address families supported by our interface */
106 const static struct iffam gFamilies[] = {
107 	{ AF_INET,	NG_GIF_DEMUX_HOOK_INET	},
108 	{ AF_INET6,	NG_GIF_DEMUX_HOOK_INET6	},
109 	{ AF_IPX,	NG_GIF_DEMUX_HOOK_IPX	},
110 	{ AF_ATM,	NG_GIF_DEMUX_HOOK_ATM	},
111 	{ AF_NATM,	NG_GIF_DEMUX_HOOK_NATM	},
112 };
113 #define NUM_FAMILIES		NELEM(gFamilies)
114 
115 /* Per-node private data */
116 struct ng_gif_demux_private {
117 	node_p	node;			/* Our netgraph node */
118 	hook_p	gif;			/* The gif hook */
119 	hook_p	hooks[NUM_FAMILIES];	/* The protocol hooks */
120 };
121 typedef struct ng_gif_demux_private *priv_p;
122 
123 /* Netgraph node methods */
124 static ng_constructor_t	ng_gif_demux_constructor;
125 static ng_rcvmsg_t	ng_gif_demux_rcvmsg;
126 static ng_shutdown_t	ng_gif_demux_shutdown;
127 static ng_newhook_t	ng_gif_demux_newhook;
128 static ng_rcvdata_t	ng_gif_demux_rcvdata;
129 static ng_disconnect_t	ng_gif_demux_disconnect;
130 
131 /* Helper stuff */
132 static iffam_p	get_iffam_from_af(sa_family_t family);
133 static iffam_p	get_iffam_from_hook(priv_p priv, hook_p hook);
134 static iffam_p	get_iffam_from_name(const char *name);
135 static hook_p	*get_hook_from_iffam(priv_p priv, iffam_p iffam);
136 
137 /******************************************************************
138 		    NETGRAPH PARSE TYPES
139 ******************************************************************/
140 
141 /* List of commands and how to convert arguments to/from ASCII */
142 static const struct ng_cmdlist ng_gif_demux_cmdlist[] = {
143 	{ 0 }
144 };
145 
146 /* Node type descriptor */
147 static struct ng_type ng_gif_demux_typestruct = {
148 	.version =	NG_ABI_VERSION,
149 	.name =		NG_GIF_DEMUX_NODE_TYPE,
150 	.constructor =	ng_gif_demux_constructor,
151 	.rcvmsg =	ng_gif_demux_rcvmsg,
152 	.shutdown =	ng_gif_demux_shutdown,
153 	.newhook =	ng_gif_demux_newhook,
154 	.rcvdata =	ng_gif_demux_rcvdata,
155 	.disconnect =	ng_gif_demux_disconnect,
156 	.cmdlist =	ng_gif_demux_cmdlist,
157 };
158 NETGRAPH_INIT(gif_demux, &ng_gif_demux_typestruct);
159 
160 /************************************************************************
161 		    HELPER STUFF
162  ************************************************************************/
163 
164 /*
165  * Get the family descriptor from the family ID
166  */
167 static __inline iffam_p
168 get_iffam_from_af(sa_family_t family)
169 {
170 	iffam_p iffam;
171 	int k;
172 
173 	for (k = 0; k < NUM_FAMILIES; k++) {
174 		iffam = &gFamilies[k];
175 		if (iffam->family == family)
176 			return (iffam);
177 	}
178 	return (NULL);
179 }
180 
181 /*
182  * Get the family descriptor from the hook
183  */
184 static __inline iffam_p
185 get_iffam_from_hook(priv_p priv, hook_p hook)
186 {
187 	int k;
188 
189 	for (k = 0; k < NUM_FAMILIES; k++)
190 		if (priv->hooks[k] == hook)
191 			return (&gFamilies[k]);
192 	return (NULL);
193 }
194 
195 /*
196  * Get the hook from the iffam descriptor
197  */
198 
199 static __inline hook_p *
200 get_hook_from_iffam(priv_p priv, iffam_p iffam)
201 {
202 	return (&priv->hooks[iffam - gFamilies]);
203 }
204 
205 /*
206  * Get the iffam descriptor from the name
207  */
208 static __inline iffam_p
209 get_iffam_from_name(const char *name)
210 {
211 	iffam_p iffam;
212 	int k;
213 
214 	for (k = 0; k < NUM_FAMILIES; k++) {
215 		iffam = &gFamilies[k];
216 		if (!strcmp(iffam->hookname, name))
217 			return (iffam);
218 	}
219 	return (NULL);
220 }
221 
222 /******************************************************************
223 		    NETGRAPH NODE METHODS
224 ******************************************************************/
225 
226 /*
227  * Node constructor
228  */
229 static int
230 ng_gif_demux_constructor(node_p node)
231 {
232 	priv_p priv;
233 
234 	/* Allocate and initialize private info */
235 	MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH_GIF_DEMUX,
