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#define NETDISSECT_REWORKED
17#ifdef HAVE_CONFIG_H
18#include "config.h"
19#endif
20
21#include <tcpdump-stdinc.h>
22
23#include "interface.h"
24#include "extract.h"
25
26/*
27 * VXLAN header, RFC7348
28 *               Virtual eXtensible Local Area Network (VXLAN): A Framework
29 *               for Overlaying Virtualized Layer 2 Networks over Layer 3 Networks
30 *
31 *     0                   1                   2                   3
32 *     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
33 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
34 *    |R|R|R|R|I|R|R|R|            Reserved                           |
35 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
36 *    |                VXLAN Network Identifier (VNI) |   Reserved    |
37 *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
38 */
39
40void
41vxlan_print(netdissect_options *ndo, const u_char *bp, u_int len)
42{
43    uint8_t flags;
44    uint32_t vni;
45
46    if (len < 8) {
47        ND_PRINT((ndo, "[|VXLAN]"));
48        return;
49    }
50
51    flags = *bp;
52    bp += 4;
53
54    vni = EXTRACT_24BITS(bp);
55    bp += 4;
56
57    ND_PRINT((ndo, "VXLAN, "));
58    ND_PRINT((ndo, "flags [%s] (0x%02x), ", flags & 0x08 ? "I" : ".", flags));
59    ND_PRINT((ndo, "vni %u\n", vni));
60
61    ether_print(ndo, bp, len - 8, len - 8, NULL, NULL);
62}
63