/* * Copyright (c) 1990,1991 Regents of The University of Michigan. * All Rights Reserved. * * $FreeBSD: src/sys/netatalk/aarp.c,v 1.12.2.2 2001/06/23 20:43:09 iedowse Exp $ * $DragonFly: src/sys/netproto/atalk/aarp.c,v 1.2 2003/06/17 04:28:48 dillon Exp $ */ #include "opt_atalk.h" #include #include #include #include #include #include #include #include #undef s_net #include #include #include #include #include #include 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; } 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_WAIT ); 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 *)ac->ac_if.if_addrhead.tqh_first; 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 *)ac->ac_if.if_addrhead.tqh_first; 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; } 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_WAIT ); 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; } } }