freebsd-dev/sys/netatalk/aarp.c
Robert Watson a7320549ac Introduce experimental support for MAC in the AppleTalk/EtherTalk stack.
Label link layer mbufs as they are created for transmission, check
mbufs before delivering them to sockets, label mbufs as they are created
from sockets, and preserve mbuf labels if mbufs are copied.

Obtained from:	TrustedBSD Project
Sponsored by:	DARPA, NAI Labs
2002-08-15 18:58:44 +00:00

627 lines
16 KiB
C

/*
* Copyright (c) 1990,1991 Regents of The University of Michigan.
* All Rights Reserved.
*
* $FreeBSD$
*/
#include "opt_atalk.h"
#include "opt_mac.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mac.h>
#include <sys/mbuf.h>
#include <sys/kernel.h>
#include <sys/socket.h>
#include <sys/syslog.h>
#include <net/if.h>
#include <netinet/in.h>
#undef s_net
#include <netinet/if_ether.h>
#include <netatalk/at.h>
#include <netatalk/at_var.h>
#include <netatalk/aarp.h>
#include <netatalk/phase2.h>
#include <netatalk/at_extern.h>
static void aarptfree( struct aarptab *aat);
static void at_aarpinput( struct arpcom *ac, struct mbuf *m);
#define AARPTAB_BSIZ 9
#define AARPTAB_NB 19
#define AARPTAB_SIZE (AARPTAB_BSIZ * AARPTAB_NB)
static struct aarptab aarptab[AARPTAB_SIZE];
#define AARPTAB_HASH(a) \
((((a).s_net << 8 ) + (a).s_node ) % AARPTAB_NB )
#define AARPTAB_LOOK(aat,addr) { \
int n; \
aat = &aarptab[ AARPTAB_HASH(addr) * AARPTAB_BSIZ ]; \
for ( n = 0; n < AARPTAB_BSIZ; n++, aat++ ) \
if ( aat->aat_ataddr.s_net == (addr).s_net && \
aat->aat_ataddr.s_node == (addr).s_node ) \
break; \
if ( n >= AARPTAB_BSIZ ) \
aat = 0; \
}
#define AARPT_AGE (60 * 1)
#define AARPT_KILLC 20
#define AARPT_KILLI 3
# if !defined( __FreeBSD__ )
extern u_char etherbroadcastaddr[6];
# endif /* __FreeBSD__ */
static u_char atmulticastaddr[ 6 ] = {
0x09, 0x00, 0x07, 0xff, 0xff, 0xff,
};
u_char at_org_code[ 3 ] = {
0x08, 0x00, 0x07,
};
u_char aarp_org_code[ 3 ] = {
0x00, 0x00, 0x00,
};
static struct callout_handle aarptimer_ch =
CALLOUT_HANDLE_INITIALIZER(&aarptimer_ch);
static void
aarptimer(void *ignored)
{
struct aarptab *aat;
int i, s;
aarptimer_ch = timeout( aarptimer, (caddr_t)0, AARPT_AGE * hz );
aat = aarptab;
for ( i = 0; i < AARPTAB_SIZE; i++, aat++ ) {
if ( aat->aat_flags == 0 || ( aat->aat_flags & ATF_PERM ))
continue;
if ( ++aat->aat_timer < (( aat->aat_flags & ATF_COM ) ?
AARPT_KILLC : AARPT_KILLI ))
continue;
s = splimp();
aarptfree( aat );
splx( s );
}
}
/*
* search through the network addresses to find one that includes
* the given network.. remember to take netranges into
* consideration.
