freebsd-skq/contrib/tcpdump/print-openflow.c
delphij f49c5d523a MFV r276761: tcpdump 4.6.2.
MFC after:	1 month
2015-01-07 19:55:18 +00:00

120 lines
3.9 KiB
C

/*
* This module implements printing of the very basic (version-independent)
* OpenFlow header and iteration over OpenFlow messages. It is intended for
* dispatching of version-specific OpenFlow message decoding.
*
*
* Copyright (c) 2013 The TCPDUMP project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#define NETDISSECT_REWORKED
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <tcpdump-stdinc.h>
#include "interface.h"
#include "extract.h"
#include "openflow.h"
static const char tstr[] = " [|openflow]";
static const char cstr[] = " (corrupt)";
#define OF_VER_1_0 0x01
static void
of_header_print(netdissect_options *ndo, const uint8_t version, const uint8_t type,
const uint16_t length, const uint32_t xid) {
ND_PRINT((ndo, "\n\tversion unknown (0x%02x), type 0x%02x, length %u, xid 0x%08x",
version, type, length, xid));
}
/* Print a single OpenFlow message. */
static const u_char *
of_header_body_print(netdissect_options *ndo, const u_char *cp, const u_char *ep) {
uint8_t version, type;
uint16_t length;
uint32_t xid;
if (ep < cp + OF_HEADER_LEN)
goto corrupt;
/* version */
ND_TCHECK2(*cp, 1);
version = *cp;
cp += 1;
/* type */
ND_TCHECK2(*cp, 1);
type = *cp;
cp += 1;
/* length */
ND_TCHECK2(*cp, 2);
length = EXTRACT_16BITS(cp);
cp += 2;
/* xid */
ND_TCHECK2(*cp, 4);
xid = EXTRACT_32BITS(cp);
cp += 4;
/* Message length includes the header length and a message always includes
* the basic header. A message length underrun fails decoding of the rest of
* the current packet. At the same time, try decoding as much of the current
* message as possible even when it does not end within the current TCP
* segment. */
if (length < OF_HEADER_LEN) {
of_header_print(ndo, version, type, length, xid);
goto corrupt;
}
/* Decode known protocol versions further without printing the header (the
* type decoding is version-specific. */
switch (version) {
case OF_VER_1_0:
return of10_header_body_print(ndo, cp, ep, type, length, xid);
default:
of_header_print(ndo, version, type, length, xid);
ND_TCHECK2(*cp, length - OF_HEADER_LEN);
return cp + length - OF_HEADER_LEN; /* done with current message */
}
corrupt: /* fail current packet */
ND_PRINT((ndo, "%s", cstr));
ND_TCHECK2(*cp, ep - cp);
return ep;
trunc:
ND_PRINT((ndo, "%s", tstr));
return ep;
}
/* Print a TCP segment worth of OpenFlow messages presuming the segment begins
* on a message boundary. */
void
openflow_print(netdissect_options *ndo, const u_char *cp, const u_int len) {
const u_char *ep = cp + len;
ND_PRINT((ndo, ": OpenFlow"));
while (cp < ep)
cp = of_header_body_print(ndo, cp, ep);
}