xref: /freebsd-src/contrib/tcpdump/print-vxlan.c (revision 0a7e5f1f02aad2ff5fff1c60f44c6975fd07e1d9)
1d03c0883SXin LI /*
2d03c0883SXin LI  * Redistribution and use in source and binary forms, with or without
3d03c0883SXin LI  * modification, are permitted provided that: (1) source code
4d03c0883SXin LI  * distributions retain the above copyright notice and this paragraph
5d03c0883SXin LI  * in its entirety, and (2) distributions including binary code include
6d03c0883SXin LI  * the above copyright notice and this paragraph in its entirety in
7d03c0883SXin LI  * the documentation or other materials provided with the distribution.
8d03c0883SXin LI  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND
9d03c0883SXin LI  * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
10d03c0883SXin LI  * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
11d03c0883SXin LI  * FOR A PARTICULAR PURPOSE.
12d03c0883SXin LI  *
13d03c0883SXin LI  * Original code by Francesco Fondelli (francesco dot fondelli, gmail dot com)
14d03c0883SXin LI  */
15d03c0883SXin LI 
163340d773SGleb Smirnoff /* \summary: Virtual eXtensible Local Area Network (VXLAN) printer */
173340d773SGleb Smirnoff 
183340d773SGleb Smirnoff /* specification: RFC 7348 */
193340d773SGleb Smirnoff 
20*ee67461eSJoseph Mingrone #include <config.h>
21d03c0883SXin LI 
22*ee67461eSJoseph Mingrone #include "netdissect-stdinc.h"
23d03c0883SXin LI 
24*ee67461eSJoseph Mingrone #define ND_LONGJMP_FROM_TCHECK
253340d773SGleb Smirnoff #include "netdissect.h"
26d03c0883SXin LI #include "extract.h"
27d03c0883SXin LI 
28*ee67461eSJoseph Mingrone static const struct tok vxlan_flags [] = {
29*ee67461eSJoseph Mingrone     { 0x08, "I" },
30*ee67461eSJoseph Mingrone     { 0, NULL }
31*ee67461eSJoseph Mingrone };
323340d773SGleb Smirnoff #define VXLAN_HDR_LEN 8
333340d773SGleb Smirnoff 
34d03c0883SXin LI /*
358bdc5a62SPatrick Kelsey  * VXLAN header, RFC7348
368bdc5a62SPatrick Kelsey  *               Virtual eXtensible Local Area Network (VXLAN): A Framework
378bdc5a62SPatrick Kelsey  *               for Overlaying Virtualized Layer 2 Networks over Layer 3 Networks
38d03c0883SXin LI  *
39d03c0883SXin LI  *     0                   1                   2                   3
40d03c0883SXin LI  *     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
41d03c0883SXin LI  *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
42d03c0883SXin LI  *    |R|R|R|R|I|R|R|R|            Reserved                           |
43d03c0883SXin LI  *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
44d03c0883SXin LI  *    |                VXLAN Network Identifier (VNI) |   Reserved    |
45d03c0883SXin LI  *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
46d03c0883SXin LI  */
47d03c0883SXin LI 
48d03c0883SXin LI void
493c602fabSXin LI vxlan_print(netdissect_options *ndo, const u_char *bp, u_int len)
50d03c0883SXin LI {
513c602fabSXin LI     uint8_t flags;
523c602fabSXin LI     uint32_t vni;
53d03c0883SXin LI 
54*ee67461eSJoseph Mingrone     ndo->ndo_protocol = "vxlan";
55*ee67461eSJoseph Mingrone     nd_print_protocol_caps(ndo);
563340d773SGleb Smirnoff     if (len < VXLAN_HDR_LEN)
57*ee67461eSJoseph Mingrone         goto invalid;
583340d773SGleb Smirnoff 
59*ee67461eSJoseph Mingrone     flags = GET_U_1(bp);
60*ee67461eSJoseph Mingrone     bp += 1;
61*ee67461eSJoseph Mingrone     ND_PRINT(", flags [%s] (0x%02x), ",
62*ee67461eSJoseph Mingrone              bittok2str_nosep(vxlan_flags, "invalid", flags), flags);
63d03c0883SXin LI 
64*ee67461eSJoseph Mingrone     /* 1st Reserved */
65*ee67461eSJoseph Mingrone     bp += 3;
66d03c0883SXin LI 
67*ee67461eSJoseph Mingrone     vni = GET_BE_U_3(bp);
68*ee67461eSJoseph Mingrone     bp += 3;
69*ee67461eSJoseph Mingrone     ND_PRINT("vni %u\n", vni);
70d03c0883SXin LI 
71*ee67461eSJoseph Mingrone     /* 2nd Reserved */
72*ee67461eSJoseph Mingrone     ND_TCHECK_1(bp);
73*ee67461eSJoseph Mingrone     bp += 1;
74d03c0883SXin LI 
75*ee67461eSJoseph Mingrone     ether_print(ndo, bp, len - VXLAN_HDR_LEN, ND_BYTES_AVAILABLE_AFTER(bp), NULL, NULL);
763340d773SGleb Smirnoff 
773340d773SGleb Smirnoff     return;
783340d773SGleb Smirnoff 
79*ee67461eSJoseph Mingrone invalid:
80*ee67461eSJoseph Mingrone     nd_print_invalid(ndo);
81d03c0883SXin LI }
82