*/
struct at_ifaddr *
at_ifawithnet(struct sockaddr_at *sat )
{
struct at_ifaddr *aa;
struct sockaddr_at *sat2;
for ( aa = at_ifaddr; aa; aa = aa->aa_next ) {
sat2 = &(aa->aa_addr);
if ( sat2->sat_addr.s_net == sat->sat_addr.s_net ) {
break;
}
if( (aa->aa_flags & AFA_PHASE2 )
&& (ntohs(aa->aa_firstnet) <= ntohs(sat->sat_addr.s_net))
&& (ntohs(aa->aa_lastnet) >= ntohs(sat->sat_addr.s_net))) {
break;
}
}
return( aa );
}
static void
aarpwhohas( struct arpcom *ac, struct sockaddr_at *sat )
{
struct mbuf *m;
struct ether_header *eh;
struct ether_aarp *ea;
struct at_ifaddr *aa;
struct llc *llc;
struct sockaddr sa;
if (( m = m_gethdr( M_DONTWAIT, MT_DATA )) == NULL ) {
return;
}
#ifdef MAC
mac_create_mbuf_linklayer(&ac->ac_if, m);
#endif
m->m_len = sizeof( *ea );
m->m_pkthdr.len = sizeof( *ea );
MH_ALIGN( m, sizeof( *ea ));
ea = mtod( m, struct ether_aarp *);
bzero((caddr_t)ea, sizeof( *ea ));
ea->aarp_hrd = htons( AARPHRD_ETHER );
ea->aarp_pro = htons( ETHERTYPE_AT );
ea->aarp_hln = sizeof( ea->aarp_sha );
ea->aarp_pln = sizeof( ea->aarp_spu );
ea->aarp_op = htons( AARPOP_REQUEST );
bcopy((caddr_t)ac->ac_enaddr, (caddr_t)ea->aarp_sha,
sizeof( ea->aarp_sha ));
/*
* We need to check whether the output ethernet type should
* be phase 1 or 2. We have the interface that we'll be sending
* the aarp out. We need to find an AppleTalk network on that
* interface with the same address as we're looking for. If the
* net is phase 2, generate an 802.2 and SNAP header.
*/
if ((aa = at_ifawithnet( sat )) == NULL) {
m_freem( m );
return;
}
eh = (struct ether_header *)sa.sa_data;
if ( aa->aa_flags & AFA_PHASE2 ) {
bcopy((caddr_t)atmulticastaddr, (caddr_t)eh->ether_dhost,
sizeof( eh->ether_dhost ));
eh->ether_type = htons(sizeof(struct llc) + sizeof(struct ether_aarp));
M_PREPEND( m, sizeof( struct llc ), M_TRYWAIT );
llc = mtod( m, struct llc *);
llc->llc_dsap = llc->llc_ssap = LLC_SNAP_LSAP;
llc->llc_control = LLC_UI;
bcopy( aarp_org_code, llc->llc_org_code, sizeof( aarp_org_code ));
llc->llc_ether_type = htons( ETHERTYPE_AARP );
bcopy( &AA_SAT( aa )->sat_addr.s_net, ea->aarp_spnet,
sizeof( ea->aarp_spnet ));
bcopy( &sat->sat_addr.s_net, ea->aarp_tpnet,
sizeof( ea->aarp_tpnet ));
ea->aarp_spnode = AA_SAT( aa )->sat_addr.s_node;
ea->aarp_tpnode = sat->sat_addr.s_node;
} else {
bcopy((caddr_t)etherbroadcastaddr, (caddr_t)eh->ether_dhost,
sizeof( eh->ether_dhost ));
eh->ether_type = htons( ETHERTYPE_AARP );
ea->aarp_spa = AA_SAT( aa )->sat_addr.s_node;
ea->aarp_tpa = sat->sat_addr.s_node;
}
#ifdef NETATALKDEBUG
printf("aarp: sending request for %u.%u\n",
ntohs(AA_SAT( aa )->sat_addr.s_net),
AA_SAT( aa )->sat_addr.s_node);
#endif /* NETATALKDEBUG */
sa.sa_len = sizeof( struct sockaddr );
sa.sa_family = AF_UNSPEC;
(*ac->ac_if.if_output)(&ac->ac_if,
m, &sa, NULL); /* XXX NULL should be routing information */
}
int
aarpresolve( ac, m, destsat, desten )
struct arpcom *ac;
struct mbuf *m;
struct sockaddr_at *destsat;
u_char *desten;
{
struct at_ifaddr *aa;
struct aarptab *aat;
int s;
if ( at_broadcast( destsat )) {
m->m_flags |= M_BCAST;
if ((aa = at_ifawithnet( destsat )) == NULL) {
m_freem( m );
return( 0 );
}
if ( aa->aa_flags & AFA_PHASE2 ) {
bcopy( (caddr_t)atmulticastaddr, (caddr_t)desten,
sizeof( atmulticastaddr ));
} else {
bcopy( (caddr_t)etherbroadcastaddr, (caddr_t)desten,
sizeof( etherbroadcastaddr ));
}
return( 1 );
}
s = splimp();
AARPTAB_LOOK( aat, destsat->sat_addr );
if ( aat == 0 ) { /* No entry */
