1/*
2 * ng_gif_demux.c
3 */
4
5/*-
6 * SPDX-License-Identifier: BSD-3-Clause AND BSD-2-Clause
7 *
8 * Copyright 2001 The Aerospace Corporation.  All rights reserved.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 *
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions, and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions, and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 * 3. The name of The Aerospace Corporation may not be used to endorse or
20 *    promote products derived from this software.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE AEROSPACE CORPORATION ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AEROSPACE CORPORATION BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 *
34 *
35 * Copyright (c) 1996-1999 Whistle Communications, Inc.
36 * All rights reserved.
37 *
38 * Subject to the following obligations and disclaimer of warranty, use and
39 * redistribution of this software, in source or object code forms, with or
40 * without modifications are expressly permitted by Whistle Communications;
41 * provided, however, that:
42 * 1. Any and all reproductions of the source or object code must include the
43 *    copyright notice above and the following disclaimer of warranties; and
44 * 2. No rights are granted, in any manner or form, to use Whistle
45 *    Communications, Inc. trademarks, including the mark "WHISTLE
46 *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
47 *    such appears in the above copyright notice or in the software.
48 *
49 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
50 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
51 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
52 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
53 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
54 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
55 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
56 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
57 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
58 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
59 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
60 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
61 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
62 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
63 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
64 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
65 * OF SUCH DAMAGE.
66 *
67 * $FreeBSD$
68 */
69
70/*
71 * ng_gif_demux(4) netgraph node type
72 *
73 * Packets received on the "gif" hook have their type header removed
74 * and are passed to the appropriate hook protocol hook.  Packets
75 * received on a protocol hook have a type header added back and are
76 * passed out the gif hook. The currently supported protocol hooks are:
77 */
78
79#include <sys/param.h>
80#include <sys/systm.h>
81#include <sys/kernel.h>
82#include <sys/malloc.h>
83#include <sys/ctype.h>
84#include <sys/mbuf.h>
85#include <sys/errno.h>
86#include <sys/socket.h>
87
88#include <netgraph/ng_message.h>
89#include <netgraph/netgraph.h>
90#include <netgraph/ng_parse.h>
91#include <netgraph/ng_gif_demux.h>
92
93#ifdef NG_SEPARATE_MALLOC
94static MALLOC_DEFINE(M_NETGRAPH_GIF_DEMUX, "netgraph_gif_demux",
95    "netgraph gif demux node");
96#else
97#define M_NETGRAPH_GIF_DEMUX M_NETGRAPH
98#endif
99
100/* This struct describes one address family */
101struct iffam {
102	sa_family_t	family;		/* Address family */
103	const char	*hookname;	/* Name for hook */
104};
105typedef const struct iffam *iffam_p;
106
107/* List of address families supported by our interface */
108const static struct iffam gFamilies[] = {
109	{ AF_INET,	NG_GIF_DEMUX_HOOK_INET	},
110	{ AF_INET6,	NG_GIF_DEMUX_HOOK_INET6	},
111	{ AF_APPLETALK,	NG_GIF_DEMUX_HOOK_ATALK	},
112	{ AF_IPX,	NG_GIF_DEMUX_HOOK_IPX	},
113	{ AF_ATM,	NG_GIF_DEMUX_HOOK_ATM	},
114	{ AF_NATM,	NG_GIF_DEMUX_HOOK_NATM	},
115};
116#define	NUM_FAMILIES		nitems(gFamilies)
117
