freebsd-skq/sys/net/if_faith.c
sam 9d93fce265 Locking for updates to routing table entries. Each rtentry gets a mutex
that covers updates to the contents.  Note this is separate from holding
a reference and/or locking the routing table itself.

Other/related changes:

o rtredirect loses the final parameter by which an rtentry reference
  may be returned; this was never used and added unwarranted complexity
  for locking.
o minor style cleanups to routing code (e.g. ansi-fy function decls)
o remove the logic to bump the refcnt on the parent of cloned routes,
  we assume the parent will remain as long as the clone; doing this avoids
  a circularity in locking during delete
o convert some timeouts to MPSAFE callouts

Notes:

1. rt_mtx in struct rtentry is guarded by #ifdef _KERNEL as user-level
   applications cannot/do-no know about mutex's.  Doing this requires
   that the mutex be the last element in the structure.  A better solution
   is to introduce an externalized version of struct rtentry but this is
   a major task because of the intertwining of rtentry and other data
   structures that are visible to user applications.
2. There are known LOR's that are expected to go away with forthcoming
   work to eliminate many held references.  If not these will be resolved
   prior to release.
3. ATM changes are untested.

Sponsored by:	FreeBSD Foundation
Obtained from:	BSD/OS (partly)
2003-10-04 03:44:50 +00:00

