print-otv.c revision 1.2 
1/*
2 * Redistribution and use in source and binary forms, with or without
3 * modification, are permitted provided that: (1) source code
4 * distributions retain the above copyright notice and this paragraph
5 * in its entirety, and (2) distributions including binary code include
6 * the above copyright notice and this paragraph in its entirety in
7 * the documentation or other materials provided with the distribution.
8 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND
9 * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
10 * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
11 * FOR A PARTICULAR PURPOSE.
12 *
13 * Original code by Francesco Fondelli (francesco dot fondelli, gmail dot com)
14 */
15
16#include <sys/cdefs.h>
17#ifndef lint
18__RCSID("$NetBSD: print-otv.c,v 1.2 2017/01/24 23:29:14 christos Exp $");
19#endif
20
21#ifdef HAVE_CONFIG_H
22#include "config.h"
23#endif
24
25#include <netdissect-stdinc.h>
26
27#include "netdissect.h"
28#include "extract.h"
29
30/*
31 * OTV header, draft-hasmit-otv-04
32 *
33 *     0                   1                   2                   3
34 *     0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
35 *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
36 *     |R|R|R|R|I|R|R|R|           Overlay ID                          |
37 *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
38 *     |          Instance ID                          | Reserved      |
39 *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
40 */
41
42void
43otv_print(netdissect_options *ndo, const u_char *bp, u_int len)
44{
45    uint8_t flags;
46    uint32_t overlay_id;
47    uint32_t instance_id;
48
49    if (len < 8) {
50        ND_PRINT((ndo, "[|OTV]"));
51        return;
52    }
53
54    flags = *bp;
55    bp += 1;
56
57    overlay_id = EXTRACT_24BITS(bp);
58    bp += 3;
59
60    instance_id = EXTRACT_24BITS(bp);
61    bp += 4;
62
63    ND_PRINT((ndo, "OTV, "));
64    ND_PRINT((ndo, "flags [%s] (0x%02x), ", flags & 0x08 ? "I" : ".", flags));
65    ND_PRINT((ndo, "overlay %u, ", overlay_id));
66    ND_PRINT((ndo, "instance %u\n", instance_id));
67
68    ether_print(ndo, bp, len - 8, len - 8, NULL, NULL);
69}
70