FreeBSD-5.3/sys/netatalk/ddp_input.c
/*
* Copyright (c) 2004 Robert N. M. Watson
* 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.
*/
/*
* Copyright (c) 1990,1994 Regents of The University of Michigan.
*
* Permission to use, copy, modify, and distribute this software and
* its documentation for any purpose and without fee is hereby granted,
* provided that the above copyright notice appears in all copies and
* that both that copyright notice and this permission notice appear
* in supporting documentation, and that the name of The University
* of Michigan not be used in advertising or publicity pertaining to
* distribution of the software without specific, written prior
* permission. This software is supplied as is without expressed or
* implied warranties of any kind.
*
* This product includes software developed by the University of
* California, Berkeley and its contributors.
*
* Research Systems Unix Group
* The University of Michigan
* c/o Wesley Craig
* 535 W. William Street
* Ann Arbor, Michigan
* +1-313-764-2278
* netatalk@umich.edu
*
* $FreeBSD: src/sys/netatalk/ddp_input.c,v 1.26 2004/08/10 03:23:05 rwatson Exp $
*/
#include "opt_mac.h"
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/mac.h>
#include <sys/mbuf.h>
#include <sys/signalvar.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sx.h>
#include <sys/systm.h>
#include <net/if.h>
#include <net/route.h>
#include <netatalk/at.h>
#include <netatalk/at_var.h>
#include <netatalk/ddp.h>
#include <netatalk/ddp_var.h>
#include <netatalk/ddp_pcb.h>
#include <netatalk/at_extern.h>
static volatile int ddp_forward = 1;
static volatile int ddp_firewall = 0;
static struct ddpstat ddpstat;
static struct route forwro;
static void ddp_input(struct mbuf *, struct ifnet *, struct elaphdr *, int);
/*
* Could probably merge these two code segments a little better...
*/
void
at2intr(struct mbuf *m)
{
/*
* Phase 2 packet handling
*/
ddp_input(m, m->m_pkthdr.rcvif, NULL, 2);
return;
}
void
at1intr(struct mbuf *m)
{
struct elaphdr *elhp, elh;
/*
* Phase 1 packet handling
*/
if (m->m_len < SZ_ELAPHDR && ((m = m_pullup(m, SZ_ELAPHDR)) == NULL)) {
ddpstat.ddps_tooshort++;
return;
}
/*
* This seems a little dubious, but I don't know phase 1 so leave it.
*/
elhp = mtod(m, struct elaphdr *);
m_adj(m, SZ_ELAPHDR);
if (elhp->el_type == ELAP_DDPEXTEND) {
ddp_input(m, m->m_pkthdr.rcvif, NULL, 1);
} else {
bcopy((caddr_t)elhp, (caddr_t)&elh, SZ_ELAPHDR);
ddp_input(m, m->m_pkthdr.rcvif, &elh, 1);
}
return;
}
static void
ddp_input(m, ifp, elh, phase)
struct mbuf *m;
struct ifnet *ifp;
struct elaphdr *elh;
int phase;
{
struct sockaddr_at from, to;
struct ddpshdr *dsh, ddps;
struct at_ifaddr *aa;
struct ddpehdr *deh = NULL, ddpe;
struct ddpcb *ddp;
int dlen, mlen;
u_short cksum = 0;
bzero((caddr_t)&from, sizeof(struct sockaddr_at));
bzero((caddr_t)&to, sizeof(struct sockaddr_at));
if (elh != NULL) {
/*
* Extract the information in the short header.
* netowrk information is defaulted to ATADDR_ANYNET
* and node information comes from the elh info.
* We must be phase 1.
*/
ddpstat.ddps_short++;
if (m->m_len < sizeof(struct ddpshdr) &&
((m = m_pullup(m, sizeof(struct ddpshdr))) == NULL)) {
ddpstat.ddps_tooshort++;
return;
}
dsh = mtod(m, struct ddpshdr *);
bcopy((caddr_t)dsh, (caddr_t)&ddps, sizeof(struct ddpshdr));
ddps.dsh_bytes = ntohl(ddps.dsh_bytes);
dlen = ddps.dsh_len;
to.sat_addr.s_net = ATADDR_ANYNET;
to.sat_addr.s_node = elh->el_dnode;
to.sat_port = ddps.dsh_dport;
from.sat_addr.s_net = ATADDR_ANYNET;
from.sat_addr.s_node = elh->el_snode;
from.sat_port = ddps.dsh_sport;
/*
* Make sure that we point to the phase1 ifaddr info
* and that it's valid for this packet.
*/
for (aa = at_ifaddr_list; aa != NULL; aa = aa->aa_next) {
if ((aa->aa_ifp == ifp)
&& ((aa->aa_flags & AFA_PHASE2) == 0)
&& ((to.sat_addr.s_node == AA_SAT(aa)->sat_addr.s_node)
|| (to.sat_addr.s_node == ATADDR_BCAST))) {
break;
}
}
/*
* maybe we got a broadcast not meant for us.. ditch it.
