2 * Copyright (c) 1991, 1993, 1994, 1995, 1996, 1997
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that: (1) source code distributions
7 * retain the above copyright notice and this paragraph in its entirety, (2)
8 * distributions including binary code include the above copyright notice and
9 * this paragraph in its entirety in the documentation or other materials
10 * provided with the distribution, and (3) all advertising materials mentioning
11 * features or use of this software display the following acknowledgement:
12 * ``This product includes software developed by the University of California,
13 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14 * the University nor the names of its contributors may be used to endorse
15 * or promote products derived from this software without specific prior
17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
25 static const char rcsid[] _U_ =
26 "@(#) $Header: /tcpdump/master/tcpdump/print-null.c,v 1.53 2005/04/06 21:32:41 mcr Exp $ (LBL)";
33 #include <tcpdump-stdinc.h>
39 #include "interface.h"
40 #include "addrtoname.h"
48 * The DLT_NULL packet header is 4 bytes long. It contains a host-byte-order
49 * 32-bit integer that specifies the family, e.g. AF_INET.
51 * Note here that "host" refers to the host on which the packets were
52 * captured; that isn't necessarily *this* host.
54 * The OpenBSD DLT_LOOP packet header is the same, except that the integer
55 * is in network byte order.
62 * Unfortunately, the BSDs don't all use the same value for AF_INET6,
63 * so, because we want to be able to read captures from all of the BSDs,
64 * we check for all of them.
67 #define BSD_AF_NS 6 /* XEROX NS protocols */
69 #define BSD_AF_APPLETALK 16
71 #define BSD_AF_INET6_BSD 24 /* OpenBSD (and probably NetBSD), BSD/OS */
72 #define BSD_AF_INET6_FREEBSD 28
73 #define BSD_AF_INET6_DARWIN 30
76 null_print(u_int family, u_int length)
79 printf("AF %u ", family);
88 case BSD_AF_INET6_BSD:
89 case BSD_AF_INET6_FREEBSD:
90 case BSD_AF_INET6_DARWIN:
103 case BSD_AF_APPLETALK:
112 printf("AF %u ", family);
116 printf("%d: ", length);
120 * Byte-swap a 32-bit number.
121 * ("htonl()" or "ntohl()" won't work - we want to byte-swap even on
122 * big-endian platforms.)
124 #define SWAPLONG(y) \
125 ((((y)&0xff)<<24) | (((y)&0xff00)<<8) | (((y)&0xff0000)>>8) | (((y)>>24)&0xff))
128 * This is the top level routine of the printer. 'p' points
129 * to the ether header of the packet, 'h->ts' is the timestamp,
130 * 'h->len' is the length of the packet off the wire, and 'h->caplen'
131 * is the number of bytes actually captured.
134 null_if_print(const struct pcap_pkthdr *h, const u_char *p)
136 u_int length = h->len;
137 u_int caplen = h->caplen;
140 if (caplen < NULL_HDRLEN) {
142 return (NULL_HDRLEN);
145 memcpy((char *)&family, (char *)p, sizeof(family));
148 * This isn't necessarily in our host byte order; if this is
149 * a DLT_LOOP capture, it's in network byte order, and if
150 * this is a DLT_NULL capture from a machine with the opposite
151 * byte-order, it's in the opposite byte order from ours.
153 * If the upper 16 bits aren't all zero, assume it's byte-swapped.
155 if ((family & 0xFFFF0000) != 0)
156 family = SWAPLONG(family);
158 length -= NULL_HDRLEN;
159 caplen -= NULL_HDRLEN;
163 null_print(family, length);
168 ip_print(gndo, p, length);
172 case BSD_AF_INET6_BSD:
173 case BSD_AF_INET6_FREEBSD:
174 case BSD_AF_INET6_DARWIN:
175 ip6_print(p, length);
180 isoclns_print(p, length, caplen);
183 case BSD_AF_APPLETALK:
184 atalk_print(p, length);
188 ipx_print(p, length);
192 /* unknown AF_ value */
194 null_print(family, length + NULL_HDRLEN);
195 if (!xflag && !qflag)
196 default_print(p, caplen);
199 return (NULL_HDRLEN);
204 * c-style: whitesmith