get.c revision 1.4 
1/*	$OpenBSD: get.c,v 1.4 2003/06/02 21:38:39 maja 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#ifndef LINT
28static char rcsid[] = "$OpenBSD: get.c,v 1.4 2003/06/02 21:38:39 maja Exp $";
29#endif
30
31#include <sys/types.h>
32#include "common/mopdef.h"
33
34u_char
35mopGetChar(pkt, index)
36	u_char *pkt;
37	int    *index;
38{
39        u_char ret;
40
41	ret = pkt[*index];
42	*index = *index + 1;
43	return(ret);
44}
45
46u_short
47mopGetShort(pkt, index)
48	u_char *pkt;
49	int    *index;
50{
51        u_short ret;
52
53	ret = pkt[*index] + pkt[*index+1]*256;
54	*index = *index + 2;
55	return(ret);
56}
57
58u_long
59mopGetLong(pkt, index)
60	u_char *pkt;
61	int    *index;
62{
63        u_long ret;
64
65	ret = pkt[*index] +
66	      pkt[*index+1]*0x100 +
67	      pkt[*index+2]*0x10000 +
68	      pkt[*index+3]*0x1000000;
69	*index = *index + 4;
70	return(ret);
71}
72
73void
74mopGetMulti(pkt, index, dest, size)
75	u_char *pkt,*dest;
76	int    *index,size;
77{
78	int i;
79
80	for (i = 0; i < size; i++) {
81	  dest[i] = pkt[*index+i];
82	}
83	*index = *index + size;
84
85}
86
87int
88mopGetTrans(pkt, trans)
89	u_char	*pkt;
90	int	 trans;
91{
92	u_short	*ptype;
93
94	if (trans == 0) {
95		ptype = (u_short *)(pkt+12);
96		if (ntohs(*ptype) < 1600) {
97			trans = TRANS_8023;
98		} else {
99			trans = TRANS_ETHER;
100		}
101	}
102	return(trans);
103}
104
105void
106mopGetHeader(pkt, index, dst, src, proto, len, trans)
107	u_char	*pkt, **dst, **src;
108	int	*index, *len, trans;
109	u_short	*proto;
110{
111	*dst = pkt;
112	*src = pkt + 6;
113	*index = *index + 12;
114
115	switch(trans) {
116	case TRANS_ETHER:
117		*proto = (u_short)(pkt[*index]*256 + pkt[*index+1]);
118		*index = *index + 2;
119		*len   = (int)(pkt[*index+1]*256 + pkt[*index]);
120		*index = *index + 2;
121		break;
122	case TRANS_8023:
123		*len   = (int)(pkt[*index]*256 + pkt[*index+1]);
124		*index = *index + 8;
125		*proto = (u_short)(pkt[*index]*256 + pkt[*index+1]);
126		*index = *index + 2;
127		break;
128	}
129}
130
131u_short
132mopGetLength(pkt, trans)
133	u_char	*pkt;
134	int	 trans;
135{
136	switch(trans) {
137	case TRANS_ETHER:
138		return(pkt[15]*256 + pkt[14]);
139		break;
140	case TRANS_8023:
141		return(pkt[12]*256 + pkt[13]);
142		break;
143	}
144	return(0);
145}
146