1 /* $NetBSD: ddp_output.c,v 1.10 2006/10/07 15:49:00 rpaulo 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 1.10 2006/10/07 15:49:00 rpaulo 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 }
93 deh->deh_bytes = htonl(deh->deh_bytes);
94
95 return (ddp_route(m, &ddp->ddp_route));
96 }
97
98 u_short
99 at_cksum(m, skip)
100 struct mbuf *m;
101 int skip;
102 {
103 u_char *data, *end;
104 u_long cksum = 0;
105
106 for (; m; m = m->m_next) {
107 for (data = mtod(m, u_char *), end = data + m->m_len;
108 data < end; data++) {
109 if (skip) {
110 skip--;
111 continue;
112 }
113 cksum = (cksum + *data) << 1;
114 if (cksum & 0x00010000) {
115 cksum++;
116 }
117 cksum &= 0x0000ffff;
118 }
119 }
120
121 if (cksum == 0) {
122 cksum = 0x0000ffff;
123 }
124 return ((u_short) cksum);
125 }
126
127 int
128 ddp_route(m, ro)
129 struct mbuf *m;
130 struct route *ro;
131 {
132 struct sockaddr_at gate;
133 struct elaphdr *elh;
134 struct at_ifaddr *aa = NULL;
135 struct ifnet *ifp = NULL;
136 u_short net;
137
138 if (ro->ro_rt && (ifp = ro->ro_rt->rt_ifp)) {
139 net = satosat(ro->ro_rt->rt_gateway)->sat_addr.s_net;
140 for (aa = at_ifaddr.tqh_first; aa; aa = aa->aa_list.tqe_next) {
141 if (aa->aa_ifp == ifp &&
142 ntohs(net) >= ntohs(aa->aa_firstnet) &&
143 ntohs(net) <= ntohs(aa->aa_lastnet)) {
144 break;
145 }
146 }
147 }
148 if (aa == NULL) {
149 printf("ddp_route: no address found\n");
150 m_freem(m);
151 return (EINVAL);
152 }
153 /*
154 * There are several places in the kernel where data is added to
155 * an mbuf without ensuring that the mbuf pointer is aligned.
156 * This is bad for transition routing, since phase 1 and phase 2
157 * packets end up poorly aligned due to the three byte elap header.
158 */
159 if (!(aa->aa_flags & AFA_PHASE2)) {
160 M_PREPEND(m, SZ_ELAPHDR, M_DONTWAIT);
161 if (!m)
162 return (ENOBUFS);
163
164 elh = mtod(m, struct elaphdr *);
165 elh->el_snode = satosat(&aa->aa_addr)->sat_addr.s_node;
166 elh->el_type = ELAP_DDPEXTEND;
167 if (ntohs(satosat(&ro->ro_dst)->sat_addr.s_net) >=
168 ntohs(aa->aa_firstnet) &&
169 ntohs(satosat(&ro->ro_dst)->sat_addr.s_net) <=
170 ntohs(aa->aa_lastnet)) {
171 elh->el_dnode = satosat(&ro->ro_dst)->sat_addr.s_node;
172 } else {
173 elh->el_dnode =
174 satosat(ro->ro_rt->rt_gateway)->sat_addr.s_node;
175 }
176 }
177 if (ntohs(satosat(&ro->ro_dst)->sat_addr.s_net) >=
178 ntohs(aa->aa_firstnet) &&
179 ntohs(satosat(&ro->ro_dst)->sat_addr.s_net) <=
180 ntohs(aa->aa_lastnet)) {
181 gate = *satosat(&ro->ro_dst);
182 } else {
183 gate = *satosat(ro->ro_rt->rt_gateway);
184 }
185 ro->ro_rt->rt_use++;
186
187 #if IFA_STATS
188 aa->aa_ifa.ifa_data.ifad_outbytes += m->m_pkthdr.len;
189 #endif
190
191 /* XXX */
192 return ((*ifp->if_output) (ifp, m, (struct sockaddr *) &gate, NULL));
193 }
Cache object: 201b7221eb2235b0360a5622489d6b16
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