1/*	$NetBSD: get.c,v 1.5 2009/10/20 00:51:13 snj Exp $	*/
2
3/*
4 * Copyright (c) 1993-95 Mats O Jansson.  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, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28#ifndef lint
29__RCSID("$NetBSD: get.c,v 1.5 2009/10/20 00:51:13 snj Exp $");
30#endif
31
32#include "os.h"
33#include "get.h"
34#include "mopdef.h"
35
36u_char
37mopGetChar(const u_char *pkt, int *idx)
38{
39        u_char ret;
40
41	ret = pkt[*idx];
42	*idx = *idx + 1;
43	return(ret);
44}
45
46u_short
47mopGetShort(const u_char *pkt, int *idx)
48{
49        u_short ret;
50
51	ret = pkt[*idx] + pkt[*idx+1]*256;
52	*idx = *idx + 2;
53	return(ret);
54}
55
56u_int32_t
57mopGetLong(const u_char *pkt, int *idx)
58{
59        u_int32_t ret;
60
61	ret = pkt[*idx] +
62	      pkt[*idx+1]*0x100 +
63	      pkt[*idx+2]*0x10000 +
64	      pkt[*idx+3]*0x1000000;
65	*idx = *idx + 4;
66	return(ret);
67}
68
69void
70mopGetMulti(const u_char *pkt, int *idx, u_char *dest, int size)
71{
72	int i;
73
74	for (i = 0; i < size; i++) {
75	  dest[i] = pkt[*idx+i];
76	}
77	*idx = *idx + size;
78
79}
80
81int
82mopGetTrans(const u_char *pkt, int trans)
83{
84	const u_short	*ptype;
85
86	if (trans == 0) {
87		ptype = (const u_short *)(pkt+12);
88		if (ntohs(*ptype) < 1600) {
89			trans = TRANS_8023;
90		} else {
91			trans = TRANS_ETHER;
92		}
93	}
94	return(trans);
95}
96
97void
98mopGetHeader(const u_char *pkt, int *idx, const u_char **dst, const u_char **src,
99	     u_short *proto, int *len, int trans)
100{
101	*dst = pkt;
102	*src = pkt + 6;
103	*idx = *idx + 12;
104
105	switch(trans) {
106	case TRANS_ETHER:
107		*proto = (u_short)(pkt[*idx]*256 + pkt[*idx+1]);
108		*idx = *idx + 2;
109		*len   = (int)(pkt[*idx+1]*256 + pkt[*idx]);
110		*idx = *idx + 2;
111		break;
112	case TRANS_8023:
113		*len   = (int)(pkt[*idx]*256 + pkt[*idx+1]);
114		*idx = *idx + 8;
115		*proto = (u_short)(pkt[*idx]*256 + pkt[*idx+1]);
116		*idx = *idx + 2;
117		break;
118	}
119}
120
121u_short
122mopGetLength(const u_char *pkt, int trans)
123{
124	switch(trans) {
125	case TRANS_ETHER:
126		return(pkt[15]*256 + pkt[14]);
127		break;
128	case TRANS_8023:
129		return(pkt[12]*256 + pkt[13]);
130		break;
131	}
132	return(0);
133}
134