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 #include <sys/cdefs.h> 24 #ifndef lint 25 __RCSID("$NetBSD: print-cip.c,v 1.6 2017/02/05 04:05:05 spz Exp $"); 26 #endif 27 28 /* \summary: Classical-IP over ATM printer */ 29 30 #ifdef HAVE_CONFIG_H 31 #include "config.h" 32 #endif 33 34 #include <string.h> 35 36 #include <netdissect-stdinc.h> 37 38 #include "netdissect.h" 39 #include "addrtoname.h" 40 41 static const unsigned char rfcllc[] = { 42 0xaa, /* DSAP: non-ISO */ 43 0xaa, /* SSAP: non-ISO */ 44 0x03, /* Ctrl: Unnumbered Information Command PDU */ 45 0x00, /* OUI: EtherType */ 46 0x00, 47 0x00 }; 48 49 static inline void 50 cip_print(netdissect_options *ndo, u_int length) 51 { 52 /* 53 * There is no MAC-layer header, so just print the length. 54 */ 55 ND_PRINT((ndo, "%u: ", length)); 56 } 57 58 /* 59 * This is the top level routine of the printer. 'p' points 60 * to the LLC/SNAP or raw header of the packet, 'h->ts' is the timestamp, 61 * 'h->len' is the length of the packet off the wire, and 'h->caplen' 62 * is the number of bytes actually captured. 63 */ 64 u_int 65 cip_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, const u_char *p) 66 { 67 u_int caplen = h->caplen; 68 u_int length = h->len; 69 size_t cmplen; 70 int llc_hdrlen; 71 72 cmplen = sizeof(rfcllc); 73 if (cmplen > caplen) 74 cmplen = caplen; 75 if (cmplen > length) 76 cmplen = length; 77 78 if (ndo->ndo_eflag) 79 cip_print(ndo, length); 80 81 if (cmplen == 0) { 82 ND_PRINT((ndo, "[|cip]")); 83 return 0; 84 } 85 if (memcmp(rfcllc, p, cmplen) == 0) { 86 /* 87 * LLC header is present. Try to print it & higher layers. 88 */ 89 llc_hdrlen = llc_print(ndo, p, length, caplen, NULL, NULL); 90 if (llc_hdrlen < 0) { 91 /* packet type not known, print raw packet */ 92 if (!ndo->ndo_suppress_default_print) 93 ND_DEFAULTPRINT(p, caplen); 94 llc_hdrlen = -llc_hdrlen; 95 } 96 } else { 97 /* 98 * LLC header is absent; treat it as just IP. 99 */ 100 llc_hdrlen = 0; 101 ip_print(ndo, p, length); 102 } 103 104 return (llc_hdrlen); 105 } 106 107 108 /* 109 * Local Variables: 110 * c-style: whitesmith 111 * c-basic-offset: 8 112 * End: 113 */ 114