236 	    M_WAITOK | M_NULLOK | M_ZERO);
237 	if (priv == NULL)
238 		return (ENOMEM);
239 	priv->node = node;
240 
241 	NG_NODE_SET_PRIVATE(node, priv);
242 
243 	/* Done */
244 	return (0);
245 }
246 
247 /*
248  * Method for attaching a new hook
249  */
250 static	int
251 ng_gif_demux_newhook(node_p node, hook_p hook, const char *name)
252 {
253 	const priv_p priv = NG_NODE_PRIVATE(node);
254 	iffam_p iffam;
255 	hook_p *hookptr;
256 
257 	if (strcmp(NG_GIF_DEMUX_HOOK_GIF, name) == 0)
258 		hookptr = &priv->gif;
259 	else {
260 		iffam = get_iffam_from_name(name);
261 		if (iffam == NULL)
262 			return (EPFNOSUPPORT);
263 		hookptr = get_hook_from_iffam(NG_NODE_PRIVATE(node), iffam);
264 	}
265 	if (*hookptr != NULL)
266 		return (EISCONN);
267 	*hookptr = hook;
268 	return (0);
269 }
270 
271 /*
272  * Receive a control message
273  */
274 static int
275 ng_gif_demux_rcvmsg(node_p node, item_p item, hook_p lasthook)
276 {
277 	struct ng_mesg *resp = NULL;
278 	int error = 0;
279 	struct ng_mesg *msg;
280 
281 	NGI_GET_MSG(item, msg);
282 	switch (msg->header.typecookie) {
283 	case NGM_GIF_DEMUX_COOKIE:
284 		switch (msg->header.cmd) {
285 		/* XXX: Add commands here. */
286 		default:
287 			error = EINVAL;
288 			break;
289 		}
290 		break;
291 	default:
292 		error = EINVAL;
293 		break;
294 	}
295 
296 	/* Done */
297 	NG_RESPOND_MSG(error, node, item, resp);
298 	NG_FREE_MSG(msg);
299 	return (error);
300 }
301 
302 /*
303  * Receive data on a hook
304  */
305 static int
306 ng_gif_demux_rcvdata(hook_p hook, item_p item)
307 {
308 	const node_p node = NG_HOOK_NODE(hook);
309 	const priv_p priv = NG_NODE_PRIVATE(node);
310 	iffam_p iffam;
311 	hook_p outhook;
312 	int error = 0;
313 	struct mbuf *m;
314 
315 	/* Pull the mbuf out of the item for processing. */
316 	NGI_GET_M(item, m);
317 
318 	if (hook == priv->gif) {
319 		/*
320 		 * Pull off the address family header and find the
321 		 * output hook.
322 		 */
323 		if (m->m_pkthdr.len < sizeof(sa_family_t)) {
324 			NG_FREE_M(m);
325 			NG_FREE_ITEM(item);
326 			return (EINVAL);
327 		}
328 		if (m->m_len < sizeof(sa_family_t)
329 		    && (m = m_pullup(m, sizeof(sa_family_t))) == NULL) {
330 			NG_FREE_ITEM(item);
331 			return (ENOBUFS);
332 		}
333 		iffam = get_iffam_from_af(*mtod(m, sa_family_t *));
334 		if (iffam == NULL) {
335 			NG_FREE_M(m);
336 			NG_FREE_ITEM(item);
337 			return (EINVAL);
338 		}
339 		outhook = *get_hook_from_iffam(priv, iffam);
340 		m_adj(m, sizeof(sa_family_t));
341 	} else {
342 		/*
343 		 * Add address family header and set the output hook.
344 		 */
345 		iffam = get_iffam_from_hook(priv, hook);
346 		M_PREPEND(m, sizeof (iffam->family), MB_DONTWAIT);
347 		if (m == NULL) {
348 			NG_FREE_M(m);
349 			NG_FREE_ITEM(item);
350 			return (ENOBUFS);
351 		}
352 		bcopy(&iffam->family, mtod(m, sa_family_t *),
353 		    sizeof(iffam->family));
354 		outhook = priv->gif;
355 	}
356 
357 	/* Stuff the mbuf back in. */
358 	NGI_M(item) = m;
359 
360 	/* Deliver packet */
361 	NG_FWD_ITEM_HOOK(error, item, outhook);
362 	return (error);
363 }
364 
365 /*
366  * Shutdown node
367  */
368 static int
369 ng_gif_demux_shutdown(node_p node)
370 {
371 	const priv_p priv = NG_NODE_PRIVATE(node);
372 
373 	FREE(priv, M_NETGRAPH_GIF_DEMUX);
374 	NG_NODE_SET_PRIVATE(node, NULL);
375 	NG_NODE_UNREF(node);
376 	return (0);
377 }
378 
379 /*
380  * Hook disconnection.
381  */
382 static int
383 ng_gif_demux_disconnect(hook_p hook)
384 {
385 	const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
386 	iffam_p iffam;
387 
388 	if (hook == priv->gif)
389 		priv->gif = NULL;
390 	else {
391 		iffam = get_iffam_from_hook(priv, hook);
392 		if (iffam == NULL)
393 			panic(__func__);
394 		*get_hook_from_iffam(priv, iffam) = NULL;
395 	}
396 
397 	return (0);
398 }
399