The Tcpdump Group git mirrors - tcpdump/blob - print-ipfc.c

   1 /*
   2  * Copyright (c) 1991, 1992, 1993, 1994, 1995, 1996, 1997
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that: (1) source code distributions
   7  * retain the above copyright notice and this paragraph in its entirety, (2)
   8  * distributions including binary code include the above copyright notice and
   9  * this paragraph in its entirety in the documentation or other materials
  10  * provided with the distribution, and (3) all advertising materials mentioning
  11  * features or use of this software display the following acknowledgement:
  12  * ``This product includes software developed by the University of California,
  13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
  14  * the University nor the names of its contributors may be used to endorse
  15  * or promote products derived from this software without specific prior
  16  * written permission.
  17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
  18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  20  */
  21
  22 /* \summary: IP over Fibre Channel printer */
  23
  24 /* specification: RFC 2625 */
  25
  26 #ifdef HAVE_CONFIG_H
  27 #include <config.h>
  28 #endif
  29
  30 #include "netdissect-stdinc.h"
  31
  32 #include <string.h>
  33
  34 #include "netdissect.h"
  35 #include "addrtoname.h"
  36
  37
  38 struct ipfc_header {
  39         nd_byte ipfc_dhost[2+MAC_ADDR_LEN];
  40         nd_byte ipfc_shost[2+MAC_ADDR_LEN];
  41 };
  42
  43 #define IPFC_HDRLEN 16
  44
  45 /* Extract src, dst addresses */
  46 static void
  47 extract_ipfc_addrs(const struct ipfc_header *ipfcp, char *ipfcsrc,
  48                    char *ipfcdst)
  49 {
  50         /*
  51          * We assume that, as per RFC 2625, the lower 48 bits of the
  52          * source and destination addresses are MAC addresses.
  53          */
  54         memcpy(ipfcdst, (const char *)&ipfcp->ipfc_dhost[2], MAC_ADDR_LEN);
  55         memcpy(ipfcsrc, (const char *)&ipfcp->ipfc_shost[2], MAC_ADDR_LEN);
  56 }
  57
  58 /*
  59  * Print the Network_Header
  60  */
  61 static void
  62 ipfc_hdr_print(netdissect_options *ndo,
  63                const struct ipfc_header *ipfcp _U_, u_int length,
  64                const u_char *ipfcsrc, const u_char *ipfcdst)
  65 {
  66         const char *srcname, *dstname;
  67
  68         srcname = etheraddr_string(ndo, ipfcsrc);
  69         dstname = etheraddr_string(ndo, ipfcdst);
  70
  71         /*
  72          * XXX - should we show the upper 16 bits of the addresses?
  73          * Do so only if "vflag" is set?
  74          * Section 3.3 "FC Port and Node Network Addresses" says that
  75          *
  76          *    In this specification, both the Source and Destination
  77          *    4-bit NAA identifiers SHALL be set to binary '0001'
  78          *    indicating that an IEEE 48-bit MAC address is contained
  79          *    in the lower 48 bits of the network address fields. The
  80          *    high order 12 bits in the network address fields SHALL
  81          *    be set to 0x0000.
  82          *
  83          * so, for captures following this specification, the upper 16
  84          * bits should be 0x1000, followed by a MAC address.
  85          */
  86         ND_PRINT("%s > %s, length %u: ", srcname, dstname, length);
  87 }
  88
  89 static u_int
  90 ipfc_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen)
  91 {
  92         const struct ipfc_header *ipfcp = (const struct ipfc_header *)p;
  93         nd_mac_addr srcmac, dstmac;
  94         struct lladdr_info src, dst;
  95         int llc_hdrlen;
  96
  97         ndo->ndo_protocol = "ipfc";
  98         if (caplen < IPFC_HDRLEN)
  99                 goto trunc;
 100         /*
 101          * Get the network addresses into a canonical form
 102          */
 103         ND_TCHECK_SIZE(ipfcp);
 104         extract_ipfc_addrs(ipfcp, (char *)srcmac, (char *)dstmac);
 105
 106         if (ndo->ndo_eflag)
 107                 ipfc_hdr_print(ndo, ipfcp, length, srcmac, dstmac);
 108
 109         src.addr = srcmac;
 110         src.addr_string = etheraddr_string;
 111         dst.addr = dstmac;
 112         dst.addr_string = etheraddr_string;
 113
 114         /* Skip over Network_Header */
 115         length -= IPFC_HDRLEN;
 116         p += IPFC_HDRLEN;
 117         caplen -= IPFC_HDRLEN;
 118
 119         /* Try to print the LLC-layer header & higher layers */
 120         llc_hdrlen = llc_print(ndo, p, length, caplen, &src, &dst);
 121         if (llc_hdrlen < 0) {
 122                 /*
 123                  * Some kinds of LLC packet we cannot
 124                  * handle intelligently
 125                  */
 126                 if (!ndo->ndo_suppress_default_print)
 127                         ND_DEFAULTPRINT(p, caplen);
 128                 llc_hdrlen = -llc_hdrlen;
 129         }
 130         return (IPFC_HDRLEN + llc_hdrlen);
 131 trunc:
 132         nd_print_trunc(ndo);
 133         return caplen;
 134 }
 135
 136 /*
 137  * This is the top level routine of the printer.  'p' points
 138  * to the Network_Header of the packet, 'h->ts' is the timestamp,
 139  * 'h->len' is the length of the packet off the wire, and 'h->caplen'
 140  * is the number of bytes actually captured.
 141  */
 142 void
 143 ipfc_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, const u_char *p)
 144 {
 145         ndo->ndo_protocol = "ipfc";
 146         ndo->ndo_ll_hdr_len += ipfc_print(ndo, p, h->len, h->caplen);
 147 }