/* $OpenBSD: aarp.c,v 1.6 2006/03/04 22:40:16 brad Exp $ */ /* * Copyright (c) 1990,1991 Regents of The University of Michigan. * All Rights Reserved. */ /* * The following is the contents of the COPYRIGHT file from the * netatalk-1.4a2 distribution, from which this file is derived. */ /* * Copyright (c) 1990,1996 Regents of The University of Michigan. * * All Rights Reserved. * * 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. * * Solaris code is encumbered by the following: * * Copyright (C) 1996 by Sun Microsystems Computer Co. * * 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 appear in all * copies and that both that copyright notice and this permission * notice appear in supporting documentation. This software is * provided "as is" without express or implied warranty. * * 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 */ /* * None of the Solaris code mentioned is included in OpenBSD. * This code also relies heavily on previous effort in FreeBSD and NetBSD. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #undef s_net #include #include #include #include #include #include #include #include #include static void aarptimer(void *); struct ifaddr *at_ifawithnet(struct sockaddr_at *, struct ifaddr *); static void aarpwhohas(struct arpcom *, struct sockaddr_at *); int aarpresolve(struct arpcom *, struct mbuf *, struct sockaddr_at *, u_int8_t *); void aarpinput(struct arpcom *, struct mbuf *); static void at_aarpinput(struct arpcom *, struct mbuf *); static void aarptfree(struct aarptab *); struct aarptab *aarptnew(struct at_addr *); void aarpprobe(void *); void aarp_clean(void); #ifdef GATEWAY #define AARPTAB_BSIZ 16 #define AARPTAB_NB 37 #else #define AARPTAB_BSIZ 9 #define AARPTAB_NB 19 #endif /* GATEWAY */ #define AARPTAB_SIZE (AARPTAB_BSIZ * AARPTAB_NB) struct aarptab aarptab[AARPTAB_SIZE]; int aarptab_size = AARPTAB_SIZE; struct timeout aarpprobe_timeout; struct timeout aarptimer_timeout; #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 u_int8_t atmulticastaddr[ 6 ] = { 0x09, 0x00, 0x07, 0xff, 0xff, 0xff, }; u_int8_t at_org_code[ 3 ] = { 0x08, 0x00, 0x07, }; u_int8_t aarp_org_code[ 3 ] = { 0x00, 0x00, 0x00, }; /*ARGSUSED*/ static void aarptimer(v) void *v; { struct aarptab *aat; int i, s; timeout_add(&aarptimer_timeout, 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 = splnet(); aarptfree( aat ); splx( s ); } } struct ifaddr * at_ifawithnet( sat, ifa ) struct sockaddr_at *sat; struct ifaddr *ifa; { struct sockaddr_at *sat2; struct netrange *nr; for (; ifa; ifa = ifa->ifa_list.tqe_next ) { if ( ifa->ifa_addr->sa_family != AF_APPLETALK ) { continue; } sat2 = satosat( ifa->ifa_addr ); if ( sat2->sat_addr.s_net == sat->sat_addr.s_net ) { break; } nr = (struct netrange *)(sat2->sat_zero); if( (nr->nr_phase == 2 ) && (nr->nr_firstnet <= sat->sat_addr.s_net) && (nr->nr_lastnet >= sat->sat_addr.s_net)) { break; } } return( ifa ); } static void aarpwhohas( ac, sat ) 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 = (struct at_ifaddr *) at_ifawithnet( sat, ac->ac_if.if_addrlist.tqh_first )) == 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(AT_LLC_SIZE + sizeof(struct ether_aarp)); M_PREPEND( m, AT_LLC_SIZE, M_DONTWAIT ); if (!m) 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( &AA_SAT( aa )->sat_addr.s_net, ea->aarp_spnet, sizeof( ea->aarp_spnet )); ea->aarp_spnode = AA_SAT( aa )->sat_addr.s_node; bcopy( &sat->sat_addr.s_net, ea->aarp_tpnet, sizeof( ea->aarp_tpnet )); 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; } sa.sa_len = sizeof( struct sockaddr ); sa.sa_family = AF_UNSPEC; /* XXX The NULL should be a struct rtentry. TBD */ (*ac->ac_if.if_output)(&ac->ac_if, m, &sa , NULL); } int aarpresolve( ac, m, destsat, desten ) struct arpcom *ac; struct mbuf *m; struct sockaddr_at *destsat; u_int8_t *desten; { struct at_ifaddr *aa; struct aarptab *aat; int s; if ( at_broadcast( destsat )) { if (( aa = (struct at_ifaddr *)at_ifawithnet( destsat, ((struct ifnet *)ac)->if_addrlist.tqh_first )) == 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 = splnet(); AARPTAB_LOOK( aat, destsat->sat_addr ); if ( aat == 0 ) { /* No entry */ aat = aarptnew( &destsat->sat_addr ); if ( aat == 0 ) { /* XXX allocate more */ 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( ac, m ) 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_int16_t 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; } /* * Check if from broadcast address. This could be a more robust * check, since we could look for multicasts. XXX */ if ( !bcmp(( caddr_t )ea->aarp_sha, ( caddr_t )etherbroadcastaddr, sizeof( etherbroadcastaddr ))) { log( LOG_ERR, "aarp: source is broadcast!\n" ); m_freem( m ); return; } op = ntohs( ea->aarp_op ); bcopy( ea->aarp_tpnet, &net, sizeof( net )); if ( net != 0 ) { sat.sat_len = sizeof(struct sockaddr_at); sat.sat_family = AF_APPLETALK; sat.sat_addr.s_net = net; if (( aa = (struct at_ifaddr *)at_ifawithnet( &sat, ac->ac_if.if_addrlist.tqh_first )) == 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_addrlist.tqh_first; aa; aa = (struct at_ifaddr *)aa->aa_ifa.ifa_list.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. */ timeout_del(&aarpprobe_timeout); 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... */ /* XXX use ether_ntoa */ 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 ) { sat.sat_len = sizeof(struct sockaddr_at); sat.sat_family = AF_APPLETALK; sat.sat_addr = spa; /* XXX the NULL should be a struct rtentry */ (*ac->ac_if.if_output)( &ac->ac_if, aat->aat_hold, (struct sockaddr *)&sat, NULL ); aat->aat_hold = 0; } } if ( aat == 0 && tpa.s_net == ma.s_net && tpa.s_node == ma.s_node && op != AARPOP_PROBE ) { if ( (aat = aarptnew( &spa ))) { 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 FreeBSD has an 'XXX' here but no comment as to why. */ 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( AT_LLC_SIZE + sizeof( struct ether_aarp )); M_PREPEND( m, AT_LLC_SIZE, 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; /* XXX the NULL should be a struct rtentry */ (*ac->ac_if.if_output)( &ac->ac_if, m, &sa, NULL ); return; } static void aarptfree( aat ) struct aarptab *aat; { if ( aat->aat_hold ) m_freem( aat->aat_hold ); aat->aat_hold = 0; 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; timeout_set(&aarptimer_timeout, aarptimer, NULL); timeout_add(&aarptimer_timeout, 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( arg ) void *arg; { struct arpcom *ac = (struct arpcom *) 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_addrlist.tqh_first; aa; aa = (struct at_ifaddr *)aa->aa_ifa.ifa_list.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 { timeout_set(&aarpprobe_timeout, aarpprobe, ac); timeout_add(&aarpprobe_timeout, 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( AT_LLC_SIZE + sizeof( struct ether_aarp )); M_PREPEND( m, AT_LLC_SIZE, M_DONTWAIT ); if (!m) 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( &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; } sa.sa_len = sizeof( struct sockaddr ); sa.sa_family = AF_UNSPEC; /* XXX the NULL should be a struct rtentry */ (*ac->ac_if.if_output)(&ac->ac_if, m, &sa, NULL ); aa->aa_probcnt--; } void aarp_clean(void) { struct aarptab *aat; int i; timeout_del(&aarptimer_timeout); for ( i = 0, aat = aarptab; i < AARPTAB_SIZE; i++, aat++ ) { if ( aat->aat_hold ) { m_freem( aat->aat_hold ); } } }