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      1 /*
      2  * Marko Kiiskila carnil (at) 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 1.25.2.1 2005/07/07 01:24:34 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->len' 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 (!suppress_default_print)
     98 				default_print(p, caplen);
     99 		}
    100 	} else {
    101 		/*
    102 		 * LLC header is absent; treat it as just IP.
    103 		 */
    104 		ip_print(gndo, p, length);
    105 	}
    106 
    107 	return (0);
    108 }
    109 
    110 
    111 /*
    112  * Local Variables:
    113  * c-style: whitesmith
    114  * c-basic-offset: 8
    115  * End:
    116  */
    117