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/*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that: (1) source code
* distributions retain the above copyright notice and this paragraph
* in its entirety, and (2) distributions including binary code include
* the above copyright notice and this paragraph in its entirety in
* the documentation or other materials provided with the distribution.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND
* WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
* LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE.
*
* Original code by Francesco Fondelli (francesco dot fondelli, gmail dot com)
*/
/* \summary: Virtual eXtensible Local Area Network (VXLAN) printer */
/* specification: RFC 7348 */
#include <config.h>
#include "netdissect-stdinc.h"
#define ND_LONGJMP_FROM_TCHECK
#include "netdissect.h"
#include "extract.h"
static const struct tok vxlan_flags [] = {
{ 0x08, "I" },
{ 0, NULL }
};
#define VXLAN_HDR_LEN 8
/*
* VXLAN header, RFC7348
* Virtual eXtensible Local Area Network (VXLAN): A Framework
* for Overlaying Virtualized Layer 2 Networks over Layer 3 Networks
*
* 0 1 2 3
* 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
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* |R|R|R|R|I|R|R|R| Reserved |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
* | VXLAN Network Identifier (VNI) | Reserved |
* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/
void
vxlan_print(netdissect_options *ndo, const u_char *bp, u_int len)
{
uint8_t flags;
uint32_t vni;
ndo->ndo_protocol = "vxlan";
nd_print_protocol_caps(ndo);
if (len < VXLAN_HDR_LEN)
goto invalid;
flags = GET_U_1(bp);
bp += 1;
ND_PRINT(", flags [%s] (0x%02x), ",
bittok2str_nosep(vxlan_flags, "invalid", flags), flags);
/* 1st Reserved */
bp += 3;
vni = GET_BE_U_3(bp);
bp += 3;
ND_PRINT("vni %u\n", vni);
/* 2nd Reserved */
ND_TCHECK_1(bp);
bp += 1;
ether_print(ndo, bp, len - VXLAN_HDR_LEN, ND_BYTES_AVAILABLE_AFTER(bp), NULL, NULL);
return;
invalid:
nd_print_invalid(ndo);
}
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