tcpdump/print-loopback.c
Francois-Xavier Le Bail b38f324af9 Add a summary comment in all other printers
Moreover:
Remove some redundant comments
Update some summary comments
Update the specification URL for ATA over Ethernet (AoE) protocol
2016-08-15 22:42:38 +02:00

137 lines
3.6 KiB
C

/*
* Copyright (c) 2014 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.
*/
/* \summary: Loopback Protocol printer */
/*
* originally defined as the Ethernet Configuration Testing Protocol.
* specification: http://www.mit.edu/people/jhawk/ctp.pdf
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <netdissect-stdinc.h>
#include "netdissect.h"
#include "extract.h"
#include "ether.h"
#include "addrtoname.h"
static const char tstr[] = " [|loopback]";
#define LOOPBACK_REPLY 1
#define LOOPBACK_FWDDATA 2
static const struct tok fcode_str[] = {
{ LOOPBACK_REPLY, "Reply" },
{ LOOPBACK_FWDDATA, "Forward Data" },
{ 0, NULL }
};
static void
loopback_message_print(netdissect_options *ndo, const u_char *cp, const u_int len)
{
const u_char *ep = cp + len;
uint16_t function;
if (len < 2)
goto invalid;
/* function */
ND_TCHECK2(*cp, 2);
function = EXTRACT_LE_16BITS(cp);
cp += 2;
ND_PRINT((ndo, ", %s", tok2str(fcode_str, " invalid (%u)", function)));
switch (function) {
case LOOPBACK_REPLY:
if (len < 4)
goto invalid;
/* receipt number */
ND_TCHECK2(*cp, 2);
ND_PRINT((ndo, ", receipt number %u", EXTRACT_LE_16BITS(cp)));
cp += 2;
/* data */
ND_PRINT((ndo, ", data (%u octets)", len - 4));
ND_TCHECK2(*cp, len - 4);
break;
case LOOPBACK_FWDDATA:
if (len < 8)
goto invalid;
/* forwarding address */
ND_TCHECK2(*cp, ETHER_ADDR_LEN);
ND_PRINT((ndo, ", forwarding address %s", etheraddr_string(ndo, cp)));
cp += ETHER_ADDR_LEN;
/* data */
ND_PRINT((ndo, ", data (%u octets)", len - 8));
ND_TCHECK2(*cp, len - 8);
break;
default:
ND_TCHECK2(*cp, len - 2);
break;
}
return;
invalid:
ND_PRINT((ndo, "%s", istr));
ND_TCHECK2(*cp, ep - cp);
return;
trunc:
ND_PRINT((ndo, "%s", tstr));
}
void
loopback_print(netdissect_options *ndo, const u_char *cp, const u_int len)
{
const u_char *ep = cp + len;
uint16_t skipCount;
ND_PRINT((ndo, "Loopback"));
if (len < 2)
goto invalid;
/* skipCount */
ND_TCHECK2(*cp, 2);
skipCount = EXTRACT_LE_16BITS(cp);
cp += 2;
ND_PRINT((ndo, ", skipCount %u", skipCount));
if (skipCount % 8)
ND_PRINT((ndo, " (bogus)"));
if (skipCount > len - 2)
goto invalid;
loopback_message_print(ndo, cp + skipCount, len - 2 - skipCount);
return;
invalid:
ND_PRINT((ndo, "%s", istr));
ND_TCHECK2(*cp, ep - cp);
return;
trunc:
ND_PRINT((ndo, "%s", tstr));
}