xref: /minix3/external/bsd/tcpdump/dist/print-null.c (revision b636d99d91c3d54204248f643c14627405d4afd1)
1*b636d99dSDavid van Moolenbroek /*
2*b636d99dSDavid van Moolenbroek  * Copyright (c) 1991, 1993, 1994, 1995, 1996, 1997
3*b636d99dSDavid van Moolenbroek  *	The Regents of the University of California.  All rights reserved.
4*b636d99dSDavid van Moolenbroek  *
5*b636d99dSDavid van Moolenbroek  * Redistribution and use in source and binary forms, with or without
6*b636d99dSDavid van Moolenbroek  * modification, are permitted provided that: (1) source code distributions
7*b636d99dSDavid van Moolenbroek  * retain the above copyright notice and this paragraph in its entirety, (2)
8*b636d99dSDavid van Moolenbroek  * distributions including binary code include the above copyright notice and
9*b636d99dSDavid van Moolenbroek  * this paragraph in its entirety in the documentation or other materials
10*b636d99dSDavid van Moolenbroek  * provided with the distribution, and (3) all advertising materials mentioning
11*b636d99dSDavid van Moolenbroek  * features or use of this software display the following acknowledgement:
12*b636d99dSDavid van Moolenbroek  * ``This product includes software developed by the University of California,
13*b636d99dSDavid van Moolenbroek  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14*b636d99dSDavid van Moolenbroek  * the University nor the names of its contributors may be used to endorse
15*b636d99dSDavid van Moolenbroek  * or promote products derived from this software without specific prior
16*b636d99dSDavid van Moolenbroek  * written permission.
17*b636d99dSDavid van Moolenbroek  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18*b636d99dSDavid van Moolenbroek  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19*b636d99dSDavid van Moolenbroek  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20*b636d99dSDavid van Moolenbroek  */
21*b636d99dSDavid van Moolenbroek 
22*b636d99dSDavid van Moolenbroek #include <sys/cdefs.h>
23*b636d99dSDavid van Moolenbroek #ifndef lint
24*b636d99dSDavid van Moolenbroek __RCSID("$NetBSD: print-null.c,v 1.5 2015/03/31 21:59:35 christos Exp $");
25*b636d99dSDavid van Moolenbroek #endif
26*b636d99dSDavid van Moolenbroek 
27*b636d99dSDavid van Moolenbroek #define NETDISSECT_REWORKED
28*b636d99dSDavid van Moolenbroek #ifdef HAVE_CONFIG_H
29*b636d99dSDavid van Moolenbroek #include "config.h"
30*b636d99dSDavid van Moolenbroek #endif
31*b636d99dSDavid van Moolenbroek 
32*b636d99dSDavid van Moolenbroek #include <tcpdump-stdinc.h>
33*b636d99dSDavid van Moolenbroek 
34*b636d99dSDavid van Moolenbroek #include <string.h>
35*b636d99dSDavid van Moolenbroek 
36*b636d99dSDavid van Moolenbroek #include "interface.h"
37*b636d99dSDavid van Moolenbroek #include "af.h"
38*b636d99dSDavid van Moolenbroek 
39*b636d99dSDavid van Moolenbroek /*
40*b636d99dSDavid van Moolenbroek  * The DLT_NULL packet header is 4 bytes long. It contains a host-byte-order
41*b636d99dSDavid van Moolenbroek  * 32-bit integer that specifies the family, e.g. AF_INET.
42*b636d99dSDavid van Moolenbroek  *
43*b636d99dSDavid van Moolenbroek  * Note here that "host" refers to the host on which the packets were
44*b636d99dSDavid van Moolenbroek  * captured; that isn't necessarily *this* host.
45*b636d99dSDavid van Moolenbroek  *
46*b636d99dSDavid van Moolenbroek  * The OpenBSD DLT_LOOP packet header is the same, except that the integer
47*b636d99dSDavid van Moolenbroek  * is in network byte order.
48*b636d99dSDavid van Moolenbroek  */
49*b636d99dSDavid van Moolenbroek #define	NULL_HDRLEN 4
50*b636d99dSDavid van Moolenbroek 
51*b636d99dSDavid van Moolenbroek /*
52*b636d99dSDavid van Moolenbroek  * Byte-swap a 32-bit number.
