1 /* 2 * Marko Kiiskila carnil@cs.tut.fi 3 * 4 * Tampere University of Technology - Telecommunications Laboratory 5 * 6 * Permission to use, copy, modify and distribute this 7 * software and its documentation is hereby granted, 8 * provided that both the copyright notice and this 9 * permission notice appear in all copies of the software, 10 * derivative works or modified versions, and any portions 11 * thereof, that both notices appear in supporting 12 * documentation, and that the use of this software is 13 * acknowledged in any publications resulting from using 14 * the software. 15 * 16 * TUT ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 17 * CONDITION AND DISCLAIMS ANY LIABILITY OF ANY KIND FOR 18 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS 19 * SOFTWARE. 20 * 21 */ 22 23 #ifndef lint 24 static const char rcsid[] _U_ = 25 "@(#) $Header: /tcpdump/master/tcpdump/print-cip.c,v 1.21.2.2 2003/11/16 08:51:15 guy Exp $ (LBL)"; 26 #endif 27 28 #ifdef HAVE_CONFIG_H 29 #include "config.h" 30 #endif 31 32 #include <string.h> 33 34 #include <tcpdump-stdinc.h> 35 36 #include <stdio.h> 37 #include <pcap.h> 38 39 #include "interface.h" 40 #include "addrtoname.h" 41 #include "ethertype.h" 42 #include "ether.h" 43 44 #define RFC1483LLC_LEN 8 45 46 static unsigned char rfcllc[] = { 47 0xaa, /* DSAP: non-ISO */ 48 0xaa, /* SSAP: non-ISO */ 49 0x03, /* Ctrl: Unnumbered Information Command PDU */ 50 0x00, /* OUI: EtherType */ 51 0x00, 52 0x00 }; 53 54 static inline void 55 cip_print(int length) 56 { 57 /* 58 * There is no MAC-layer header, so just print the length. 59 */ 60 printf("%d: ", length); 61 } 62 63 /* 64 * This is the top level routine of the printer. 'p' points 65 * to the LLC/SNAP or raw header of the packet, 'h->ts' is the timestamp, 66 * 'h->length' is the length of the packet off the wire, and 'h->caplen' 67 * is the number of bytes actually captured. 68 */ 69 u_int 70 cip_if_print(const struct pcap_pkthdr *h, const u_char *p) 71 { 72 u_int caplen = h->caplen; 73 u_int length = h->len; 74 u_short extracted_ethertype; 75 76 if (memcmp(rfcllc, p, sizeof(rfcllc))==0 && caplen < RFC1483LLC_LEN) { 77 printf("[|cip]"); 78 return (0); 79 } 80 81 if (eflag) 82 cip_print(length); 83 84 if (memcmp(rfcllc, p, sizeof(rfcllc)) == 0) { 85 /* 86 * LLC header is present. Try to print it & higher layers. 87 */ 88 if (llc_print(p, length, caplen, NULL, NULL, 89 &extracted_ethertype) == 0) { 90 /* ether_type not known, print raw packet */ 91 if (!eflag) 92 cip_print(length); 93 if (extracted_ethertype) { 94 printf("(LLC %s) ", 95 etherproto_string(htons(extracted_ethertype))); 96 } 97 if (!xflag && !qflag) 98 default_print(p, caplen); 99 } 100 } else { 101 /* 102 * LLC header is absent; treat it as just IP. 103 */ 104 ip_print(p, length); 105 } 106 107 return (0); 108 } 109