NetBSD/sys/netinet/if_ieee1394arp.c

673 lines
19 KiB
C

/* $NetBSD: if_ieee1394arp.c,v 1.7 2001/11/15 09:48:26 lukem Exp $ */
/*
* Copyright (c) 2000 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Atsushi Onoe.
*
* 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.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: if_ieee1394arp.c,v 1.7 2001/11/15 09:48:26 lukem Exp $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/syslog.h>
#include <sys/kernel.h>
#include <sys/mbuf.h>
#include <sys/device.h>
#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_ieee1394.h>
#include <net/if_types.h>
#include <net/if_media.h>
#include <net/ethertypes.h>
#include <net/route.h>
#include <netinet/in.h>
#include <netinet/in_var.h>
#include <netinet/if_inarp.h>
#include <netinet/if_ieee1394arp.h>
#define SIN(s) ((struct sockaddr_in *)s)
#define SDL(s) ((struct sockaddr_dl *)s)
static void ieee1394arprequest(struct ifnet *, struct in_addr *,
struct in_addr *);
static struct llinfo_arp *ieee1394arplookup(struct in_addr *, int, int);
/* XXX: timer values */
int ieee1394arpt_keep = (20*60); /* once resolved, good for 20 more minutes */
int ieee1394arpt_down = 20; /* once declared down, don't send for 20 secs */
int ieee1394arp_maxtries = 5;
#define rt_expire rt_rmx.rmx_expire
/* import from netinet/if_arp.c */
extern LIST_HEAD(, llinfo_arp) llinfo_arp;
extern int arp_inuse, arp_allocated;
extern int arp_locked;
extern int arpinit_done;
#if __NetBSD_Version__ >= 105060000
extern struct arpstat arpstat;
#else
struct arpstat {
u_quad_t as_sndtotal; /* total packets sent */
u_quad_t as_sndreply; /* replies sent */
u_quad_t as_sndrequest; /* requests sent */
u_quad_t as_rcvtotal; /* total packets received */
u_quad_t as_rcvrequest; /* valid requests received */
u_quad_t as_rcvreply; /* replies received */
u_quad_t as_rcvmcast; /* multicast/broadcast received */
u_quad_t as_rcvbadproto; /* unknown protocol type received */
u_quad_t as_rcvbadlen; /* bad (short) length received */
u_quad_t as_rcvzerotpa; /* received w/ null target ip */
u_quad_t as_rcvzerospa; /* received w/ null src ip */
u_quad_t as_rcvnoint; /* couldn't map to interface */
u_quad_t as_rcvlocalsha; /* received from local hw address */
u_quad_t as_rcvbcastsha; /* received w/ broadcast src */
u_quad_t as_rcvlocalspa; /* received for a local ip [dup!] */
u_quad_t as_rcvoverperm; /* attempts to overwrite static info */
u_quad_t as_rcvoverint; /* attempts to overwrite wrong if */
u_quad_t as_rcvover; /* entries overwritten! */
u_quad_t as_rcvlenchg; /* changes in hw add len */
u_quad_t as_dfrtotal; /* deferred pending ARP resolution. */
u_quad_t as_dfrsent; /* deferred, then sent */
u_quad_t as_dfrdropped; /* deferred, then dropped */
u_quad_t as_allocfail; /* Failures to allocate llinfo */
} arpstat;
#endif
static __inline int arp_lock_try(int);
static __inline void arp_unlock(void);
static __inline int
arp_lock_try(recurse)
int recurse;
{
int s;
/*
* Use splvm() -- we're blocking things that would cause
* mbuf allocation.
*/
s = splvm();
if (!recurse && arp_locked) {
splx(s);
return 0;
}
arp_locked++;
splx(s);
return 1;
}
static __inline void
arp_unlock()
{
int s;
s = splvm();
arp_locked--;
splx(s);
}
#define ARP_LOCK(x) (void)arp_lock_try(x)
#define ARP_UNLOCK() arp_unlock();
/*
* Parallel to llc_rtrequest.
*/
void
ieee1394arp_rtrequest(int req, struct rtentry *rt, struct rt_addrinfo *info)
{
struct sockaddr *gate = rt->rt_gateway;
struct llinfo_arp *la = (struct llinfo_arp *)rt->rt_llinfo;
static struct sockaddr_dl null_sdl =
{ sizeof(null_sdl) - sizeof(null_sdl.sdl_data) +
sizeof(struct ieee1394_hwaddr), AF_LINK };
struct mbuf *mold;
int s;
struct in_ifaddr *ia;
struct ifaddr *ifa;
if (!arpinit_done) {
/*
* Dummy call to arp_rtrequest to initialize arp timer.