aat = aarptnew( &destsat->sat_addr );
if ( aat == 0 ) {
panic( "aarpresolve: no free entry" );
}
aat->aat_hold = m;
aarpwhohas( ac, destsat );
splx( s );
return( 0 );
}
/* found an entry */
aat->aat_timer = 0;
if ( aat->aat_flags & ATF_COM ) { /* entry is COMplete */
bcopy( (caddr_t)aat->aat_enaddr, (caddr_t)desten,
sizeof( aat->aat_enaddr ));
splx( s );
return( 1 );
}
/* entry has not completed */
if ( aat->aat_hold ) {
m_freem( aat->aat_hold );
}
aat->aat_hold = m;
aarpwhohas( ac, destsat );
splx( s );
return( 0 );
}
void
aarpinput( ac, m )
struct arpcom *ac;
struct mbuf *m;
{
struct arphdr *ar;
if ( ac->ac_if.if_flags & IFF_NOARP )
goto out;
if ( m->m_len < sizeof( struct arphdr )) {
goto out;
}
ar = mtod( m, struct arphdr *);
if ( ntohs( ar->ar_hrd ) != AARPHRD_ETHER ) {
goto out;
}
if ( m->m_len < sizeof( struct arphdr ) + 2 * ar->ar_hln +
2 * ar->ar_pln ) {
goto out;
}
switch( ntohs( ar->ar_pro )) {
case ETHERTYPE_AT :
at_aarpinput( ac, m );
return;
default:
break;
}
out:
m_freem( m );
}
static void
at_aarpinput( struct arpcom *ac, struct mbuf *m)
{
struct ether_aarp *ea;
struct at_ifaddr *aa;
struct aarptab *aat;
struct ether_header *eh;
struct llc *llc;
struct sockaddr_at sat;
struct sockaddr sa;
struct at_addr spa, tpa, ma;
int op;
u_short net;
ea = mtod( m, struct ether_aarp *);
/* Check to see if from my hardware address */
if ( !bcmp(( caddr_t )ea->aarp_sha, ( caddr_t )ac->ac_enaddr,
sizeof( ac->ac_enaddr ))) {
m_freem( m );
return;
}
op = ntohs( ea->aarp_op );
bcopy( ea->aarp_tpnet, &net, sizeof( net ));
if ( net != 0 ) { /* should be ATADDR_ANYNET? */
sat.sat_len = sizeof(struct sockaddr_at);
sat.sat_family = AF_APPLETALK;
sat.sat_addr.s_net = net;
if ((aa = at_ifawithnet( &sat )) == NULL) {
m_freem( m );
return;
}
bcopy( ea->aarp_spnet, &spa.s_net, sizeof( spa.s_net ));
bcopy( ea->aarp_tpnet, &tpa.s_net, sizeof( tpa.s_net ));
} else {
/*
* Since we don't know the net, we just look for the first
* phase 1 address on the interface.
*/
for (aa = (struct at_ifaddr *)TAILQ_FIRST(&ac->ac_if.if_addrhead); aa;
aa = (struct at_ifaddr *)aa->aa_ifa.ifa_link.tqe_next) {
if ( AA_SAT( aa )->sat_family == AF_APPLETALK &&
( aa->aa_flags & AFA_PHASE2 ) == 0 ) {
break;
}
}
if ( aa == NULL ) {
m_freem( m );
return;
}
tpa.s_net = spa.s_net = AA_SAT( aa )->sat_addr.s_net;
}
spa.s_node = ea->aarp_spnode;
tpa.s_node = ea->aarp_tpnode;
ma.s_net = AA_SAT( aa )->sat_addr.s_net;
ma.s_node = AA_SAT( aa )->sat_addr.s_node;
/*
* This looks like it's from us.
*/
if ( spa.s_net == ma.s_net && spa.s_node == ma.s_node ) {
if ( aa->aa_flags & AFA_PROBING ) {
/*
* We're probing, someone either responded to our probe, or
* probed for the same address we'd like to use. Change the
* address we're probing for.
*/
untimeout( aarpprobe, ac, aa->aa_ch );
wakeup( aa );
m_freem( m );
return;
} else if ( op != AARPOP_PROBE ) {
/*
* This is not a probe, and we're not probing. This means
* that someone's saying they have the same source address
* as the one we're using. Get upset...
*/
log( LOG_ERR,
"aarp: duplicate AT address!! %x:%x:%x:%x:%x:%x\n",
ea->aarp_sha[ 0 ], ea->aarp_sha[ 1 ], ea->aarp_sha[ 2 ],
ea->aarp_sha[ 3 ], ea->aarp_sha[ 4 ], ea->aarp_sha[ 5 ]);
m_freem( m );
return;
}
}
AARPTAB_LOOK( aat, spa );
if ( aat ) {
if ( op == AARPOP_PROBE ) {
/*
* Someone's probing for spa, dealocate the one we've got,
* so that if the prober keeps the address, we'll be able
* to arp for him.
