tcpdump/print-vxlan.c
Guy Harris 07a7f33ba3 Fix some narrowing warnings on LP64/LLP64 platforms.
Add a ND_BYTES_AVAILABLE_AFTER() macro to find the number of bytes
available in the captured data, starting at the byte pointed to by the
argument.  It returns a u_int rather than a ptrdiff_t, so it'll be
32 bits on LP64 and LLP64 platforms as well as on ILP32 platforms.  Use
that macro.

Make size-of-buffer arguments size_t.

Cast some size_t and ptrdiff_t values to u_int or int.
2019-04-18 10:13:49 -07:00

75 lines
2.2 KiB
C

/*
* 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 */
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include "netdissect-stdinc.h"
#include "netdissect.h"
#include "extract.h"
#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";
if (len < VXLAN_HDR_LEN)
goto trunc;
ND_TCHECK_LEN(bp, VXLAN_HDR_LEN);
flags = GET_U_1(bp);
bp += 4;
vni = GET_BE_U_3(bp);
bp += 4;
ND_PRINT("VXLAN, ");
ND_PRINT("flags [%s] (0x%02x), ", flags & 0x08 ? "I" : ".", flags);
ND_PRINT("vni %u\n", vni);
ether_print(ndo, bp, len - VXLAN_HDR_LEN, ND_BYTES_AVAILABLE_AFTER(bp), NULL, NULL);
return;
trunc:
nd_print_trunc(ndo);
}