+++ /dev/null
-/*
- * Copyright (c) 2000-2008 Apple Inc. All rights reserved.
- *
- * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
- *
- * This file contains Original Code and/or Modifications of Original Code
- * as defined in and that are subject to the Apple Public Source License
- * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. The rights granted to you under the License
- * may not be used to create, or enable the creation or redistribution of,
- * unlawful or unlicensed copies of an Apple operating system, or to
- * circumvent, violate, or enable the circumvention or violation of, any
- * terms of an Apple operating system software license agreement.
- *
- * Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this file.
- *
- * The Original Code and all software distributed under the License are
- * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- * Please see the License for the specific language governing rights and
- * limitations under the License.
- *
- * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
- */
-/*-
- * Copyright (c) 1998 The NetBSD Foundation, Inc.
- * All rights reserved.
- *
- * This code is derived from software contributed to The NetBSD Foundation
- * by the 3am Software Foundry ("3am"). It was developed by Matt Thomas.
- *
- * 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.
- * 3. All advertising materials mentioning features or use of this software
- * must display the following acknowledgement:
- * This product includes software developed by the NetBSD
- * Foundation, Inc. and its contributors.
- * 4. Neither the name of The NetBSD Foundation nor the names of its
- * contributors may be used to endorse or promote products derived
- * from this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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/netinet/ip_flow.c,v 1.9.2.1 2001/08/08 08:20:35 ru Exp $
- */
-
-#include <sys/param.h>
-#include <sys/systm.h>
-#include <sys/malloc.h>
-#include <sys/mbuf.h>
-#include <sys/protosw.h>
-#include <sys/socket.h>
-#include <sys/kernel.h>
-
-#include <sys/sysctl.h>
-#include <libkern/OSAtomic.h>
-
-#include <net/if.h>
-#include <net/route.h>
-
-#include <netinet/in.h>
-#include <netinet/in_systm.h>
-#include <netinet/ip.h>
-#include <netinet/in_var.h>
-#include <netinet/ip_var.h>
-#include <netinet/ip_flow.h>
-#include <net/dlil.h>
-
-#if IPFLOW
-
-#define IPFLOW_TIMER (5 * PR_SLOWHZ)
-#define IPFLOW_HASHBITS 6 /* should not be a multiple of 8 */
-#define IPFLOW_HASHSIZE (1 << IPFLOW_HASHBITS)
-static LIST_HEAD(ipflowhead, ipflow) ipflows[IPFLOW_HASHSIZE];
-static int ipflow_inuse;
-#define IPFLOW_MAX 256
-
-#ifdef __APPLE__
-#define M_IPFLOW M_TEMP
-#endif
-
-static int ipflow_active = 0;
-SYSCTL_INT(_net_inet_ip, IPCTL_FASTFORWARDING, fastforwarding, CTLFLAG_RW,
- &ipflow_active, 0, "Enable flow-based IP forwarding");
-
-#ifndef __APPLE__
-static MALLOC_DEFINE(M_IPFLOW, "ip_flow", "IP flow");
-#endif
-
-static unsigned
-ipflow_hash(
- struct in_addr dst,
- struct in_addr src,
- unsigned tos)
-{
- unsigned hash = tos;
- int idx;
- for (idx = 0; idx < 32; idx += IPFLOW_HASHBITS)
- hash += (dst.s_addr >> (32 - idx)) + (src.s_addr >> idx);
- return hash & (IPFLOW_HASHSIZE-1);
-}
-
-static struct ipflow *
-ipflow_lookup(
- const struct ip *ip)
-{
- unsigned hash;
- struct ipflow *ipf;
-
- hash = ipflow_hash(ip->ip_dst, ip->ip_src, ip->ip_tos);
-
- ipf = LIST_FIRST(&ipflows[hash]);
- while (ipf != NULL) {
- if (ip->ip_dst.s_addr == ipf->ipf_dst.s_addr
- && ip->ip_src.s_addr == ipf->ipf_src.s_addr
- && ip->ip_tos == ipf->ipf_tos)
- break;
- ipf = LIST_NEXT(ipf, ipf_next);
- }
- return ipf;
-}
-
-int
-ipflow_fastforward(
- struct mbuf *m)
-{
- struct ip *ip;
- struct ipflow *ipf;
- struct rtentry *rt;
- struct sockaddr *dst;
- int error;
-
- /*
- * Are we forwarding packets? Big enough for an IP packet?