*/
aarptfree( aat );
m_freem( m );
return;
}
bcopy(( caddr_t )ea->aarp_sha, ( caddr_t )aat->aat_enaddr,
sizeof( ea->aarp_sha ));
aat->aat_flags |= ATF_COM;
if ( aat->aat_hold ) {
struct mbuf *mhold = aat->aat_hold;
aat->aat_hold = NULL;
sat.sat_len = sizeof(struct sockaddr_at);
sat.sat_family = AF_APPLETALK;
sat.sat_addr = spa;
(*ac->ac_if.if_output)( &ac->ac_if, mhold,
(struct sockaddr *)&sat, NULL); /* XXX */
}
} else if ((tpa.s_net == ma.s_net)
&& (tpa.s_node == ma.s_node)
&& (op != AARPOP_PROBE)
&& ((aat = aarptnew( &spa )) != NULL)) {
bcopy(( caddr_t )ea->aarp_sha, ( caddr_t )aat->aat_enaddr,
sizeof( ea->aarp_sha ));
aat->aat_flags |= ATF_COM;
}
/*
* Don't respond to responses, and never respond if we're
* still probing.
*/
if ( tpa.s_net != ma.s_net || tpa.s_node != ma.s_node ||
op == AARPOP_RESPONSE || ( aa->aa_flags & AFA_PROBING )) {
m_freem( m );
return;
}
bcopy(( caddr_t )ea->aarp_sha, ( caddr_t )ea->aarp_tha,
sizeof( ea->aarp_sha ));
bcopy(( caddr_t )ac->ac_enaddr, ( caddr_t )ea->aarp_sha,
sizeof( ea->aarp_sha ));
/* XXX */
eh = (struct ether_header *)sa.sa_data;
bcopy(( caddr_t )ea->aarp_tha, ( caddr_t )eh->ether_dhost,
sizeof( eh->ether_dhost ));
if ( aa->aa_flags & AFA_PHASE2 ) {
eh->ether_type = htons( sizeof( struct llc ) +
sizeof( struct ether_aarp ));
M_PREPEND( m, sizeof( struct llc ), M_DONTWAIT );
if ( m == NULL ) {
return;
}
llc = mtod( m, struct llc *);
llc->llc_dsap = llc->llc_ssap = LLC_SNAP_LSAP;
llc->llc_control = LLC_UI;
bcopy( aarp_org_code, llc->llc_org_code, sizeof( aarp_org_code ));
llc->llc_ether_type = htons( ETHERTYPE_AARP );
bcopy( ea->aarp_spnet, ea->aarp_tpnet, sizeof( ea->aarp_tpnet ));
bcopy( &ma.s_net, ea->aarp_spnet, sizeof( ea->aarp_spnet ));
} else {
eh->ether_type = htons( ETHERTYPE_AARP );
}
ea->aarp_tpnode = ea->aarp_spnode;
ea->aarp_spnode = ma.s_node;
ea->aarp_op = htons( AARPOP_RESPONSE );
sa.sa_len = sizeof( struct sockaddr );
sa.sa_family = AF_UNSPEC;
(*ac->ac_if.if_output)( &ac->ac_if, m, &sa, NULL); /* XXX */
return;
}
static void
aarptfree( struct aarptab *aat)
{
if ( aat->aat_hold )
m_freem( aat->aat_hold );
aat->aat_hold = NULL;
aat->aat_timer = aat->aat_flags = 0;
aat->aat_ataddr.s_net = 0;
aat->aat_ataddr.s_node = 0;
}
struct aarptab *
aarptnew( addr )
struct at_addr *addr;
{
int n;
int oldest = -1;
struct aarptab *aat, *aato = NULL;
static int first = 1;
if ( first ) {
first = 0;
aarptimer_ch = timeout( aarptimer, (caddr_t)0, hz );
}
aat = &aarptab[ AARPTAB_HASH( *addr ) * AARPTAB_BSIZ ];
for ( n = 0; n < AARPTAB_BSIZ; n++, aat++ ) {
if ( aat->aat_flags == 0 )
goto out;
if ( aat->aat_flags & ATF_PERM )
continue;
if ((int) aat->aat_timer > oldest ) {
oldest = aat->aat_timer;
aato = aat;
}
}
if ( aato == NULL )
return( NULL );
aat = aato;
aarptfree( aat );
out:
aat->aat_ataddr = *addr;
aat->aat_flags = ATF_INUSE;
return( aat );
}
void
aarpprobe( void *arg )
{
struct arpcom *ac = arg;
struct mbuf *m;
struct ether_header *eh;
struct ether_aarp *ea;
struct at_ifaddr *aa;
struct llc *llc;
struct sockaddr sa;
/*
* We need to check whether the output ethernet type should
* be phase 1 or 2. We have the interface that we'll be sending
* the aarp out. We need to find an AppleTalk network on that
* interface with the same address as we're looking for. If the
* net is phase 2, generate an 802.2 and SNAP header.
