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/*
* Copyright (c) 2000 Paycounter, Inc.
* Author: Alfred Perlstein <alfred@paycounter.com>, <alfred@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.
*
* $FreeBSD$
*/
#define ACCEPT_FILTER_MOD
#include "opt_param.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/domain.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/protosw.h>
#include <sys/sysctl.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/queue.h>
static SLIST_HEAD(, accept_filter) accept_filtlsthd =
SLIST_HEAD_INITIALIZER(&accept_filtlsthd);
MALLOC_DEFINE(M_ACCF, "accf", "accept filter data");
static int unloadable = 0;
SYSCTL_DECL(_net_inet); /* XXX: some header should do this for me */
SYSCTL_NODE(_net_inet, OID_AUTO, accf, CTLFLAG_RW, 0, "Accept filters");
SYSCTL_INT(_net_inet_accf, OID_AUTO, unloadable, CTLFLAG_RW, &unloadable, 0,
"Allow unload of accept filters (not recommended)");
/*
* must be passed a malloc'd structure so we don't explode if the kld
* is unloaded, we leak the struct on deallocation to deal with this,
* but if a filter is loaded with the same name as a leaked one we re-use
* the entry.
*/
int
accept_filt_add(struct accept_filter *filt)
{
struct accept_filter *p;
SLIST_FOREACH(p, &accept_filtlsthd, accf_next)
if (strcmp(p->accf_name, filt->accf_name) == 0) {
if (p->accf_callback != NULL) {
return (EEXIST);
} else {
p->accf_callback = filt->accf_callback;
FREE(filt, M_ACCF);
return (0);
}
}
if (p == NULL)
SLIST_INSERT_HEAD(&accept_filtlsthd, filt, accf_next);
return (0);
}
int
accept_filt_del(char *name)
{
struct accept_filter *p;
p = accept_filt_get(name);
if (p == NULL)
return (ENOENT);
p->accf_callback = NULL;
return (0);
}
struct accept_filter *
accept_filt_get(char *name)
{
struct accept_filter *p;
SLIST_FOREACH(p, &accept_filtlsthd, accf_next)
if (strcmp(p->accf_name, name) == 0)
return (p);
return (NULL);
}
int
accept_filt_generic_mod_event(module_t mod, int event, void *data)
{
struct accept_filter *p;
struct accept_filter *accfp = (struct accept_filter *) data;
int s, error;
switch (event) {
case MOD_LOAD:
MALLOC(p, struct accept_filter *, sizeof(*p), M_ACCF, M_WAITOK);
bcopy(accfp, p, sizeof(*p));
s = splnet();
error = accept_filt_add(p);
splx(s);
break;
case MOD_UNLOAD:
/*
* Do not support unloading yet. we don't keep track of refcounts
* and unloading an accept filter callback and then having it called
* is a bad thing. A simple fix would be to track the refcount
* in the struct accept_filter.
*/
if (unloadable != 0) {
s = splnet();
error = accept_filt_del(accfp->accf_name);
splx(s);
} else
error = EOPNOTSUPP;
break;
case MOD_SHUTDOWN:
error = 0;
break;
default:
error = EOPNOTSUPP;
break;
}
return (error);
}
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