*/
struct rtentry rtdummy;
rtdummy.rt_flags = RTF_GATEWAY;
arp_rtrequest(0, &rtdummy, NULL);
}
if (rt->rt_flags & RTF_GATEWAY)
return;
ARP_LOCK(1); /* we may already be locked here. */
switch (req) {
case RTM_ADD:
/*
* XXX: If this is a manually added route to interface
* such as older version of routed or gated might provide,
* restore cloning bit.
*/
if ((rt->rt_flags & RTF_HOST) == 0 &&
SIN(rt_mask(rt))->sin_addr.s_addr != 0xffffffff)
rt->rt_flags |= RTF_CLONING;
if (rt->rt_flags & RTF_CLONING) {
/*
* Case 1: This route should come from a route to iface.
*/
rt_setgate(rt, rt_key(rt),
(struct sockaddr *)&null_sdl);
gate = rt->rt_gateway;
SDL(gate)->sdl_type = rt->rt_ifp->if_type;
SDL(gate)->sdl_index = rt->rt_ifp->if_index;
/*
* Give this route an expiration time, even though
* it's a "permanent" route, so that routes cloned
* from it do not need their expiration time set.
*/
rt->rt_expire = time.tv_sec;
break;
}
/* Announce a new entry if requested. */
if (rt->rt_flags & RTF_ANNOUNCE)
ieee1394arprequest(rt->rt_ifp,
&SIN(rt_key(rt))->sin_addr,
&SIN(rt_key(rt))->sin_addr);
/*FALLTHROUGH*/
case RTM_RESOLVE:
if (gate->sa_family != AF_LINK ||
gate->sa_len < null_sdl.sdl_len) {
log(LOG_DEBUG, "ieee1394arp_rtrequest: bad gateway value\n");
break;
}
SDL(gate)->sdl_type = rt->rt_ifp->if_type;
SDL(gate)->sdl_index = rt->rt_ifp->if_index;
if (la != 0)
break; /* This happens on a route change */
/*
* Case 2: This route may come from cloning, or a manual route
* add with a LL address.
*/
la = malloc(sizeof(*la), M_RTABLE, M_DONTWAIT);
rt->rt_llinfo = (caddr_t)la;
if (la == 0) {
log(LOG_DEBUG, "ieee1394arp_rtrequest: malloc failed\n");
break;
}
arp_inuse++, arp_allocated++;
memset(la, 0, sizeof(*la));
la->la_rt = rt;
rt->rt_flags |= RTF_LLINFO;
LIST_INSERT_HEAD(&llinfo_arp, la, la_list);
INADDR_TO_IA(SIN(rt_key(rt))->sin_addr, ia);
while (ia && ia->ia_ifp != rt->rt_ifp)
NEXT_IA_WITH_SAME_ADDR(ia);
if (ia) {
/*
* This test used to be
* if (loif.if_flags & IFF_UP)
* It allowed local traffic to be forced through
* the hardware by configuring the loopback down.
* However, it causes problems during network
* configuration for boards that can't receive
* packets they send. It is now necessary to clear
* "useloopback" and remove the route to force
* traffic out to the hardware.
*
* In 4.4BSD, the above "if" statement checked
* rt->rt_ifa against rt_key(rt). It was changed
* to the current form so that we can provide a
* better support for multiple IPv4 address on a
* interface.
*/
rt->rt_expire = 0;
memcpy(LLADDR(SDL(gate)),
LLADDR(rt->rt_ifp->if_sadl),
SDL(gate)->sdl_alen = rt->rt_ifp->if_addrlen);
#if NLOOP > 0
if (useloopback)
rt->rt_ifp = &loif[0];
#endif
/*
* make sure to set rt->rt_ifa to the interface
* address we are using, otherwise we will have trouble
* with source address selection.
