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
|
/*
* Copyright (c) 1991, 1993, 1994, 1995, 1996, 1997
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that: (1) source code distributions
* retain the above copyright notice and this paragraph in its entirety, (2)
* distributions including binary code include the above copyright notice and
* this paragraph in its entirety in the documentation or other materials
* provided with the distribution, and (3) all advertising materials mentioning
* features or use of this software display the following acknowledgement:
* ``This product includes software developed by the University of California,
* Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
* the University nor the names of its contributors may be used to endorse
* or promote products derived from this software without specific prior
* written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
#ifndef lint
static const char rcsid[] _U_ =
"@(#) $Header: /tcpdump/master/tcpdump/print-null.c,v 1.57 2006-03-23 14:58:44 hannes Exp $ (LBL)";
#endif
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <tcpdump-stdinc.h>
#include <pcap.h>
#include <stdio.h>
#include <string.h>
#include "interface.h"
#include "addrtoname.h"
#include "ip.h"
#ifdef INET6
#include "ip6.h"
#endif
#include "af.h"
/*
* The DLT_NULL packet header is 4 bytes long. It contains a host-byte-order
* 32-bit integer that specifies the family, e.g. AF_INET.
*
* Note here that "host" refers to the host on which the packets were
* captured; that isn't necessarily *this* host.
*
* The OpenBSD DLT_LOOP packet header is the same, except that the integer
* is in network byte order.
*/
#define NULL_HDRLEN 4
/*
* Byte-swap a 32-bit number.
* ("htonl()" or "ntohl()" won't work - we want to byte-swap even on
* big-endian platforms.)
*/
#define SWAPLONG(y) \
((((y)&0xff)<<24) | (((y)&0xff00)<<8) | (((y)&0xff0000)>>8) | (((y)>>24)&0xff))
static inline void
null_hdr_print(u_int family, u_int length)
{
if (!qflag) {
(void)printf("AF %s (%u)",
tok2str(bsd_af_values,"Unknown",family),family);
} else {
(void)printf("%s",
tok2str(bsd_af_values,"Unknown AF %u",family));
}
(void)printf(", length %u: ", length);
}
/*
* This is the top level routine of the printer. 'p' points
* to the ether header of the packet, 'h->ts' is the timestamp,
* 'h->len' is the length of the packet off the wire, and 'h->caplen'
* is the number of bytes actually captured.
*/
u_int
null_if_print(const struct pcap_pkthdr *h, const u_char *p)
{
u_int length = h->len;
u_int caplen = h->caplen;
u_int family;
if (caplen < NULL_HDRLEN) {
printf("[|null]");
return (NULL_HDRLEN);
}
memcpy((char *)&family, (char *)p, sizeof(family));
/*
* This isn't necessarily in our host byte order; if this is
* a DLT_LOOP capture, it's in network byte order, and if
* this is a DLT_NULL capture from a machine with the opposite
* byte-order, it's in the opposite byte order from ours.
*
* If the upper 16 bits aren't all zero, assume it's byte-swapped.
*/
if ((family & 0xFFFF0000) != 0)
family = SWAPLONG(family);
if (eflag)
null_hdr_print(family, length);
length -= NULL_HDRLEN;
caplen -= NULL_HDRLEN;
p += NULL_HDRLEN;
switch (family) {
case BSD_AFNUM_INET:
ip_print(gndo, p, length);
break;
#ifdef INET6
case BSD_AFNUM_INET6_BSD:
case BSD_AFNUM_INET6_FREEBSD:
case BSD_AFNUM_INET6_DARWIN:
ip6_print(gndo, p, length);
break;
#endif
case BSD_AFNUM_ISO:
isoclns_print(p, length, caplen);
break;
case BSD_AFNUM_APPLETALK:
atalk_print(p, length);
break;
case BSD_AFNUM_IPX:
ipx_print(p, length);
break;
default:
/* unknown AF_ value */
if (!eflag)
null_hdr_print(family, length + NULL_HDRLEN);
if (!suppress_default_print)
default_print(p, caplen);
}
return (NULL_HDRLEN);
}
/*
* Local Variables:
* c-style: whitesmith
* c-basic-offset: 8
* End:
*/
|
