freebsd-dev/sys/netinet/libalias/alias_dummy.c
Pedro F. Giffuni fe267a5590 sys: general adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

No functional change intended.
2017-11-27 15:23:17 +00:00

156 lines
4.0 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2005 Paolo Pisati <piso@FreeBSD.org>
* 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 AUTHOR 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 AUTHOR 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* Alias_dummy is just an empty skeleton used to demostrate how to write
* a module for libalias, that will run unalterated in userland or in
* kernel land.
*/
#ifdef _KERNEL
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/module.h>
#else
#include <errno.h>
#include <sys/types.h>
#include <stdio.h>
#endif
#include <netinet/in_systm.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#include <netinet/udp.h>
#ifdef _KERNEL
#include <netinet/libalias/alias_local.h>
#include <netinet/libalias/alias_mod.h>
#else
#include "alias_local.h"
#include "alias_mod.h"
#endif
static void
AliasHandleDummy(struct libalias *la, struct ip *ip, struct alias_data *ah);
static int
fingerprint(struct libalias *la, struct alias_data *ah)
{
/*
* Check here all the data that will be used later, if any field
* is empy/NULL, return a -1 value.
*/
if (ah->dport == NULL || ah->sport == NULL || ah->lnk == NULL ||
ah->maxpktsize == 0)
return (-1);
/*
* Fingerprint the incoming packet, if it matches any conditions
* return an OK value.
*/
if (ntohs(*ah->dport) == 123
|| ntohs(*ah->sport) == 456)
return (0); /* I know how to handle it. */
return (-1); /* I don't recognize this packet. */
}
/*
* Wrap in this general purpose function, the real function used to alias the
* packets.
*/
static int
protohandler(struct libalias *la, struct ip *pip, struct alias_data *ah)
{
AliasHandleDummy(la, pip, ah);
return (0);
}
/*
* NOTA BENE: the next variable MUST NOT be renamed in any case if you want
* your module to work in userland, cause it's used to find and use all
* the protocol handlers present in every module.
* So WATCH OUT, your module needs this variables and it needs it with
* ITS EXACT NAME: handlers.
*/
struct proto_handler handlers [] = {
{
.pri = 666,
.dir = IN|OUT,
.proto = UDP|TCP,
.fingerprint = &fingerprint,
.protohandler = &protohandler
},
{ EOH }
};
static int
mod_handler(module_t mod, int type, void *data)
{
int error;
switch (type) {
case MOD_LOAD:
error = 0;
LibAliasAttachHandlers(handlers);
break;
case MOD_UNLOAD:
error = 0;
LibAliasDetachHandlers(handlers);
break;
default:
error = EINVAL;
}
return (error);
}
#ifdef _KERNEL
static
#endif
moduledata_t alias_mod = {
"alias_dummy", mod_handler, NULL
};
#ifdef _KERNEL
DECLARE_MODULE(alias_dummy, alias_mod, SI_SUB_DRIVERS, SI_ORDER_SECOND);
MODULE_VERSION(alias_dummy, 1);
MODULE_DEPEND(alias_dummy, libalias, 1, 1, 1);
#endif
static void
AliasHandleDummy(struct libalias *la, struct ip *ip, struct alias_data *ah)
{
; /* Dummy. */
}