380 lines
8.4 KiB
C

/* $KAME: if_faith.c,v 1.23 2001/12/17 13:55:29 sumikawa Exp $ */
/*
* Copyright (c) 1982, 1986, 1993
* The Regents of the University of California. 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University 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 REGENTS 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 REGENTS 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.
*
* $FreeBSD$
*/
/*
* derived from
* @(#)if_loop.c 8.1 (Berkeley) 6/10/93
* Id: if_loop.c,v 1.22 1996/06/19 16:24:10 wollman Exp
*/
/*
* Loopback interface driver for protocol testing and timing.
*/
#include "opt_inet.h"
#include "opt_inet6.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/errno.h>
#include <sys/sockio.h>
#include <sys/time.h>
#include <sys/queue.h>
#include <sys/types.h>
#include <sys/malloc.h>
#include <net/if.h>
#include <net/if_types.h>
#include <net/netisr.h>
#include <net/route.h>
#include <net/bpf.h>
#ifdef INET
#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/in_var.h>
#include <netinet/ip.h>
#endif
#ifdef INET6
#ifndef INET
#include <netinet/in.h>
#endif
#include <netinet6/in6_var.h>
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#endif
#include <net/net_osdep.h>
#define FAITHNAME "faith"
struct faith_softc {
struct ifnet sc_if; /* must be first */
LIST_ENTRY(faith_softc) sc_list;
};
static int faithioctl(struct ifnet *, u_long, caddr_t);
int faithoutput(struct ifnet *, struct mbuf *, struct sockaddr *,
struct rtentry *);
static void faithrtrequest(int, struct rtentry *, struct rt_addrinfo *);
#ifdef INET6
static int faithprefix(struct in6_addr *);
#endif
static int faithmodevent(module_t, int, void *);
static MALLOC_DEFINE(M_FAITH, FAITHNAME, "Firewall Assisted Tunnel Interface");
static LIST_HEAD(, faith_softc) faith_softc_list;
int faith_clone_create(struct if_clone *, int);
void faith_clone_destroy(struct ifnet *);
struct if_clone faith_cloner = IF_CLONE_INITIALIZER(FAITHNAME,
faith_clone_create, faith_clone_destroy, 0, IF_MAXUNIT);
#define FAITHMTU 1500
static int
faithmodevent(mod, type, data)
module_t mod;
int type;
void *data;
{
switch (type) {
case MOD_LOAD:
LIST_INIT(&faith_softc_list);
if_clone_attach(&faith_cloner);
#ifdef INET6
faithprefix_p = faithprefix;
#endif
break;
case MOD_UNLOAD:
#ifdef INET6
faithprefix_p = NULL;
#endif
if_clone_detach(&faith_cloner);
while (!LIST_EMPTY(&faith_softc_list))
faith_clone_destroy(
&LIST_FIRST(&faith_softc_list)->sc_if);
break;
}
return 0;
}
static moduledata_t faith_mod = {
"if_faith",
faithmodevent,
0
};
DECLARE_MODULE(if_faith, faith_mod, SI_SUB_PSEUDO, SI_ORDER_ANY);
MODULE_VERSION(if_faith, 1);
int
faith_clone_create(ifc, unit)
struct if_clone *ifc;
int unit;
{
struct faith_softc *sc;
sc = malloc(sizeof(struct faith_softc), M_FAITH, M_WAITOK);
bzero(sc, sizeof(struct faith_softc));
sc->sc_if.if_softc = sc;
sc->sc_if.if_name = FAITHNAME;
sc->sc_if.if_unit = unit;
sc->sc_if.if_mtu = FAITHMTU;
/* Change to BROADCAST experimentaly to announce its prefix. */
sc->sc_if.if_flags = /* IFF_LOOPBACK */ IFF_BROADCAST | IFF_MULTICAST;
sc->sc_if.if_ioctl = faithioctl;
sc->sc_if.if_output = faithoutput;
sc->sc_if.if_type = IFT_FAITH;
sc->sc_if.if_hdrlen = 0;
sc->sc_if.if_addrlen = 0;
sc->sc_if.if_snd.ifq_maxlen = ifqmaxlen;
if_attach(&sc->sc_if);
bpfattach(&sc->sc_if, DLT_NULL, sizeof(u_int));
LIST_INSERT_HEAD(&faith_softc_list, sc, sc_list);
return (0);
}
void
faith_clone_destroy(ifp)
struct ifnet *ifp;
{
struct faith_softc *sc = (void *) ifp;
LIST_REMOVE(sc, sc_list);
bpfdetach(ifp);
if_detach(ifp);
free(sc, M_FAITH);
}
int
faithoutput(ifp, m, dst, rt)
struct ifnet *ifp;
struct mbuf *m;
struct sockaddr *dst;
struct rtentry *rt;
{
int isr;
M_ASSERTPKTHDR(m);
/* BPF write needs to be handled specially */
if (dst->sa_family == AF_UNSPEC) {
dst->sa_family = *(mtod(m, int *));
m->m_len -= sizeof(int);
m->m_pkthdr.len -= sizeof(int);
m->m_data += sizeof(int);
}
if (ifp->if_bpf) {
/*
* We need to prepend the address family as
* a four byte field. Cons up a faith header
* to pacify bpf. This is safe because bpf
* will only read from the mbuf (i.e., it won't
* try to free it or keep a pointer a to it).
*/
struct mbuf m0;
u_int32_t af = dst->sa_family;
m0.m_next = m;
m0.m_len = 4;
m0.m_data = (char *)&af;
BPF_MTAP(ifp, &m0);
}
if (rt && rt->rt_flags & (RTF_REJECT|RTF_BLACKHOLE)) {
m_freem(m);
return (rt->rt_flags & RTF_BLACKHOLE ? 0 :
rt->rt_flags & RTF_HOST ? EHOSTUNREACH : ENETUNREACH);
}
ifp->if_opackets++;
ifp->if_obytes += m->m_pkthdr.len;
switch (dst->sa_family) {
#ifdef INET
case AF_INET:
isr = NETISR_IP;
break;
#endif
#ifdef INET6
case AF_INET6:
isr = NETISR_IPV6;
break;
#endif
default:
m_freem(m);
return EAFNOSUPPORT;
}
/* XXX do we need more sanity checks? */
m->m_pkthdr.rcvif = ifp;
ifp->if_ipackets++;
ifp->if_ibytes += m->m_pkthdr.len;
netisr_dispatch(isr, m);
return (0);
}
/* ARGSUSED */
static void
faithrtrequest(cmd, rt, info)
int cmd;
struct rtentry *rt;
struct rt_addrinfo *info;
{
RT_LOCK_ASSERT(rt);
if (rt) {
rt->rt_rmx.rmx_mtu = rt->rt_ifp->if_mtu; /* for ISO */
/*
* For optimal performance, the send and receive buffers
* should be at least twice the MTU plus a little more for
* overhead.
*/
rt->rt_rmx.rmx_recvpipe =
rt->rt_rmx.rmx_sendpipe = 3 * FAITHMTU;
}
}
/*
* Process an ioctl request.
*/
/* ARGSUSED */
static int
faithioctl(ifp, cmd, data)
struct ifnet *ifp;
u_long cmd;
caddr_t data;
{
struct ifaddr *ifa;
struct ifreq *ifr = (struct ifreq *)data;
int error = 0;
switch (cmd) {
case SIOCSIFADDR:
ifp->if_flags |= IFF_UP | IFF_RUNNING;
ifa = (struct ifaddr *)data;
ifa->ifa_rtrequest = faithrtrequest;
/*
* Everything else is done at a higher level.
*/
break;
case SIOCADDMULTI:
case SIOCDELMULTI:
if (ifr == 0) {
error = EAFNOSUPPORT; /* XXX */
break;
}
switch (ifr->ifr_addr.sa_family) {
#ifdef INET
case AF_INET:
break;
#endif
#ifdef INET6
case AF_INET6:
break;
#endif
default:
error = EAFNOSUPPORT;
break;
}
break;
#ifdef SIOCSIFMTU
case SIOCSIFMTU:
ifp->if_mtu = ifr->ifr_mtu;
break;
#endif
case SIOCSIFFLAGS:
break;
default:
error = EINVAL;
}
return (error);
}
#ifdef INET6
/*
* XXX could be slow
* XXX could be layer violation to call sys/net from sys/netinet6
*/
static int
faithprefix(in6)
struct in6_addr *in6;
{
struct rtentry *rt;
struct sockaddr_in6 sin6;
int ret;
if (ip6_keepfaith == 0)
return 0;
bzero(&sin6, sizeof(sin6));
sin6.sin6_family = AF_INET6;
sin6.sin6_len = sizeof(struct sockaddr_in6);
sin6.sin6_addr = *in6;
rt = rtalloc1((struct sockaddr *)&sin6, 0, 0UL);
if (rt && rt->rt_ifp && rt->rt_ifp->if_type == IFT_FAITH &&
(rt->rt_ifp->if_flags & IFF_UP) != 0)
ret = 1;
else
ret = 0;
if (rt)
RTFREE_LOCKED(rt);
return ret;
}
#endif