uipc_accf.c revision 65534
165534Salfred/* 265534Salfred * Copyright (c) 2000 Paycounter, Inc. 365534Salfred * Author: Alfred Perlstein <alfred@paycounter.com>, <alfred@FreeBSD.org> 461837Salfred * All rights reserved. 561837Salfred * 661837Salfred * Redistribution and use in source and binary forms, with or without 761837Salfred * modification, are permitted provided that the following conditions 861837Salfred * are met: 961837Salfred * 1. Redistributions of source code must retain the above copyright 1061837Salfred * notice, this list of conditions and the following disclaimer. 1161837Salfred * 2. Redistributions in binary form must reproduce the above copyright 1261837Salfred * notice, this list of conditions and the following disclaimer in the 1361837Salfred * documentation and/or other materials provided with the distribution. 1461837Salfred * 1561837Salfred * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 1661837Salfred * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 1761837Salfred * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 1861837Salfred * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 1961837Salfred * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 2061837Salfred * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 2161837Salfred * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 2261837Salfred * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 2361837Salfred * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 2461837Salfred * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 2561837Salfred * SUCH DAMAGE. 2661837Salfred * 2761837Salfred * $FreeBSD: head/sys/kern/uipc_accf.c 65534 2000-09-06 18:49:13Z alfred $ 2861837Salfred */ 2961837Salfred 3061837Salfred#define ACCEPT_FILTER_MOD 3161837Salfred 3261837Salfred#include "opt_param.h" 3361837Salfred#include <sys/param.h> 3461837Salfred#include <sys/systm.h> 3561837Salfred#include <sys/domain.h> 3661837Salfred#include <sys/kernel.h> 3761837Salfred#include <sys/proc.h> 3861837Salfred#include <sys/malloc.h> 3961837Salfred#include <sys/mbuf.h> 4061837Salfred#include <sys/protosw.h> 4165534Salfred#include <sys/sysctl.h> 4261837Salfred#include <sys/socket.h> 4361837Salfred#include <sys/socketvar.h> 4461837Salfred#include <sys/queue.h> 4561837Salfred 4661837Salfredstatic SLIST_HEAD(, accept_filter) accept_filtlsthd = 4761837Salfred SLIST_HEAD_INITIALIZER(&accept_filtlsthd); 4861837Salfred 4961837SalfredMALLOC_DEFINE(M_ACCF, "accf", "accept filter data"); 5061837Salfred 5165534Salfredstatic int unloadable = 0; 5265534Salfred 5365534SalfredSYSCTL_DECL(_net_inet); /* XXX: some header should do this for me */ 5465534SalfredSYSCTL_NODE(_net_inet, OID_AUTO, accf, CTLFLAG_RW, 0, "Accept filters"); 5565534SalfredSYSCTL_INT(_net_inet_accf, OID_AUTO, unloadable, CTLFLAG_RW, &unloadable, 0, 5665534Salfred "Allow unload of accept filters (not recommended)"); 5765534Salfred 5861837Salfred/* 5961837Salfred * must be passed a malloc'd structure so we don't explode if the kld 6061837Salfred * is unloaded, we leak the struct on deallocation to deal with this, 6161837Salfred * but if a filter is loaded with the same name as a leaked one we re-use 6261837Salfred * the entry. 6361837Salfred */ 6461837Salfredint 6561837Salfredaccept_filt_add(struct accept_filter *filt) 6661837Salfred{ 6761837Salfred struct accept_filter *p; 6861837Salfred 6961837Salfred SLIST_FOREACH(p, &accept_filtlsthd, accf_next) 7061837Salfred if (strcmp(p->accf_name, filt->accf_name) == 0) { 7161837Salfred if (p->accf_callback != NULL) { 7261837Salfred return (EEXIST); 7361837Salfred } else { 7461837Salfred p->accf_callback = filt->accf_callback; 7561837Salfred FREE(filt, M_ACCF); 7661837Salfred return (0); 7761837Salfred } 7861837Salfred } 7961837Salfred 8061837Salfred if (p == NULL) 8161837Salfred SLIST_INSERT_HEAD(&accept_filtlsthd, filt, accf_next); 8261837Salfred return (0); 8361837Salfred} 8461837Salfred 8561837Salfredint 8661837Salfredaccept_filt_del(char *name) 8761837Salfred{ 8861837Salfred struct accept_filter *p; 8961837Salfred 9061837Salfred p = accept_filt_get(name); 9161837Salfred if (p == NULL) 9261837Salfred return (ENOENT); 9361837Salfred 9461837Salfred p->accf_callback = NULL; 9561837Salfred return (0); 9661837Salfred} 9761837Salfred 9861837Salfredstruct accept_filter * 9961837Salfredaccept_filt_get(char *name) 10061837Salfred{ 10161837Salfred struct accept_filter *p; 10261837Salfred 10361837Salfred SLIST_FOREACH(p, &accept_filtlsthd, accf_next) 10461837Salfred if (strcmp(p->accf_name, name) == 0) 10561837Salfred return (p); 10661837Salfred 10761837Salfred return (NULL); 10861837Salfred} 10961837Salfred 11061837Salfredint 11161837Salfredaccept_filt_generic_mod_event(module_t mod, int event, void *data) 11261837Salfred{ 11361837Salfred struct accept_filter *p; 11461837Salfred struct accept_filter *accfp = (struct accept_filter *) data; 11561837Salfred int s, error; 11661837Salfred 11761837Salfred switch (event) { 11861837Salfred case MOD_LOAD: 11961837Salfred MALLOC(p, struct accept_filter *, sizeof(*p), M_ACCF, M_WAITOK); 12061837Salfred bcopy(accfp, p, sizeof(*p)); 12161837Salfred s = splnet(); 12261837Salfred error = accept_filt_add(p); 12361837Salfred splx(s); 12461837Salfred break; 12561837Salfred 12661837Salfred case MOD_UNLOAD: 12763645Salfred /* 12863645Salfred * Do not support unloading yet. we don't keep track of refcounts 12963645Salfred * and unloading an accept filter callback and then having it called 13063645Salfred * is a bad thing. A simple fix would be to track the refcount 13163645Salfred * in the struct accept_filter. 13263645Salfred */ 13365534Salfred if (unloadable != 0) { 13465534Salfred s = splnet(); 13565534Salfred error = accept_filt_del(accfp->accf_name); 13665534Salfred splx(s); 13765534Salfred } else 13865534Salfred error = EOPNOTSUPP; 13961837Salfred break; 14061837Salfred 14161837Salfred case MOD_SHUTDOWN: 14261837Salfred error = 0; 14361837Salfred break; 14461837Salfred 14561837Salfred default: 14661837Salfred error = EOPNOTSUPP; 14761837Salfred break; 14861837Salfred } 14961837Salfred 15061837Salfred return (error); 15161837Salfred} 152