*/
ifa = &ia->ia_ifa;
if (ifa != rt->rt_ifa) {
IFAFREE(rt->rt_ifa);
IFAREF(ifa);
rt->rt_ifa = ifa;
}
}
break;
case RTM_DELETE:
if (la == 0)
break;
arp_inuse--;
LIST_REMOVE(la, la_list);
rt->rt_llinfo = 0;
rt->rt_flags &= ~RTF_LLINFO;
s = splnet();
mold = la->la_hold;
la->la_hold = 0;
splx(s);
if (mold)
m_freem(mold);
Free((caddr_t)la);
}
ARP_UNLOCK();
}
/*
* Broadcast an ARP request. Caller specifies:
* - ieee1394arp header source ip address
* - ieee1394arp header target ip address
*/
static void
ieee1394arprequest(struct ifnet *ifp, struct in_addr *sip, struct in_addr *tip)
{
struct mbuf *m;
struct ieee1394_arp *iar;
struct sockaddr sa;
if ((m = m_gethdr(M_DONTWAIT, MT_DATA)) == NULL)
return;
m->m_len = sizeof(*iar);
m->m_pkthdr.len = m->m_len;
MH_ALIGN(m, m->m_len);
iar = mtod(m, struct ieee1394_arp *);
memset(iar, 0, m->m_len);
iar->iar_arp.ar_hrd = htons(ARPHRD_IEEE1394);
iar->iar_arp.ar_pro = htons(ETHERTYPE_IP);
iar->iar_arp.ar_hln = sizeof(struct ieee1394_hwaddr);
iar->iar_arp.ar_pln = sizeof(struct in_addr);
iar->iar_arp.ar_op = htons(ARPOP_REQUEST);
memcpy(&iar->iar_sip, sip, sizeof(struct in_addr));
memcpy(&iar->iar_tip, tip, sizeof(struct in_addr));
memcpy(&iar->iar_sha, LLADDR(ifp->if_sadl), ifp->if_addrlen);
sa.sa_family = AF_ARP;
sa.sa_len = 2;
m->m_flags |= M_BCAST;
arpstat.as_sndtotal++;
arpstat.as_sndrequest++;
(*ifp->if_output)(ifp, m, &sa, (struct rtentry *)0);
}
/*
* Resolve an IP address into an ethernet address. If success,
* desthw is filled in. If there is no entry in ieee1394arptab,
* set one up and broadcast a request for the IP address.
* Hold onto this mbuf and resend it once the address
* is finally resolved. A return value of 1 indicates
* that desthw has been filled in and the packet should be sent
* normally; a 0 return indicates that the packet has been
* taken over here, either now or for later transmission.
*/
int
ieee1394arpresolve(struct ifnet *ifp, struct rtentry *rt, struct mbuf *m,
struct sockaddr *dst, struct ieee1394_hwaddr *desthw)
{
struct llinfo_arp *la;
struct sockaddr_dl *sdl;
struct mbuf *mold;
int s;
if (rt)
la = (struct llinfo_arp *)rt->rt_llinfo;
else {
if ((la = ieee1394arplookup(&SIN(dst)->sin_addr, 1, 0)) != NULL)
rt = la->la_rt;
}
if (la == 0 || rt == 0) {
arpstat.as_allocfail++;
log(LOG_DEBUG, "ieee1394arpresolve: can't allocate llinfo\n");
m_freem(m);
return (0);
}
sdl = SDL(rt->rt_gateway);
/*
* Check the address family and length is valid, the address
* is resolved; otherwise, try to resolve.
*/
if ((rt->rt_expire == 0 || rt->rt_expire > time.tv_sec) &&
sdl->sdl_family == AF_LINK && sdl->sdl_alen != 0) {
memcpy(desthw, LLADDR(sdl),
min(sdl->sdl_alen, ifp->if_addrlen));
return 1;
}
/*
* There is an ieee1394arptab entry, but no ethernet address
* response yet. Replace the held mbuf with this
* latest one.
*/
arpstat.as_dfrtotal++;
s = splnet();
mold = la->la_hold;
la->la_hold = m;
splx(s);
if (mold) {
arpstat.as_dfrdropped++;
m_freem(mold);
}
/*
* Re-send the ARP request when appropriate.