53*b636d99dSDavid van Moolenbroek  * ("htonl()" or "ntohl()" won't work - we want to byte-swap even on
54*b636d99dSDavid van Moolenbroek  * big-endian platforms.)
55*b636d99dSDavid van Moolenbroek  */
56*b636d99dSDavid van Moolenbroek #define	SWAPLONG(y) \
57*b636d99dSDavid van Moolenbroek ((((y)&0xff)<<24) | (((y)&0xff00)<<8) | (((y)&0xff0000)>>8) | (((y)>>24)&0xff))
58*b636d99dSDavid van Moolenbroek 
59*b636d99dSDavid van Moolenbroek static inline void
null_hdr_print(netdissect_options * ndo,u_int family,u_int length)60*b636d99dSDavid van Moolenbroek null_hdr_print(netdissect_options *ndo, u_int family, u_int length)
61*b636d99dSDavid van Moolenbroek {
62*b636d99dSDavid van Moolenbroek 	if (!ndo->ndo_qflag) {
63*b636d99dSDavid van Moolenbroek 		ND_PRINT((ndo, "AF %s (%u)",
64*b636d99dSDavid van Moolenbroek 			tok2str(bsd_af_values,"Unknown",family),family));
65*b636d99dSDavid van Moolenbroek 	} else {
66*b636d99dSDavid van Moolenbroek 		ND_PRINT((ndo, "%s",
67*b636d99dSDavid van Moolenbroek 			tok2str(bsd_af_values,"Unknown AF %u",family)));
68*b636d99dSDavid van Moolenbroek 	}
69*b636d99dSDavid van Moolenbroek 
70*b636d99dSDavid van Moolenbroek 	ND_PRINT((ndo, ", length %u: ", length));
71*b636d99dSDavid van Moolenbroek }
72*b636d99dSDavid van Moolenbroek 
73*b636d99dSDavid van Moolenbroek /*
74*b636d99dSDavid van Moolenbroek  * This is the top level routine of the printer.  'p' points
75*b636d99dSDavid van Moolenbroek  * to the ether header of the packet, 'h->ts' is the timestamp,
76*b636d99dSDavid van Moolenbroek  * 'h->len' is the length of the packet off the wire, and 'h->caplen'
77*b636d99dSDavid van Moolenbroek  * is the number of bytes actually captured.
78*b636d99dSDavid van Moolenbroek  */
79*b636d99dSDavid van Moolenbroek u_int
null_if_print(netdissect_options * ndo,const struct pcap_pkthdr * h,const u_char * p)80*b636d99dSDavid van Moolenbroek null_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, const u_char *p)
81*b636d99dSDavid van Moolenbroek {
82*b636d99dSDavid van Moolenbroek 	u_int length = h->len;
83*b636d99dSDavid van Moolenbroek 	u_int caplen = h->caplen;
84*b636d99dSDavid van Moolenbroek 	u_int family;
85*b636d99dSDavid van Moolenbroek 
86*b636d99dSDavid van Moolenbroek 	if (caplen < NULL_HDRLEN) {
87*b636d99dSDavid van Moolenbroek 		ND_PRINT((ndo, "[|null]"));
88*b636d99dSDavid van Moolenbroek 		return (NULL_HDRLEN);
89*b636d99dSDavid van Moolenbroek 	}
90*b636d99dSDavid van Moolenbroek 
91*b636d99dSDavid van Moolenbroek 	memcpy((char *)&family, (char *)p, sizeof(family));
92*b636d99dSDavid van Moolenbroek 
93*b636d99dSDavid van Moolenbroek 	/*
94*b636d99dSDavid van Moolenbroek 	 * This isn't necessarily in our host byte order; if this is
95*b636d99dSDavid van Moolenbroek 	 * a DLT_LOOP capture, it's in network byte order, and if
96*b636d99dSDavid van Moolenbroek 	 * this is a DLT_NULL capture from a machine with the opposite
97*b636d99dSDavid van Moolenbroek 	 * byte-order, it's in the opposite byte order from ours.
