/* * 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. * * $FreeBSD$ */ #ifndef lint static const char rcsid[] _U_ = "@(#) $Header: /tcpdump/master/tcpdump/print-null.c,v 1.49.2.2 2003/11/16 08:51:36 guy Exp $ (LBL)"; #endif #ifdef HAVE_CONFIG_H #include "config.h" #endif #include #include #include #include #include "interface.h" #include "addrtoname.h" #include "ip.h" #ifdef INET6 #include "ip6.h" #endif /* * 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 /* * BSD AF_ values. * * Unfortunately, the BSDs don't all use the same value for AF_INET6, * so, because we want to be able to read captures from all of the BSDs, * we check for all of them. */ #define BSD_AF_INET 2 #define BSD_AF_NS 6 /* XEROX NS protocols */ #define BSD_AF_ISO 7 #define BSD_AF_APPLETALK 16 #define BSD_AF_IPX 23 #define BSD_AF_INET6_BSD 24 /* OpenBSD (and probably NetBSD), BSD/OS */ #define BSD_AF_INET6_FREEBSD 28 #define BSD_AF_INET6_DARWIN 30 static void null_print(u_int family, u_int length) { if (nflag) printf("AF %u ", family); else { switch (family) { case BSD_AF_INET: printf("ip "); break; #ifdef INET6 case BSD_AF_INET6_BSD: case BSD_AF_INET6_FREEBSD: case BSD_AF_INET6_DARWIN: printf("ip6 "); break; #endif case BSD_AF_NS: printf("ns "); break; case BSD_AF_ISO: printf("osi "); break; case BSD_AF_APPLETALK: printf("atalk "); break; case BSD_AF_IPX: printf("ipx "); break; default: printf("AF %u ", family); break; } } printf("%d: ", length); } /* * 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)) /* * This is the top level routine of the printer. 'p' points * to the ether header of the packet, 'h->ts' is the timestamp, * 'h->length' 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); length -= NULL_HDRLEN; caplen -= NULL_HDRLEN; p += NULL_HDRLEN; if (eflag) null_print(family, length); switch (family) { case BSD_AF_INET: ip_print(p, length); break; #ifdef INET6 case BSD_AF_INET6_BSD: case BSD_AF_INET6_FREEBSD: case BSD_AF_INET6_DARWIN: ip6_print(p, length); break; #endif case BSD_AF_ISO: isoclns_print(p, length, caplen); break; case BSD_AF_APPLETALK: atalk_print(p, length); break; case BSD_AF_IPX: ipx_print(p, length); break; default: /* unknown AF_ value */ if (!eflag) null_print(family, length + NULL_HDRLEN); if (!xflag && !qflag) default_print(p, caplen); } return (NULL_HDRLEN); }