xref: /freebsd/contrib/tcpdump/print-ipfc.c (revision dd41de95a84d979615a2ef11df6850622bf6184e)
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 #include "ether.h"
38 
39 struct ipfc_header {
40 	u_char  ipfc_dhost[8];
41 	u_char  ipfc_shost[8];
42 };
43 
44 #define IPFC_HDRLEN 16
45 
46 /* Extract src, dst addresses */
47 static inline void
48 extract_ipfc_addrs(const struct ipfc_header *ipfcp, char *ipfcsrc,
49     char *ipfcdst)
50 {
51 	/*
52 	 * We assume that, as per RFC 2625, the lower 48 bits of the
53 	 * source and destination addresses are MAC addresses.
54 	 */
55 	memcpy(ipfcdst, (const char *)&ipfcp->ipfc_dhost[2], 6);
56 	memcpy(ipfcsrc, (const char *)&ipfcp->ipfc_shost[2], 6);
57 }
58 
59 /*
60  * Print the Network_Header
61  */
62 static inline void
63 ipfc_hdr_print(netdissect_options *ndo,
64 	   register const struct ipfc_header *ipfcp _U_,
65 	   register u_int length, register const u_char *ipfcsrc,
66 	   register const u_char *ipfcdst)
67 {
68 	const char *srcname, *dstname;
69 
70 	srcname = etheraddr_string(ndo, ipfcsrc);
71 	dstname = etheraddr_string(ndo, ipfcdst);
72 
73 	/*
74 	 * XXX - should we show the upper 16 bits of the addresses?
75 	 * Do so only if "vflag" is set?
76 	 * Section 3.3 "FC Port and Node Network Addresses" says that
77 	 *
78 	 *    In this specification, both the Source and Destination
79 	 *    4-bit NAA identifiers SHALL be set to binary '0001'
80 	 *    indicating that an IEEE 48-bit MAC address is contained
81 	 *    in the lower 48 bits of the network address fields. The
82 	 *    high order 12 bits in the network address fields SHALL
83 	 *    be set to 0x0000.
84 	 *
85 	 * so, for captures following this specification, the upper 16
86 	 * bits should be 0x1000, followed by a MAC address.
87 	 */
88 	ND_PRINT((ndo, "%s > %s, length %u: ", srcname, dstname, length));
89 }
90 
91 static u_int
92 ipfc_print(netdissect_options *ndo, const u_char *p, u_int length, u_int caplen)
93 {
94 	const struct ipfc_header *ipfcp = (const struct ipfc_header *)p;
95 	struct ether_header ehdr;
96 	struct lladdr_info src, dst;
97 	int llc_hdrlen;
98 
99 	if (caplen < IPFC_HDRLEN) {
100 		ND_PRINT((ndo, "[|ipfc]"));
101 		return (caplen);
102 	}
103 	/*
104 	 * Get the network addresses into a canonical form
105 	 */
106 	extract_ipfc_addrs(ipfcp, (char *)ESRC(&ehdr), (char *)EDST(&ehdr));
107 
108 	if (ndo->ndo_eflag)
109 		ipfc_hdr_print(ndo, ipfcp, length, ESRC(&ehdr), EDST(&ehdr));
110 
111 	src.addr = ESRC(&ehdr);
112 	src.addr_string = etheraddr_string;
113 	dst.addr = EDST(&ehdr);
114 	dst.addr_string = etheraddr_string;
115 
116 	/* Skip over Network_Header */
117 	length -= IPFC_HDRLEN;
118 	p += IPFC_HDRLEN;
119 	caplen -= IPFC_HDRLEN;
120 
121 	/* Try to print the LLC-layer header & higher layers */
122 	llc_hdrlen = llc_print(ndo, p, length, caplen, &src, &dst);
123 	if (llc_hdrlen < 0) {
124 		/*
125 		 * Some kinds of LLC packet we cannot
126 		 * handle intelligently
127 		 */
128 		if (!ndo->ndo_suppress_default_print)
129 			ND_DEFAULTPRINT(p, caplen);
130 		llc_hdrlen = -llc_hdrlen;
131 	}
132 	return (IPFC_HDRLEN + llc_hdrlen);
133 }
134 
135 /*
136  * This is the top level routine of the printer.  'p' points
137  * to the Network_Header of the packet, 'h->ts' is the timestamp,
138  * 'h->len' is the length of the packet off the wire, and 'h->caplen'
139  * is the number of bytes actually captured.
140  */
141 u_int
142 ipfc_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, register const u_char *p)
143 {
144 	return (ipfc_print(ndo, p, h->len, h->caplen));
145 }
146