*/
if (aa == NULL) {
m_freem(m);
return;
}
} else {
/*
* There was no 'elh' passed on. This could still be
* either phase1 or phase2.
* We have a long header, but we may be running on a phase 1 net.
* Extract out all the info regarding this packet's src & dst.
*/
ddpstat.ddps_long++;
if (m->m_len < sizeof(struct ddpehdr) &&
((m = m_pullup(m, sizeof(struct ddpehdr))) == NULL)) {
ddpstat.ddps_tooshort++;
return;
}
deh = mtod(m, struct ddpehdr *);
bcopy((caddr_t)deh, (caddr_t)&ddpe, sizeof(struct ddpehdr));
ddpe.deh_bytes = ntohl(ddpe.deh_bytes);
dlen = ddpe.deh_len;
if ((cksum = ddpe.deh_sum) == 0) {
ddpstat.ddps_nosum++;
}
from.sat_addr.s_net = ddpe.deh_snet;
from.sat_addr.s_node = ddpe.deh_snode;
from.sat_port = ddpe.deh_sport;
to.sat_addr.s_net = ddpe.deh_dnet;
to.sat_addr.s_node = ddpe.deh_dnode;
to.sat_port = ddpe.deh_dport;
if (to.sat_addr.s_net == ATADDR_ANYNET) {
/*
* The TO address doesn't specify a net,
* So by definition it's for this net.
* Try find ifaddr info with the right phase,
* the right interface, and either to our node, a broadcast,
* or looped back (though that SHOULD be covered in the other
* cases).
*
* XXX If we have multiple interfaces, then the first with
* this node number will match (which may NOT be what we want,
* but it's probably safe in 99.999% of cases.
*/
for (aa = at_ifaddr_list; aa != NULL; aa = aa->aa_next) {
if (phase == 1 && (aa->aa_flags & AFA_PHASE2)) {
continue;
}
if (phase == 2 && (aa->aa_flags & AFA_PHASE2) == 0) {
continue;
}
if ((aa->aa_ifp == ifp)
&& ((to.sat_addr.s_node == AA_SAT(aa)->sat_addr.s_node)
|| (to.sat_addr.s_node == ATADDR_BCAST)
|| (ifp->if_flags & IFF_LOOPBACK))) {
break;
}
}
} else {
/*
* A destination network was given. We just try to find
* which ifaddr info matches it.
*/
for (aa = at_ifaddr_list; aa != NULL; aa = aa->aa_next) {
/*
* This is a kludge. Accept packets that are
* for any router on a local netrange.
*/
if (to.sat_addr.s_net == aa->aa_firstnet &&
to.sat_addr.s_node == 0) {
break;
}
/*
* Don't use ifaddr info for which we are totally outside the
* netrange, and it's not a startup packet.
* Startup packets are always implicitly allowed on to
* the next test.
*/
if (((ntohs(to.sat_addr.s_net) < ntohs(aa->aa_firstnet))
|| (ntohs(to.sat_addr.s_net) > ntohs(aa->aa_lastnet)))
&& ((ntohs(to.sat_addr.s_net) < 0xff00)
|| (ntohs(to.sat_addr.s_net) > 0xfffe))) {
continue;
}
/*
* Don't record a match either if we just don't have a match
* in the node address. This can have if the interface
* is in promiscuous mode for example.
*/
if ((to.sat_addr.s_node != AA_SAT(aa)->sat_addr.s_node)
&& (to.sat_addr.s_node != ATADDR_BCAST)) {
continue;
}
break;
}
}
}
/*
* Adjust the length, removing any padding that may have been added
* at a link layer. We do this before we attempt to forward a packet,
* possibly on a different media.
*/
mlen = m->m_pkthdr.len;
if (mlen < dlen) {
ddpstat.ddps_toosmall++;
m_freem(m);
return;
}
if (mlen > dlen) {
m_adj(m, dlen - mlen);
}
/*
* If it aint for a net on any of our interfaces,
* or it IS for a net on a different interface than it came in on,
* (and it is not looped back) then consider if we should forward it.
* As we are not really a router this is a bit cheeky, but it may be
* useful some day.
*/
if ((aa == NULL)
|| ((to.sat_addr.s_node == ATADDR_BCAST)
&& (aa->aa_ifp != ifp)
&& ((ifp->if_flags & IFF_LOOPBACK) == 0))) {
/*
* If we've explicitly disabled it, don't route anything
*/
if (ddp_forward == 0) {
m_freem(m);
return;
}
/*
* If the cached forwarding route is still valid, use it.