98*b636d99dSDavid van Moolenbroek 	 *
99*b636d99dSDavid van Moolenbroek 	 * If the upper 16 bits aren't all zero, assume it's byte-swapped.
100*b636d99dSDavid van Moolenbroek 	 */
101*b636d99dSDavid van Moolenbroek 	if ((family & 0xFFFF0000) != 0)
102*b636d99dSDavid van Moolenbroek 		family = SWAPLONG(family);
103*b636d99dSDavid van Moolenbroek 
104*b636d99dSDavid van Moolenbroek 	if (ndo->ndo_eflag)
105*b636d99dSDavid van Moolenbroek 		null_hdr_print(ndo, family, length);
106*b636d99dSDavid van Moolenbroek 
107*b636d99dSDavid van Moolenbroek 	length -= NULL_HDRLEN;
108*b636d99dSDavid van Moolenbroek 	caplen -= NULL_HDRLEN;
109*b636d99dSDavid van Moolenbroek 	p += NULL_HDRLEN;
110*b636d99dSDavid van Moolenbroek 
111*b636d99dSDavid van Moolenbroek 	switch (family) {
112*b636d99dSDavid van Moolenbroek 
113*b636d99dSDavid van Moolenbroek 	case BSD_AFNUM_INET:
114*b636d99dSDavid van Moolenbroek 		ip_print(ndo, p, length);
115*b636d99dSDavid van Moolenbroek 		break;
116*b636d99dSDavid van Moolenbroek 
117*b636d99dSDavid van Moolenbroek 	case BSD_AFNUM_INET6_BSD:
118*b636d99dSDavid van Moolenbroek 	case BSD_AFNUM_INET6_FREEBSD:
119*b636d99dSDavid van Moolenbroek 	case BSD_AFNUM_INET6_DARWIN:
120*b636d99dSDavid van Moolenbroek 		ip6_print(ndo, p, length);
121*b636d99dSDavid van Moolenbroek 		break;
122*b636d99dSDavid van Moolenbroek 
123*b636d99dSDavid van Moolenbroek 	case BSD_AFNUM_ISO:
124*b636d99dSDavid van Moolenbroek 		isoclns_print(ndo, p, length, caplen);
125*b636d99dSDavid van Moolenbroek 		break;
126*b636d99dSDavid van Moolenbroek 
127*b636d99dSDavid van Moolenbroek 	case BSD_AFNUM_APPLETALK:
128*b636d99dSDavid van Moolenbroek 		atalk_print(ndo, p, length);
129*b636d99dSDavid van Moolenbroek 		break;
130*b636d99dSDavid van Moolenbroek 
131*b636d99dSDavid van Moolenbroek 	case BSD_AFNUM_IPX:
132*b636d99dSDavid van Moolenbroek 		ipx_print(ndo, p, length);
133*b636d99dSDavid van Moolenbroek 		break;
134*b636d99dSDavid van Moolenbroek 
135*b636d99dSDavid van Moolenbroek 	default:
136*b636d99dSDavid van Moolenbroek 		/* unknown AF_ value */
137*b636d99dSDavid van Moolenbroek 		if (!ndo->ndo_eflag)
138*b636d99dSDavid van Moolenbroek 			null_hdr_print(ndo, family, length + NULL_HDRLEN);
139*b636d99dSDavid van Moolenbroek 		if (!ndo->ndo_suppress_default_print)
140*b636d99dSDavid van Moolenbroek 			ND_DEFAULTPRINT(p, caplen);
141*b636d99dSDavid van Moolenbroek 	}
142*b636d99dSDavid van Moolenbroek 
143*b636d99dSDavid van Moolenbroek 	return (NULL_HDRLEN);
144*b636d99dSDavid van Moolenbroek }
145*b636d99dSDavid van Moolenbroek 
146*b636d99dSDavid van Moolenbroek /*
147*b636d99dSDavid van Moolenbroek  * Local Variables:
148*b636d99dSDavid van Moolenbroek  * c-style: whitesmith
149*b636d99dSDavid van Moolenbroek  * c-basic-offset: 8
150*b636d99dSDavid van Moolenbroek  * End:
151*b636d99dSDavid van Moolenbroek  */
152