1 /* $NetBSD: ddp_output.c,v 1.14 2008/04/06 18:46:56 dyoung Exp $ */ 2 3 /* 4 * Copyright (c) 1990,1991 Regents of The University of Michigan. 5 * All Rights Reserved. 6 * 7 * Permission to use, copy, modify, and distribute this software and 8 * its documentation for any purpose and without fee is hereby granted, 9 * provided that the above copyright notice appears in all copies and 10 * that both that copyright notice and this permission notice appear 11 * in supporting documentation, and that the name of The University 12 * of Michigan not be used in advertising or publicity pertaining to 13 * distribution of the software without specific, written prior 14 * permission. This software is supplied as is without expressed or 15 * implied warranties of any kind. 16 * 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 20 * Research Systems Unix Group 21 * The University of Michigan 22 * c/o Wesley Craig 23 * 535 W. William Street 24 * Ann Arbor, Michigan 25 * +1-313-764-2278 26 * netatalk@umich.edu 27 */ 28 29 #include <sys/cdefs.h> 30 __KERNEL_RCSID(0, "$NetBSD: ddp_output.c,v 1.14 2008/04/06 18:46:56 dyoung Exp $"); 31 32 #include <sys/param.h> 33 #include <sys/systm.h> 34 #include <sys/mbuf.h> 35 #include <sys/socket.h> 36 #include <sys/errno.h> 37 #include <sys/syslog.h> 38 39 #include <net/if.h> 40 #include <net/route.h> 41 #include <net/if_ether.h> 42 43 #include <netinet/in.h> 44 #undef s_net 45 46 #include <netatalk/at.h> 47 #include <netatalk/at_var.h> 48 #include <netatalk/ddp.h> 49 #include <netatalk/ddp_var.h> 50 #include <netatalk/at_extern.h> 51 52 #include <machine/stdarg.h> 53 54 int ddp_cksum = 1; 55 56 int 57 ddp_output(struct mbuf *m,...) 58 { 59 struct ddpcb *ddp; 60 struct ddpehdr *deh; 61 va_list ap; 62 63 va_start(ap, m); 64 ddp = va_arg(ap, struct ddpcb *); 65 va_end(ap); 66 67 M_PREPEND(m, sizeof(struct ddpehdr), M_DONTWAIT); 68 if (!m) 69 return (ENOBUFS); 70 71 deh = mtod(m, struct ddpehdr *); 72 deh->deh_pad = 0; 73 deh->deh_hops = 0; 74 75 deh->deh_len = m->m_pkthdr.len; 76 77 deh->deh_dnet = ddp->ddp_fsat.sat_addr.s_net; 78 deh->deh_dnode = ddp->ddp_fsat.sat_addr.s_node; 79 deh->deh_dport = ddp->ddp_fsat.sat_port; 80 deh->deh_snet = ddp->ddp_lsat.sat_addr.s_net; 81 deh->deh_snode = ddp->ddp_lsat.sat_addr.s_node; 82 deh->deh_sport = ddp->ddp_lsat.sat_port; 83 84 /* 85 * The checksum calculation is done after all of the other bytes have 86 * been filled in. 87 */ 88 if (ddp_cksum) 89 deh->deh_sum = at_cksum(m, sizeof(int)); 90 else 91 deh->deh_sum = 0; 92 deh->deh_bytes = htonl(deh->deh_bytes); 93 94 return ddp_route(m, &ddp->ddp_route); 95 } 96 97 u_short 98 at_cksum(struct mbuf *m, int skip) 99 { 100 u_char *data, *end; 101 u_long cksum = 0; 102 103 for (; m; m = m->m_next) { 104 for (data = mtod(m, u_char *), end = data + m->m_len; 105 data < end; data++) { 106 if (skip) { 107 skip--; 108 continue; 109 } 110 cksum = (cksum + *data) << 1; 111 if (cksum & 0x00010000) 112 cksum++; 113 cksum &= 0x0000ffff; 114 } 115 } 116 117 if (cksum == 0) { 118 cksum = 0x0000ffff; 119 } 120 return (u_short)cksum; 121 } 122 123 int 124 ddp_route(struct mbuf *m, struct route *ro) 125 { 126 struct rtentry *rt; 127 struct sockaddr_at gate; 128 struct elaphdr *elh; 129 struct at_ifaddr *aa = NULL; 130 struct ifnet *ifp = NULL; 131 u_short net; 132 133 if ((rt = rtcache_validate(ro)) != NULL && (ifp = rt->rt_ifp) != NULL) { 134 net = satosat(rt->rt_gateway)->sat_addr.s_net; 135 TAILQ_FOREACH(aa, &at_ifaddr, aa_list) { 136 if (aa->aa_ifp == ifp && 137 ntohs(net) >= ntohs(aa->aa_firstnet) && 138 ntohs(net) <= ntohs(aa->aa_lastnet)) { 139 break; 140 } 141 } 142 } 143 if (aa == NULL) { 144 printf("%s: no address found\n", __func__); 145 m_freem(m); 146 return EINVAL; 147 } 148 /* 149 * There are several places in the kernel where data is added to 150 * an mbuf without ensuring that the mbuf pointer is aligned. 151 * This is bad for transition routing, since phase 1 and phase 2 152 * packets end up poorly aligned due to the three byte elap header. 153 */ 154 if (!(aa->aa_flags & AFA_PHASE2)) { 155 M_PREPEND(m, SZ_ELAPHDR, M_DONTWAIT); 156 if (m == NULL) 157 return ENOBUFS; 158 159 elh = mtod(m, struct elaphdr *); 160 elh->el_snode = satosat(&aa->aa_addr)->sat_addr.s_node; 161 elh->el_type = ELAP_DDPEXTEND; 162 if (ntohs(satocsat(rtcache_getdst(ro))->sat_addr.s_net) >= 163 ntohs(aa->aa_firstnet) && 164 ntohs(satocsat(rtcache_getdst(ro))->sat_addr.s_net) <= 165 ntohs(aa->aa_lastnet)) { 166 elh->el_dnode = satocsat(rtcache_getdst(ro))->sat_addr.s_node; 167 } else { 168 elh->el_dnode = 169 satosat(rt->rt_gateway)->sat_addr.s_node; 170 } 171 } 172 if (ntohs(satocsat(rtcache_getdst(ro))->sat_addr.s_net) >= 173 ntohs(aa->aa_firstnet) && 174 ntohs(satocsat(rtcache_getdst(ro))->sat_addr.s_net) <= 175 ntohs(aa->aa_lastnet)) { 176 gate = *satocsat(rtcache_getdst(ro)); 177 } else { 178 gate = *satosat(rt->rt_gateway); 179 } 180 rt->rt_use++; 181 182 #if IFA_STATS 183 aa->aa_ifa.ifa_data.ifad_outbytes += m->m_pkthdr.len; 184 #endif 185 186 /* XXX */ 187 return (*ifp->if_output)(ifp, m, (struct sockaddr *)&gate, NULL); 188 } 189