*/
#ifdef DIAGNOSTIC
if (rt->rt_expire == 0) {
/* This should never happen. (Should it? -gwr) */
printf("ieee1394arpresolve: unresolved and rt_expire == 0\n");
/* Set expiration time to now (expired). */
rt->rt_expire = time.tv_sec;
}
#endif
if (rt->rt_expire) {
rt->rt_flags &= ~RTF_REJECT;
if (la->la_asked == 0 || rt->rt_expire != time.tv_sec) {
rt->rt_expire = time.tv_sec;
if (la->la_asked++ < ieee1394arp_maxtries)
ieee1394arprequest(ifp,
&SIN(rt->rt_ifa->ifa_addr)->sin_addr,
&SIN(dst)->sin_addr);
else {
rt->rt_flags |= RTF_REJECT;
rt->rt_expire += ieee1394arpt_down;
la->la_asked = 0;
}
}
}
return (0);
}
void
in_ieee1394arpinput(struct mbuf *m)
{
struct ieee1394_arp *iar;
struct ifnet *ifp = m->m_pkthdr.rcvif;
struct llinfo_arp *la = 0;
struct rtentry *rt;
struct in_ifaddr *ia;
struct sockaddr_dl *sdl;
struct sockaddr sa;
struct in_addr isaddr, itaddr, myaddr;
int op;
struct mbuf *mold;
int s;
iar = mtod(m, struct ieee1394_arp *);
op = ntohs(iar->iar_arp.ar_op);
memcpy(&isaddr, &iar->iar_sip, sizeof(isaddr));
memcpy(&itaddr, &iar->iar_tip, sizeof(itaddr));
if (m->m_flags & (M_BCAST|M_MCAST))
arpstat.as_rcvmcast++;
/*
* If the target IP address is zero, ignore the packet.
* This prevents the code below from tring to answer
* when we are using IP address zero (booting).
*/
if (in_nullhost(itaddr)) {
arpstat.as_rcvzerotpa++;
goto out;
}
/*
* If the source IP address is zero, this is most likely a
* confused host trying to use IP address zero. (Windoze?)
* XXX: Should we bother trying to reply to these?
*/
if (in_nullhost(isaddr)) {
arpstat.as_rcvzerospa++;
goto out;
}
/*
* Search for a matching interface address
* or any address on the interface to use
* as a dummy address in the rest of this function
*/
INADDR_TO_IA(itaddr, ia);
while ((ia != NULL) && ia->ia_ifp != m->m_pkthdr.rcvif)
NEXT_IA_WITH_SAME_ADDR(ia);
if (ia == NULL) {
INADDR_TO_IA(isaddr, ia);
while ((ia != NULL) && ia->ia_ifp != m->m_pkthdr.rcvif)
NEXT_IA_WITH_SAME_ADDR(ia);
if (ia == NULL) {
IFP_TO_IA(ifp, ia);
if (ia == NULL) {
arpstat.as_rcvnoint++;
goto out;
}
}
}
myaddr = ia->ia_addr.sin_addr;
if (memcmp(&iar->iar_sha, LLADDR(ifp->if_sadl), ifp->if_addrlen) == 0) {
arpstat.as_rcvlocalsha++;
goto out; /* it's from me, ignore it. */
}
if (memcmp(iar->iar_sha.iha_uid, ifp->if_broadcastaddr,
IEEE1394_ADDR_LEN) == 0) {
arpstat.as_rcvbcastsha++;
log(LOG_ERR,
"%s: ieee1394arp: link address is broadcast for IP address %s!\n",
ifp->if_xname, in_fmtaddr(isaddr));
goto out;
}
if (in_hosteq(isaddr, myaddr)) {
arpstat.as_rcvlocalspa++;
log(LOG_ERR,
"duplicate IP address %s sent from link address %s\n",
in_fmtaddr(isaddr), ieee1394_sprintf(iar->iar_sha.iha_uid));
itaddr = myaddr;
goto reply;
}
la = ieee1394arplookup(&isaddr, in_hosteq(itaddr, myaddr), 0);
if (la && (rt = la->la_rt) && (sdl = SDL(rt->rt_gateway))) {
if (sdl->sdl_alen &&
memcmp(&iar->iar_sha, LLADDR(sdl), sdl->sdl_alen) != 0) {
if (rt->rt_flags & RTF_STATIC) {
arpstat.as_rcvoverperm++;
log(LOG_INFO,
"%s tried to overwrite permanent ieee1394arp info"
" for %s\n",
ieee1394_sprintf(iar->iar_sha.iha_uid),
in_fmtaddr(isaddr));
goto out;
} else if (rt->rt_ifp != ifp) {
arpstat.as_rcvoverint++;
log(LOG_INFO,
"%s on %s tried to overwrite "
"ieee1394arp info for %s on %s\n",
ieee1394_sprintf(iar->iar_sha.iha_uid),
ifp->if_xname, in_fmtaddr(isaddr),
rt->rt_ifp->if_xname);
goto out;
} else {
arpstat.as_rcvover++;
log(LOG_INFO,
"ieee1394arp info overwritten for %s by %s\n",
in_fmtaddr(isaddr),
ieee1394_sprintf(iar->iar_sha.iha_uid));
}
}
/*
* sanity check for the address length.