118/* Per-node private data */
119struct ng_gif_demux_private {
120	node_p	node;			/* Our netgraph node */
121	hook_p	gif;			/* The gif hook */
122	hook_p	hooks[NUM_FAMILIES];	/* The protocol hooks */
123};
124typedef struct ng_gif_demux_private *priv_p;
125
126/* Netgraph node methods */
127static ng_constructor_t	ng_gif_demux_constructor;
128static ng_rcvmsg_t	ng_gif_demux_rcvmsg;
129static ng_shutdown_t	ng_gif_demux_shutdown;
130static ng_newhook_t	ng_gif_demux_newhook;
131static ng_rcvdata_t	ng_gif_demux_rcvdata;
132static ng_disconnect_t	ng_gif_demux_disconnect;
133
134/* Helper stuff */
135static iffam_p	get_iffam_from_af(sa_family_t family);
136static iffam_p	get_iffam_from_hook(priv_p priv, hook_p hook);
137static iffam_p	get_iffam_from_name(const char *name);
138static hook_p	*get_hook_from_iffam(priv_p priv, iffam_p iffam);
139
140/******************************************************************
141		    NETGRAPH PARSE TYPES
142******************************************************************/
143
144/* List of commands and how to convert arguments to/from ASCII */
145static const struct ng_cmdlist ng_gif_demux_cmdlist[] = {
146	{ 0 }
147};
148
149/* Node type descriptor */
150static struct ng_type ng_gif_demux_typestruct = {
151	.version =	NG_ABI_VERSION,
152	.name =		NG_GIF_DEMUX_NODE_TYPE,
153	.constructor =	ng_gif_demux_constructor,
154	.rcvmsg =	ng_gif_demux_rcvmsg,
155	.shutdown =	ng_gif_demux_shutdown,
156	.newhook =	ng_gif_demux_newhook,
157	.rcvdata =	ng_gif_demux_rcvdata,
158	.disconnect =	ng_gif_demux_disconnect,
159	.cmdlist =	ng_gif_demux_cmdlist,
160};
161NETGRAPH_INIT(gif_demux, &ng_gif_demux_typestruct);
162
163/************************************************************************
164		    HELPER STUFF
165 ************************************************************************/
166
167/*
168 * Get the family descriptor from the family ID
169 */
170static __inline iffam_p
171get_iffam_from_af(sa_family_t family)
172{
173	iffam_p iffam;
174	int k;
175
176	for (k = 0; k < NUM_FAMILIES; k++) {
177		iffam = &gFamilies[k];
178		if (iffam->family == family)
179			return (iffam);
180	}
181	return (NULL);
182}
183
184/*
185 * Get the family descriptor from the hook
186 */
187static __inline iffam_p
188get_iffam_from_hook(priv_p priv, hook_p hook)
189{
190	int k;
191
192	for (k = 0; k < NUM_FAMILIES; k++)
193		if (priv->hooks[k] == hook)
194			return (&gFamilies[k]);
195	return (NULL);
196}
197
198/*
199 * Get the hook from the iffam descriptor
200 */
201
202static __inline hook_p *
203get_hook_from_iffam(priv_p priv, iffam_p iffam)
204{
205	return (&priv->hooks[iffam - gFamilies]);
206}
207
208/*
209 * Get the iffam descriptor from the name
210 */
211static __inline iffam_p
212get_iffam_from_name(const char *name)
213{
214	iffam_p iffam;
215	int k;
216
217	for (k = 0; k < NUM_FAMILIES; k++) {
218		iffam = &gFamilies[k];
219		if (!strcmp(iffam->hookname, name))
220			return (iffam);
221	}
222	return (NULL);
223}
224
225/******************************************************************
226		    NETGRAPH NODE METHODS
227******************************************************************/
228
229/*
230 * Node constructor
231 */
232static int
233ng_gif_demux_constructor(node_p node)
234{
235	priv_p priv;
236
237	/* Allocate and initialize private info */
238	priv = malloc(sizeof(*priv), M_NETGRAPH_GIF_DEMUX, M_WAITOK | M_ZERO);
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 */
250static	int
251ng_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 */
274static int
275ng_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 */
305static int
306ng_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), M_NOWAIT);
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 */
368static int
369ng_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 */
382static int
383ng_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("%s", __func__);
394		*get_hook_from_iffam(priv, iffam) = NULL;
395	}
396
397	return (0);
398}
399