*/
if (forwro.ro_rt
&& (satosat(&forwro.ro_dst)->sat_addr.s_net != to.sat_addr.s_net
|| satosat(&forwro.ro_dst)->sat_addr.s_node != to.sat_addr.s_node)) {
RTFREE(forwro.ro_rt);
forwro.ro_rt = NULL;
}
/*
* If we don't have a cached one (any more) or it's useless,
* Then get a new route.
* XXX this could cause a 'route leak'. check this!
*/
if (forwro.ro_rt == NULL || forwro.ro_rt->rt_ifp == NULL) {
forwro.ro_dst.sa_len = sizeof(struct sockaddr_at);
forwro.ro_dst.sa_family = AF_APPLETALK;
satosat(&forwro.ro_dst)->sat_addr.s_net = to.sat_addr.s_net;
satosat(&forwro.ro_dst)->sat_addr.s_node = to.sat_addr.s_node;
rtalloc(&forwro);
}
/*
* If it's not going to get there on this hop, and it's
* already done too many hops, then throw it away.
*/
if ((to.sat_addr.s_net != satosat(&forwro.ro_dst)->sat_addr.s_net)
&& (ddpe.deh_hops == DDP_MAXHOPS)) {
m_freem(m);
return;
}
/*
* A ddp router might use the same interface
* to forward the packet, which this would not effect.
* Don't allow packets to cross from one interface to another however.
*/
if (ddp_firewall
&& ((forwro.ro_rt == NULL)
|| (forwro.ro_rt->rt_ifp != ifp))) {
m_freem(m);
return;
}
/*
* Adjust the header.
* If it was a short header then it would have not gotten here,
* so we can assume there is room to drop the header in.
* XXX what about promiscuous mode, etc...
*/
ddpe.deh_hops++;
ddpe.deh_bytes = htonl(ddpe.deh_bytes);
bcopy((caddr_t)&ddpe, (caddr_t)deh, sizeof(u_short)); /* XXX deh? */
if (ddp_route(m, &forwro)) {
ddpstat.ddps_cantforward++;
} else {
ddpstat.ddps_forward++;
}
return;
}
/*
* It was for us, and we have an ifaddr to use with it.
*/
from.sat_len = sizeof(struct sockaddr_at);
from.sat_family = AF_APPLETALK;
/*
* We are no longer interested in the link layer.
* so cut it off.
*/
if (elh != NULL) {
m_adj(m, sizeof(struct ddpshdr));
} else {
if (ddp_cksum && cksum && cksum != at_cksum(m, sizeof(int))) {
ddpstat.ddps_badsum++;
m_freem(m);
return;
}
m_adj(m, sizeof(struct ddpehdr));
}
/*
* Search for ddp protocol control blocks that match these
* addresses.
*/
DDP_LIST_SLOCK();
if ((ddp = ddp_search(&from, &to, aa)) == NULL) {
goto out;
}
#ifdef MAC
SOCK_LOCK(ddp->ddp_socket);
if (mac_check_socket_deliver(ddp->ddp_socket, m) != 0) {
SOCK_UNLOCK(ddp->ddp_socket);
goto out;
}
SOCK_UNLOCK(ddp->ddp_socket);
#endif
/*
* If we found one, deliver th epacket to the socket
*/
if (sbappendaddr(&ddp->ddp_socket->so_rcv, (struct sockaddr *)&from,
m, NULL) == 0) {
/*
* If the socket is full (or similar error) dump the packet.
*/
ddpstat.ddps_nosockspace++;
goto out;
}
/*
* And wake up whatever might be waiting for it
*/
sorwakeup(ddp->ddp_socket);
m = NULL;
out:
DDP_LIST_SUNLOCK();
if (m != NULL)
m_freem(m);
}
#if 0
/* As if we haven't got enough of this sort of think floating
around the kernel :) */
#define BPXLEN 48
#define BPALEN 16
#include <ctype.h>
char hexdig[] = "0123456789ABCDEF";
static void
bprint(char *data, int len)
{
char xout[ BPXLEN ], aout[ BPALEN ];
int i = 0;
bzero(xout, BPXLEN);
bzero(aout, BPALEN);
for (;;) {
if (len < 1) {
if (i != 0) {
printf("%s\t%s\n", xout, aout);
}
printf("%s\n", "(end)");
break;
}
xout[ (i*3) ] = hexdig[ (*data & 0xf0) >> 4 ];
xout[ (i*3) + 1 ] = hexdig[ *data & 0x0f ];
if ((u_char)*data < 0x7f && (u_char)*data > 0x20) {
aout[ i ] = *data;
} else {
aout[ i ] = '.';
}
xout[ (i*3) + 2 ] = ' ';
i++;
len--;
data++;
if (i > BPALEN - 2) {
printf("%s\t%s\n", xout, aout);
bzero(xout, BPXLEN);
bzero(aout, BPALEN);
i = 0;
continue;
}
}
}
static void
m_printm(struct mbuf *m)
{
for (; m; m = m->m_next) {
bprint(mtod(m, char *), m->m_len);
}
}
#endif