* XXX this does not work for protocols with variable address
* length. -is
*/
if (sdl->sdl_alen &&
sdl->sdl_alen != iar->iar_arp.ar_hln) {
arpstat.as_rcvlenchg++;
log(LOG_WARNING,
"ieee1394arp from %s: new addr len %d, was %d",
in_fmtaddr(isaddr), iar->iar_arp.ar_hln, sdl->sdl_alen);
}
if (ifp->if_addrlen != iar->iar_arp.ar_hln) {
arpstat.as_rcvbadlen++;
log(LOG_WARNING,
"ieee1394arp from %s: addr len: new %d, i/f %d (ignored)",
in_fmtaddr(isaddr), iar->iar_arp.ar_hln,
ifp->if_addrlen);
goto reply;
}
memcpy(LLADDR(sdl), &iar->iar_sha,
sdl->sdl_alen = iar->iar_arp.ar_hln);
if (rt->rt_expire)
rt->rt_expire = time.tv_sec + ieee1394arpt_keep;
rt->rt_flags &= ~RTF_REJECT;
la->la_asked = 0;
s = splnet();
mold = la->la_hold;
la->la_hold = 0;
splx(s);
if (mold) {
arpstat.as_dfrsent++;
(*ifp->if_output)(ifp, mold, rt_key(rt), rt);
}
}
reply:
if (op != ARPOP_REQUEST) {
if (op == ARPOP_REPLY)
arpstat.as_rcvreply++;
out:
m_freem(m);
return;
}
arpstat.as_rcvrequest++;
if (in_hosteq(itaddr, myaddr)) {
/* I am the target */
memcpy(&iar->iar_sha, LLADDR(ifp->if_sadl), ifp->if_addrlen);
} else {
la = ieee1394arplookup(&itaddr, 0, SIN_PROXY);
if (la == 0)
goto out;
rt = la->la_rt;
sdl = SDL(rt->rt_gateway);
memcpy(&iar->iar_sha, LLADDR(sdl), ifp->if_addrlen);
}
memcpy(&iar->iar_tip, &iar->iar_sip, sizeof(struct in_addr));
memcpy(&iar->iar_sip, &itaddr, sizeof(struct in_addr));
iar->iar_arp.ar_op = htons(ARPOP_REPLY);
iar->iar_arp.ar_pro = htons(ETHERTYPE_IP); /* let's be sure! */
iar->iar_arp.ar_hrd = htons(ARPHRD_IEEE1394);
m->m_flags |= M_BCAST; /* reply by broadcast */
m->m_len = sizeof(*iar);
m->m_pkthdr.len = m->m_len;
sa.sa_family = AF_ARP;
sa.sa_len = 2;
arpstat.as_sndtotal++;
arpstat.as_sndreply++;
(*ifp->if_output)(ifp, m, &sa, (struct rtentry *)0);
return;
}
/*
* Lookup or enter a new address in ieee1394arptab.
*/
static struct llinfo_arp *
ieee1394arplookup(struct in_addr *addr, int create, int proxy)
{
struct rtentry *rt;
static struct sockaddr_inarp sin;
const char *why = 0;
sin.sin_len = sizeof(sin);
sin.sin_family = AF_INET;
sin.sin_addr = *addr;
sin.sin_other = proxy ? SIN_PROXY : 0;
rt = rtalloc1(sintosa(&sin), create);
if (rt == 0)
return (0);
rt->rt_refcnt--;
if (rt->rt_flags & RTF_GATEWAY)
why = "host is not on local network";
else if ((rt->rt_flags & RTF_LLINFO) == 0) {
arpstat.as_allocfail++;
why = "could not allocate llinfo";
} else if (rt->rt_gateway->sa_family != AF_LINK)
why = "gateway route is not ours";
else
return ((struct llinfo_arp *)rt->rt_llinfo);
if (create)
log(LOG_DEBUG, "ieee1394arplookup: unable to enter address"
" for %s (%s)\n",
in_fmtaddr(*addr), why);
return (0);
}
void
ieee1394arp_ifinit(struct ifnet *ifp, struct ifaddr *ifa)
{
struct in_addr *ip;
/*
* Warn the user if another station has this IP address,
* but only if the interface IP address is not zero.
*/
ip = &IA_SIN(ifa)->sin_addr;
if (!in_nullhost(*ip))
ieee1394arprequest(ifp, ip, ip);
ifa->ifa_rtrequest = ieee1394arp_rtrequest;
ifa->ifa_flags |= RTF_CLONING;
}