*/
for (aa = (struct at_ifaddr *)TAILQ_FIRST(&ac->ac_if.if_addrhead); aa;
aa = (struct at_ifaddr *)aa->aa_ifa.ifa_link.tqe_next) {
if ( AA_SAT( aa )->sat_family == AF_APPLETALK &&
( aa->aa_flags & AFA_PROBING )) {
break;
}
}
if ( aa == NULL ) { /* serious error XXX */
printf( "aarpprobe why did this happen?!\n" );
return;
}
if ( aa->aa_probcnt <= 0 ) {
aa->aa_flags &= ~AFA_PROBING;
wakeup( aa );
return;
} else {
aa->aa_ch = timeout( aarpprobe, (caddr_t)ac, hz / 5 );
}
if (( m = m_gethdr( M_DONTWAIT, MT_DATA )) == NULL ) {
return;
}
#ifdef MAC
mac_create_mbuf_linklayer(&ac->ac_if, m);
#endif
m->m_len = sizeof( *ea );
m->m_pkthdr.len = sizeof( *ea );
MH_ALIGN( m, sizeof( *ea ));
ea = mtod( m, struct ether_aarp *);
bzero((caddr_t)ea, sizeof( *ea ));
ea->aarp_hrd = htons( AARPHRD_ETHER );
ea->aarp_pro = htons( ETHERTYPE_AT );
ea->aarp_hln = sizeof( ea->aarp_sha );
ea->aarp_pln = sizeof( ea->aarp_spu );
ea->aarp_op = htons( AARPOP_PROBE );
bcopy((caddr_t)ac->ac_enaddr, (caddr_t)ea->aarp_sha,
sizeof( ea->aarp_sha ));
eh = (struct ether_header *)sa.sa_data;
if ( aa->aa_flags & AFA_PHASE2 ) {
bcopy((caddr_t)atmulticastaddr, (caddr_t)eh->ether_dhost,
sizeof( eh->ether_dhost ));
eh->ether_type = htons( sizeof( struct llc ) +
sizeof( struct ether_aarp ));
M_PREPEND( m, sizeof( struct llc ), M_TRYWAIT );
llc = mtod( m, struct llc *);
llc->llc_dsap = llc->llc_ssap = LLC_SNAP_LSAP;
llc->llc_control = LLC_UI;
bcopy( aarp_org_code, llc->llc_org_code, sizeof( aarp_org_code ));
llc->llc_ether_type = htons( ETHERTYPE_AARP );
bcopy( &AA_SAT( aa )->sat_addr.s_net, ea->aarp_spnet,
sizeof( ea->aarp_spnet ));
bcopy( &AA_SAT( aa )->sat_addr.s_net, ea->aarp_tpnet,
sizeof( ea->aarp_tpnet ));
ea->aarp_spnode = ea->aarp_tpnode = AA_SAT( aa )->sat_addr.s_node;
} else {
bcopy((caddr_t)etherbroadcastaddr, (caddr_t)eh->ether_dhost,
sizeof( eh->ether_dhost ));
eh->ether_type = htons( ETHERTYPE_AARP );
ea->aarp_spa = ea->aarp_tpa = AA_SAT( aa )->sat_addr.s_node;
}
#ifdef NETATALKDEBUG
printf("aarp: sending probe for %u.%u\n",
ntohs(AA_SAT( aa )->sat_addr.s_net),
AA_SAT( aa )->sat_addr.s_node);
#endif /* NETATALKDEBUG */
sa.sa_len = sizeof( struct sockaddr );
sa.sa_family = AF_UNSPEC;
(*ac->ac_if.if_output)(&ac->ac_if, m, &sa, NULL); /* XXX */
aa->aa_probcnt--;
}
void
aarp_clean(void)
{
struct aarptab *aat;
int i;
untimeout( aarptimer, 0, aarptimer_ch );
for ( i = 0, aat = aarptab; i < AARPTAB_SIZE; i++, aat++ ) {
if ( aat->aat_hold ) {
m_freem( aat->aat_hold );
aat->aat_hold = NULL;
}
}
}