- */
- if (!ipforwarding || !ipflow_active || m->m_len < sizeof(struct ip))
- return 0;
- /*
- * IP header with no option and valid version and length
- */
- ip = mtod(m, struct ip *);
- if (ip->ip_v != IPVERSION || ip->ip_hl != (sizeof(struct ip) >> 2)
- || ntohs(ip->ip_len) > m->m_pkthdr.len)
- return 0;
- /*
- * Find a flow.
- */
- if ((ipf = ipflow_lookup(ip)) == NULL)
- return 0;
-
- /*
- * Route and interface still up?
- */
- rt = ipf->ipf_ro.ro_rt;
- if ((rt->rt_flags & RTF_UP) == 0 || (rt->rt_ifp->if_flags & IFF_UP) == 0)
- return 0;
-
- /*
- * Packet size OK? TTL?
- */
- if (m->m_pkthdr.len > rt->rt_ifp->if_mtu || ip->ip_ttl <= IPTTLDEC)
- return 0;
-
- /*
- * Everything checks out and so we can forward this packet.
- * Modify the TTL and incrementally change the checksum.
- */
- ip->ip_ttl -= IPTTLDEC;
- if (ip->ip_sum >= htons(0xffff - (IPTTLDEC << 8))) {
- ip->ip_sum += htons(IPTTLDEC << 8) + 1;
- } else {
- ip->ip_sum += htons(IPTTLDEC << 8);
- }
-
- /*
- * Send the packet on its way. All we can get back is ENOBUFS
- */
- ipf->ipf_uses++;
- ipf->ipf_timer = IPFLOW_TIMER;
-
- if (rt->rt_flags & RTF_GATEWAY)
- dst = rt->rt_gateway;
- else
- dst = &ipf->ipf_ro.ro_dst;
-#ifdef __APPLE__
- /* Not sure the rt_dlt is valid here !! XXX */
- if ((error = dlil_output(rt->rt_ifp, PF_INET, m, (caddr_t) rt, dst, 0)) != 0) {
-
-#else
- if ((error = (*rt->rt_ifp->if_output)(rt->rt_ifp, m, dst, rt)) != 0) {
-#endif
- if (error == ENOBUFS)
- ipf->ipf_dropped++;
- else
- ipf->ipf_errors++;
- }
- return 1;
-}
-\f
-static void
-ipflow_addstats(
- struct ipflow *ipf)
-{
- ipf->ipf_ro.ro_rt->rt_use += ipf->ipf_uses;
- OSAddAtomic(ipf->ipf_errors + ipf->ipf_dropped, &ipstat.ips_cantforward);
- OSAddAtomic(ipf->ipf_uses, &ipstat.ips_forward);
- OSAddAtomic(ipf->ipf_uses, &ipstat.ips_fastforward);
-}
-
-static void
-ipflow_free(
- struct ipflow *ipf)
-{
- /*
- * Remove the flow from the hash table (at elevated IPL).
- * Once it's off the list, we can deal with it at normal
- * network IPL.
- */
- LIST_REMOVE(ipf, ipf_next);
- ipflow_addstats(ipf);
- rtfree(ipf->ipf_ro.ro_rt);
- ipflow_inuse--;
- FREE(ipf, M_IPFLOW);
-}
-
-static struct ipflow *
-ipflow_reap(
- void)
-{
- struct ipflow *ipf, *maybe_ipf = NULL;
- int idx;
-
- for (idx = 0; idx < IPFLOW_HASHSIZE; idx++) {
- ipf = LIST_FIRST(&ipflows[idx]);
- while (ipf != NULL) {
- /*
- * If this no longer points to a valid route
- * reclaim it.
- */
- if ((ipf->ipf_ro.ro_rt->rt_flags & RTF_UP) == 0)
- goto done;
- /*
- * choose the one that's been least recently used
- * or has had the least uses in the last 1.5
- * intervals.
