xref: /netbsd-src/external/bsd/tcpdump/dist/print-ipfc.c (revision ccd9df534e375a4366c5b55f23782053c7a98d82)
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 #include <sys/cdefs.h>
23 #ifndef lint
24 __RCSID("$NetBSD: print-ipfc.c,v 1.7 2023/08/17 20:19:40 christos Exp $");
25 #endif
26 
27 /* \summary: IP over Fibre Channel printer */
28 
29 /* specification: RFC 2625 */
30 
31 #ifdef HAVE_CONFIG_H
32 #include <config.h>
33 #endif
34 
35 #include "netdissect-stdinc.h"
36 
37 #include <string.h>
38 
39 #define ND_LONGJMP_FROM_TCHECK
40 #include "netdissect.h"
41 #include "addrtoname.h"
42 
43 
44 struct ipfc_header {
45 	nd_byte ipfc_dhost[2+MAC_ADDR_LEN];
46 	nd_byte ipfc_shost[2+MAC_ADDR_LEN];
47 };
48 
49 #define IPFC_HDRLEN 16
50 
51 /* Extract src, dst addresses */
52 static void
53 extract_ipfc_addrs(const struct ipfc_header *ipfcp, char *ipfcsrc,
54 		   char *ipfcdst)
55 {
56 	/*
57 	 * We assume that, as per RFC 2625, the lower 48 bits of the
58 	 * source and destination addresses are MAC addresses.
59 	 */
60 	memcpy(ipfcdst, (const char *)&ipfcp->ipfc_dhost[2], MAC_ADDR_LEN);
61 	memcpy(ipfcsrc, (const char *)&ipfcp->ipfc_shost[2], MAC_ADDR_LEN);
62 }
63 
64 /*
65  * Print the Network_Header
66  */
67 static void
68 ipfc_hdr_print(netdissect_options *ndo,
69 	       const struct ipfc_header *ipfcp _U_, u_int length,
70 	       const u_char *ipfcsrc, const u_char *ipfcdst)
71 {
72 	const char *srcname, *dstname;
73 
74 	srcname = etheraddr_string(ndo, ipfcsrc);
75 	dstname = etheraddr_string(ndo, ipfcdst);
76 
77 	/*
78 	 * XXX - should we show the upper 16 bits of the addresses?
79 	 * Do so only if "vflag" is set?
80 	 * Section 3.3 "FC Port and Node Network Addresses" says that
81 	 *
82 	 *    In this specification, both the Source and Destination
83 	 *    4-bit NAA identifiers SHALL be set to binary '0001'
84 	 *    indicating that an IEEE 48-bit MAC address is contained
85 	 *    in the lower 48 bits of the network address fields. The
86 	 *    high order 12 bits in the network address fields SHALL
87 	 *    be set to 0x0000.
88 	 *
89 	 * so, for captures following this specification, the upper 16
90 	 * bits should be 0x1000, followed by a MAC address.
91 	 */
92 	ND_PRINT("%s > %s, length %u: ", srcname, dstname, length);
93 }
94 
95 static u_int
96 ipfc_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen)
97 {
98 	const struct ipfc_header *ipfcp = (const struct ipfc_header *)p;
99 	nd_mac_addr srcmac, dstmac;
100 	struct lladdr_info src, dst;
101 	int llc_hdrlen;
102 
103 	ndo->ndo_protocol = "ipfc";
104 	ND_TCHECK_LEN(p, IPFC_HDRLEN);
105 	/*
106 	 * Get the network addresses into a canonical form
107 	 */
108 	extract_ipfc_addrs(ipfcp, (char *)srcmac, (char *)dstmac);
109 
110 	if (ndo->ndo_eflag)
111 		ipfc_hdr_print(ndo, ipfcp, length, srcmac, dstmac);
112 
113 	src.addr = srcmac;
114 	src.addr_string = etheraddr_string;
115 	dst.addr = dstmac;
116 	dst.addr_string = etheraddr_string;
117 
118 	/* Skip over Network_Header */
119 	length -= IPFC_HDRLEN;
120 	p += IPFC_HDRLEN;
121 	caplen -= IPFC_HDRLEN;
122 
123 	/* Try to print the LLC-layer header & higher layers */
124 	llc_hdrlen = llc_print(ndo, p, length, caplen, &src, &dst);
125 	if (llc_hdrlen < 0) {
126 		/*
127 		 * Some kinds of LLC packet we cannot
128 		 * handle intelligently
129 		 */
130 		if (!ndo->ndo_suppress_default_print)
131 			ND_DEFAULTPRINT(p, caplen);
132 		llc_hdrlen = -llc_hdrlen;
133 	}
134 	return (IPFC_HDRLEN + llc_hdrlen);
135 }
136 
137 /*
138  * This is the top level routine of the printer.  'p' points
139  * to the Network_Header of the packet, 'h->ts' is the timestamp,
140  * 'h->len' is the length of the packet off the wire, and 'h->caplen'
141  * is the number of bytes actually captured.
142  */
143 void
144 ipfc_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, const u_char *p)
145 {
146 	ndo->ndo_protocol = "ipfc";
147 	ndo->ndo_ll_hdr_len += ipfc_print(ndo, p, h->len, h->caplen);
148 }
149