/* * Copyright (c) 2000 Paycounter, Inc. * Author: Alfred Perlstein , * 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: src/sys/kern/uipc_accf.c,v 1.2.2.2 2000/09/20 21:19:21 ps Exp $ */ #define ACCEPT_FILTER_MOD #include "opt_param.h" #include #include #include #include #include #include #include #include #include #include #include #include #include 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; kfree(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 error; switch (event) { case MOD_LOAD: p = kmalloc(sizeof(*p), M_ACCF, M_WAITOK); bcopy(accfp, p, sizeof(*p)); crit_enter(); error = accept_filt_add(p); crit_exit(); 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) { crit_enter(); error = accept_filt_del(accfp->accf_name); crit_exit(); } else error = EOPNOTSUPP; break; case MOD_SHUTDOWN: error = 0; break; default: error = EOPNOTSUPP; break; } return (error); }