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
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 * received 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 <netgraph/ng_message.h>
87#include <netgraph/netgraph.h>
88#include <netgraph/ng_parse.h>
89#include <netgraph/ng_gif_demux.h>
90
91#ifdef NG_SEPARATE_MALLOC
92static 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 */
99struct iffam {
100	sa_family_t	family;		/* Address family */
101	const char	*hookname;	/* Name for hook */
102};
103typedef const struct iffam *iffam_p;
104
105/* List of address families supported by our interface */
106const static struct iffam gFamilies[] = {
107	{ AF_INET,	NG_GIF_DEMUX_HOOK_INET	},
108	{ AF_INET6,	NG_GIF_DEMUX_HOOK_INET6	},
109	{ AF_APPLETALK,	NG_GIF_DEMUX_HOOK_ATALK	},
110	{ AF_IPX,	NG_GIF_DEMUX_HOOK_IPX	},
111	{ AF_ATM,	NG_GIF_DEMUX_HOOK_ATM	},
112	{ AF_NATM,	NG_GIF_DEMUX_HOOK_NATM	},
113};
114#define	NUM_FAMILIES		nitems(gFamilies)
115
116/* Per-node private data */
117struct ng_gif_demux_private {
118	node_p	node;			/* Our netgraph node */
119	hook_p	gif;			/* The gif hook */
120	hook_p	hooks[NUM_FAMILIES];	/* The protocol hooks */
121};
122typedef struct ng_gif_demux_private *priv_p;
123
124/* Netgraph node methods */
125static ng_constructor_t	ng_gif_demux_constructor;
126static ng_rcvmsg_t	ng_gif_demux_rcvmsg;
127static ng_shutdown_t	ng_gif_demux_shutdown;
128static ng_newhook_t	ng_gif_demux_newhook;
129static ng_rcvdata_t	ng_gif_demux_rcvdata;
130static ng_disconnect_t	ng_gif_demux_disconnect;
131
132/* Helper stuff */
133static iffam_p	get_iffam_from_af(sa_family_t family);
134static iffam_p	get_iffam_from_hook(priv_p priv, hook_p hook);
135static iffam_p	get_iffam_from_name(const char *name);
136static hook_p	*get_hook_from_iffam(priv_p priv, iffam_p iffam);
137
138/******************************************************************
139		    NETGRAPH PARSE TYPES
140******************************************************************/
141
142/* List of commands and how to convert arguments to/from ASCII */
143static const struct ng_cmdlist ng_gif_demux_cmdlist[] = {
144	{ 0 }
145};
146
147/* Node type descriptor */
148static struct ng_type ng_gif_demux_typestruct = {
149	.version =	NG_ABI_VERSION,
150	.name =		NG_GIF_DEMUX_NODE_TYPE,
151	.constructor =	ng_gif_demux_constructor,
152	.rcvmsg =	ng_gif_demux_rcvmsg,
153	.shutdown =	ng_gif_demux_shutdown,
154	.newhook =	ng_gif_demux_newhook,
155	.rcvdata =	ng_gif_demux_rcvdata,
156	.disconnect =	ng_gif_demux_disconnect,
157	.cmdlist =	ng_gif_demux_cmdlist,
158};
159NETGRAPH_INIT(gif_demux, &ng_gif_demux_typestruct);
160
161/************************************************************************
162		    HELPER STUFF
163 ************************************************************************/
164
165/*
166 * Get the family descriptor from the family ID
167 */
168static __inline iffam_p
169get_iffam_from_af(sa_family_t family)
170{
171	iffam_p iffam;
172	int k;
173
174	for (k = 0; k < NUM_FAMILIES; k++) {
175		iffam = &gFamilies[k];
176		if (iffam->family == family)
177			return (iffam);
178	}
179	return (NULL);
180}
181
182/*
183 * Get the family descriptor from the hook
184 */
185static __inline iffam_p
186get_iffam_from_hook(priv_p priv, hook_p hook)
187{
188	int k;
189
190	for (k = 0; k < NUM_FAMILIES; k++)
191		if (priv->hooks[k] == hook)
192			return (&gFamilies[k]);
193	return (NULL);
194}
195
196/*
197 * Get the hook from the iffam descriptor
198 */
199
200static __inline hook_p *
201get_hook_from_iffam(priv_p priv, iffam_p iffam)
202{
203	return (&priv->hooks[iffam - gFamilies]);
204}
205
206/*
207 * Get the iffam descriptor from the name
208 */
209static __inline iffam_p
210get_iffam_from_name(const char *name)
211{
212	iffam_p iffam;
213	int k;
214
215	for (k = 0; k < NUM_FAMILIES; k++) {
216		iffam = &gFamilies[k];
217		if (!strcmp(iffam->hookname, name))
218			return (iffam);
219	}
220	return (NULL);
221}
222