- */
- if (maybe_ipf == NULL
- || ipf->ipf_timer < maybe_ipf->ipf_timer
- || (ipf->ipf_timer == maybe_ipf->ipf_timer
- && ipf->ipf_last_uses + ipf->ipf_uses <
- maybe_ipf->ipf_last_uses +
- maybe_ipf->ipf_uses))
- maybe_ipf = ipf;
- ipf = LIST_NEXT(ipf, ipf_next);
- }
- }
- ipf = maybe_ipf;
- done:
- /*
- * Remove the entry from the flow table.
- */
- LIST_REMOVE(ipf, ipf_next);
- ipflow_addstats(ipf);
- rtfree(ipf->ipf_ro.ro_rt);
- return ipf;
-}
-/* note: called under the ip_mutex lock */
-void
-ipflow_slowtimo(
- void)
-{
- struct ipflow *ipf;
- int idx;
-
- for (idx = 0; idx < IPFLOW_HASHSIZE; idx++) {
- ipf = LIST_FIRST(&ipflows[idx]);
- while (ipf != NULL) {
- struct ipflow *next_ipf = LIST_NEXT(ipf, ipf_next);
- if (--ipf->ipf_timer == 0) {
- ipflow_free(ipf);
- } else {
- ipf->ipf_last_uses = ipf->ipf_uses;
- ipf->ipf_ro.ro_rt->rt_use += ipf->ipf_uses;
- OSAddAtomic(ipf->ipf_uses, &ipstat.ips_forward);
- OSAddAtomic(ipf->ipf_uses, &ipstat.ips_fastforward);
- ipstat.ips_forward += ipf->ipf_uses;
- ipstat.ips_fastforward += ipf->ipf_uses;
- ipf->ipf_uses = 0;
- }
- ipf = next_ipf;
- }
- }
-}
-
-void
-ipflow_create(
- const struct route *ro,
- struct mbuf *m)
-{
- const struct ip *const ip = mtod(m, struct ip *);
- struct ipflow *ipf;
- unsigned hash;
-
- /*
- * Don't create cache entries for ICMP messages.
- */
- if (!ipflow_active || ip->ip_p == IPPROTO_ICMP)
- return;
- /*
- * See if an existing flow struct exists. If so remove it from it's
- * list and free the old route. If not, try to malloc a new one
- * (if we aren't at our limit).
- */
- ipf = ipflow_lookup(ip);
- if (ipf == NULL) {
- if (ipflow_inuse == IPFLOW_MAX) {
- ipf = ipflow_reap();
- } else {
- ipf = (struct ipflow *) _MALLOC(sizeof(*ipf), M_IPFLOW,
- M_NOWAIT);
- if (ipf == NULL)
- return;
- ipflow_inuse++;
- }
- bzero((caddr_t) ipf, sizeof(*ipf));
- } else {
- LIST_REMOVE(ipf, ipf_next);
- ipflow_addstats(ipf);
- rtfree(ipf->ipf_ro.ro_rt);
- ipf->ipf_uses = ipf->ipf_last_uses = 0;
- ipf->ipf_errors = ipf->ipf_dropped = 0;
- }
-
- /*
- * Fill in the updated information.
- */
- ipf->ipf_ro = *ro;
- RT_ADDREF(ro->ro_rt);
- ipf->ipf_dst = ip->ip_dst;
- ipf->ipf_src = ip->ip_src;
- ipf->ipf_tos = ip->ip_tos;
- ipf->ipf_timer = IPFLOW_TIMER;
- /*
- * Insert into the approriate bucket of the flow table.
- */
- hash = ipflow_hash(ip->ip_dst, ip->ip_src, ip->ip_tos);
- LIST_INSERT_HEAD(&ipflows[hash], ipf, ipf_next);
-}
-#else /* !IPFLOW */
-int
-ipflow_fastforward(struct mbuf *m)
-{
-#pragma unused(m)
- /*
- * Since this symbol is exported (albeit unsupported), just return
- * false to keep things (e.g. PPP) happy, in case ipflow is not
- * compiled in.
- */
- return (0);
-}
-#endif /* !IPFLOW */
projects / apple / xnu.git / blobdiff