1 /* $NetBSD: ddp_output.c,v 1.15 2011/07/17 20:54:53 joerg 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 1.15 2011/07/17 20:54:53 joerg 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 int ddp_cksum = 1; 53 54 int 55 ddp_output(struct mbuf *m,...) 56 { 57 struct ddpcb *ddp; 58 struct ddpehdr *deh; 59 va_list ap; 60 61 va_start(ap, m); 62 ddp = va_arg(ap, struct ddpcb *); 63 va_end(ap); 64 65 M_PREPEND(m, sizeof(struct ddpehdr), M_DONTWAIT); 66 if (!m) 67 return (ENOBUFS); 68 69 deh = mtod(m, struct ddpehdr *); 70 deh->deh_pad = 0; 71 deh->deh_hops = 0; 72 73 deh->deh_len = m->m_pkthdr.len; 74 75 deh->deh_dnet = ddp->ddp_fsat.sat_addr.s_net; 76 deh->deh_dnode = ddp->ddp_fsat.sat_addr.s_node; 77 deh->deh_dport = ddp->ddp_fsat.sat_port; 78 deh->deh_snet = ddp->ddp_lsat.sat_addr.s_net; 79 deh->deh_snode = ddp->ddp_lsat.sat_addr.s_node; 80 deh->deh_sport = ddp->ddp_lsat.sat_port; 81 82 /* 83 * The checksum calculation is done after all of the other bytes have 84 * been filled in. 85 */ 86 if (ddp_cksum) 87 deh->deh_sum = at_cksum(m, sizeof(int)); 88 else 89 deh->deh_sum = 0; 90 deh->deh_bytes = htonl(deh->deh_bytes); 91 92 return ddp_route(m, &ddp->ddp_route); 93 } 94 95 u_short 96 at_cksum(struct mbuf *m, int skip) 97 { 98 u_char *data, *end; 99 u_long cksum = 0; 100 101 for (; m; m = m->m_next) { 102 for (data = mtod(m, u_char *), end = data + m->m_len; 103 data < end; data++) { 104 if (skip) { 105 skip--; 106 continue; 107 } 108 cksum = (cksum + *data) << 1; 109 if (cksum & 0x00010000) 110 cksum++; 111 cksum &= 0x0000ffff; 112 } 113 } 114 115 if (cksum == 0) { 116 cksum = 0x0000ffff; 117 } 118 return (u_short)cksum; 119 } 120 121 int 122 ddp_route(struct mbuf *m, struct route *ro) 123 { 124 struct rtentry *rt; 125 struct sockaddr_at gate; 126 struct elaphdr *elh; 127 struct at_ifaddr *aa = NULL; 128 struct ifnet *ifp = NULL; 129 u_short net; 130 131 if ((rt = rtcache_validate(ro)) != NULL && (ifp = rt->rt_ifp) != NULL) { 132 net = satosat(rt->rt_gateway)->sat_addr.s_net; 133 TAILQ_FOREACH(aa, &at_ifaddr, aa_list) { 134 if (aa->aa_ifp == ifp && 135 ntohs(net) >= ntohs(aa->aa_firstnet) && 136 ntohs(net) <= ntohs(aa->aa_lastnet)) { 137 break; 138 } 139 } 140 } 141 if (aa == NULL) { 142 printf("%s: no address found\n", __func__); 143 m_freem(m); 144 return EINVAL; 145 } 146 /* 147 * There are several places in the kernel where data is added to 148 * an mbuf without ensuring that the mbuf pointer is aligned. 149 * This is bad for transition routing, since phase 1 and phase 2 150 * packets end up poorly aligned due to the three byte elap header. 151 */ 152 if (!(aa->aa_flags & AFA_PHASE2)) { 153 M_PREPEND(m, SZ_ELAPHDR, M_DONTWAIT); 154 if (m == NULL) 155 return ENOBUFS; 156 157 elh = mtod(m, struct elaphdr *); 158 elh->el_snode = satosat(&aa->aa_addr)->sat_addr.s_node; 159 elh->el_type = ELAP_DDPEXTEND; 160 if (ntohs(satocsat(rtcache_getdst(ro))->sat_addr.s_net) >= 161 ntohs(aa->aa_firstnet) && 162 ntohs(satocsat(rtcache_getdst(ro))->sat_addr.s_net) <= 163 ntohs(aa->aa_lastnet)) { 164 elh->el_dnode = satocsat(rtcache_getdst(ro))->sat_addr.s_node; 165 } else { 166 elh->el_dnode = 167 satosat(rt->rt_gateway)->sat_addr.s_node; 168 } 169 } 170 if (ntohs(satocsat(rtcache_getdst(ro))->sat_addr.s_net) >= 171 ntohs(aa->aa_firstnet) && 172 ntohs(satocsat(rtcache_getdst(ro))->sat_addr.s_net) <= 173 ntohs(aa->aa_lastnet)) { 174 gate = *satocsat(rtcache_getdst(ro)); 175 } else { 176 gate = *satosat(rt->rt_gateway); 177 } 178 rt->rt_use++; 179 180 #if IFA_STATS 181 aa->aa_ifa.ifa_data.ifad_outbytes += m->m_pkthdr.len; 182 #endif 183 184 /* XXX */ 185 return (*ifp->if_output)(ifp, m, (struct sockaddr *)&gate, NULL); 186 } 187