223/******************************************************************
224		    NETGRAPH NODE METHODS
225******************************************************************/
226
227/*
228 * Node constructor
229 */
230static int
231ng_gif_demux_constructor(node_p node)
232{
233	priv_p priv;
234
235	/* Allocate and initialize private info */
236	priv = malloc(sizeof(*priv), M_NETGRAPH_GIF_DEMUX, M_WAITOK | M_ZERO);
237	priv->node = node;
238
239	NG_NODE_SET_PRIVATE(node, priv);
240
241	/* Done */
242	return (0);
243}
244
245/*
246 * Method for attaching a new hook
247 */
248static	int
249ng_gif_demux_newhook(node_p node, hook_p hook, const char *name)
250{
251	const priv_p priv = NG_NODE_PRIVATE(node);
252	iffam_p iffam;
253	hook_p *hookptr;
254
255	if (strcmp(NG_GIF_DEMUX_HOOK_GIF, name) == 0)
256		hookptr = &priv->gif;
257	else {
258		iffam = get_iffam_from_name(name);
259		if (iffam == NULL)
260			return (EPFNOSUPPORT);
261		hookptr = get_hook_from_iffam(NG_NODE_PRIVATE(node), iffam);
262	}
263	if (*hookptr != NULL)
264		return (EISCONN);
265	*hookptr = hook;
266	return (0);
267}
268
269/*
270 * Receive a control message
271 */
272static int
273ng_gif_demux_rcvmsg(node_p node, item_p item, hook_p lasthook)
274{
275	struct ng_mesg *resp = NULL;
276	int error = 0;
277	struct ng_mesg *msg;
278
279	NGI_GET_MSG(item, msg);
280	switch (msg->header.typecookie) {
281	case NGM_GIF_DEMUX_COOKIE:
282		switch (msg->header.cmd) {
283		/* XXX: Add commands here. */
284		default:
285			error = EINVAL;
286			break;
287		}
288		break;
289	default:
290		error = EINVAL;
291		break;
292	}
293
294	/* Done */
295	NG_RESPOND_MSG(error, node, item, resp);
296	NG_FREE_MSG(msg);
297	return (error);
298}
299
300/*
301 * Receive data on a hook
302 */
303static int
304ng_gif_demux_rcvdata(hook_p hook, item_p item)
305{
306	const node_p node = NG_HOOK_NODE(hook);
307	const priv_p priv = NG_NODE_PRIVATE(node);
308	iffam_p iffam;
309	hook_p outhook;
310	int error = 0;
311	struct mbuf *m;
312
313	/* Pull the mbuf out of the item for processing. */
314	NGI_GET_M(item, m);
315
316	if (hook == priv->gif) {
317		/*
318		 * Pull off the address family header and find the
319		 * output hook.
320		 */
321		if (m->m_pkthdr.len < sizeof(sa_family_t)) {
322			NG_FREE_M(m);
323			NG_FREE_ITEM(item);
324			return (EINVAL);
325		}
326		if (m->m_len < sizeof(sa_family_t)
327		    && (m = m_pullup(m, sizeof(sa_family_t))) == NULL) {
328			NG_FREE_ITEM(item);
329			return (ENOBUFS);
330		}
331		iffam = get_iffam_from_af(*mtod(m, sa_family_t *));
332		if (iffam == NULL) {
333			NG_FREE_M(m);
334			NG_FREE_ITEM(item);
335			return (EINVAL);
336		}
337		outhook = *get_hook_from_iffam(priv, iffam);
338		m_adj(m, sizeof(sa_family_t));
339	} else {
340		/*
341		 * Add address family header and set the output hook.
342		 */
343		iffam = get_iffam_from_hook(priv, hook);
344		M_PREPEND(m, sizeof (iffam->family), M_NOWAIT);
345		if (m == NULL) {
346			NG_FREE_M(m);
347			NG_FREE_ITEM(item);
348			return (ENOBUFS);
349		}
350		bcopy(&iffam->family, mtod(m, sa_family_t *),
351		    sizeof(iffam->family));
352		outhook = priv->gif;
353	}
354
355	/* Stuff the mbuf back in. */
356	NGI_M(item) = m;
357
358	/* Deliver packet */
359	NG_FWD_ITEM_HOOK(error, item, outhook);
360	return (error);
361}
362
363/*
364 * Shutdown node
365 */
366static int
367ng_gif_demux_shutdown(node_p node)
368{
369	const priv_p priv = NG_NODE_PRIVATE(node);
370
371	free(priv, M_NETGRAPH_GIF_DEMUX);
372	NG_NODE_SET_PRIVATE(node, NULL);
373	NG_NODE_UNREF(node);
374	return (0);
375}
376
377/*
378 * Hook disconnection.
379 */
380static int
381ng_gif_demux_disconnect(hook_p hook)
382{
383	const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
384	iffam_p iffam;
385
386	if (hook == priv->gif)
387		priv->gif = NULL;
388	else {
389		iffam = get_iffam_from_hook(priv, hook);
390		if (iffam == NULL)
391			panic("%s", __func__);
392		*get_hook_from_iffam(priv, iffam) = NULL;
393	}
394
395	return (0);
396}
397