summaryrefslogtreecommitdiffstats
path: root/sys/netgraph/ng_UI.c
blob: 21a10f577b5ef0b26a04760568a26095af7b95db (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243

/*
 * ng_UI.c
 *
 * Copyright (c) 1996-1999 Whistle Communications, Inc.
 * All rights reserved.
 * 
 * Subject to the following obligations and disclaimer of warranty, use and
 * redistribution of this software, in source or object code forms, with or
 * without modifications are expressly permitted by Whistle Communications;
 * provided, however, that:
 * 1. Any and all reproductions of the source or object code must include the
 *    copyright notice above and the following disclaimer of warranties; and
 * 2. No rights are granted, in any manner or form, to use Whistle
 *    Communications, Inc. trademarks, including the mark "WHISTLE
 *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
 *    such appears in the above copyright notice or in the software.
 * 
 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
 * OF SUCH DAMAGE.
 *
 * Author: Julian Elischer <julian@whistle.com>
 *
 * $FreeBSD$
 * $Whistle: ng_UI.c,v 1.14 1999/11/01 09:24:51 julian Exp $
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/errno.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/conf.h>
#include <sys/errno.h>
#include <sys/socket.h>
#include <sys/syslog.h>

#include <net/if.h>
#include <netinet/in.h>
#include <netinet/if_ether.h>

#include <netgraph/ng_message.h>
#include <netgraph/netgraph.h>
#include <netgraph/ng_UI.h>

/*
 * DEFINITIONS
 */

/* Everything, starting with sdlc on has defined UI as 0x03 */
#define HDLC_UI	0x03

/* Node private data */
struct ng_UI_private {
	hook_p  downlink;
	hook_p  uplink;
};
typedef struct ng_UI_private *priv_p;

/* Netgraph node methods */
static ng_constructor_t	ng_UI_constructor;
static ng_rcvmsg_t	ng_UI_rcvmsg;
static ng_shutdown_t	ng_UI_rmnode;
static ng_newhook_t	ng_UI_newhook;
static ng_rcvdata_t	ng_UI_rcvdata;
static ng_disconnect_t	ng_UI_disconnect;

/* Node type descriptor */
static struct ng_type typestruct = {
	NG_VERSION,
	NG_UI_NODE_TYPE,
	NULL,
	ng_UI_constructor,
	ng_UI_rcvmsg,
	ng_UI_rmnode,
	ng_UI_newhook,
	NULL,
	NULL,
	ng_UI_rcvdata,
	ng_UI_rcvdata,
	ng_UI_disconnect,
	NULL
};
NETGRAPH_INIT(UI, &typestruct);

/************************************************************************
			NETGRAPH NODE STUFF
 ************************************************************************/

/*
 * Create a newborn node. We start with an implicit reference.
 */

static int
ng_UI_constructor(node_p *nodep)
{
	priv_p  priv;
	int     error;

	/* Allocate private structure */
	MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_WAITOK);
	if (priv == NULL)
		return (ENOMEM);
	bzero(priv, sizeof(*priv));

	/* Call generic node constructor */
	if ((error = ng_make_node_common(&typestruct, nodep))) {
		FREE(priv, M_NETGRAPH);
		return (error);
	}
	(*nodep)->private = priv;

	/* Done */
	return (0);
}

/*
 * Give our ok for a hook to be added
 */
static int
ng_UI_newhook(node_p node, hook_p hook, const char *name)
{
	const priv_p priv = node->private;

	if (!strcmp(name, NG_UI_HOOK_DOWNSTREAM)) {
		if (priv->downlink)
			return (EISCONN);
		priv->downlink = hook;
	} else if (!strcmp(name, NG_UI_HOOK_UPSTREAM)) {
		if (priv->uplink)
			return (EISCONN);
		priv->uplink = hook;
	} else
		return (EINVAL);
	return (0);
}

/*
 * Receive a control message
 */
static int
ng_UI_rcvmsg(node_p node, struct ng_mesg *msg,
	     const char *raddr, struct ng_mesg **rp)
{
	FREE(msg, M_NETGRAPH);
	return (EINVAL);
}

#define MAX_ENCAPS_HDR	1
#define ERROUT(x)	do { error = (x); goto done; } while (0)

/*
 * Receive a data frame
 */
static int
ng_UI_rcvdata(hook_p hook, struct mbuf *m, meta_p meta)
{
	const node_p node = hook->node;
	const priv_p priv = node->private;
	int error = 0;

	if (hook == priv->downlink) {
		u_char *start, *ptr;

		if (!m || (m->m_len < MAX_ENCAPS_HDR
		    && !(m = m_pullup(m, MAX_ENCAPS_HDR))))
			ERROUT(ENOBUFS);
		ptr = start = mtod(m, u_char *);

		/* Must be UI frame */
		if (*ptr++ != HDLC_UI)
			ERROUT(0);

		m_adj(m, ptr - start);
		NG_SEND_DATA(error, priv->uplink, m, meta);	/* m -> NULL */
	} else if (hook == priv->uplink) {
		M_PREPEND(m, 1, M_DONTWAIT);	/* Prepend IP NLPID */
		if (!m)
			ERROUT(ENOBUFS);
		mtod(m, u_char *)[0] = HDLC_UI;
		NG_SEND_DATA(error, priv->downlink, m, meta);	/* m -> NULL */
	} else
		panic(__FUNCTION__);

done:
	NG_FREE_DATA(m, meta);	/* does nothing if m == NULL */
	return (error);
}

/*
 * Shutdown node
 */
static int
ng_UI_rmnode(node_p node)
{
	const priv_p priv = node->private;

	/* Take down netgraph node */
	node->flags |= NG_INVALID;
	ng_cutlinks(node);
	ng_unname(node);
	bzero(priv, sizeof(*priv));
	FREE(priv, M_NETGRAPH);
	node->private = NULL;
	ng_unref(node);
	return (0);
}

/*
 * Hook disconnection
 */
static int
ng_UI_disconnect(hook_p hook)
{
	const priv_p priv = hook->node->private;

	if (hook->node->numhooks == 0)
		ng_rmnode(hook->node);
	else if (hook == priv->downlink)
		priv->downlink = NULL;
	else if (hook == priv->uplink)
		priv->uplink = NULL;
	else
		panic(__FUNCTION__);
	return (0);
}

OpenPOWER on IntegriCloud