1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
|
/*-
* Copyright (c) 2004-2009 Robert N. M. Watson
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* Copyright (c) 1990, 1994 Regents of The University of Michigan.
*
* 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.
*
* 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
*
* $FreeBSD$
*/
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/mbuf.h>
#include <sys/signalvar.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/sx.h>
#include <sys/systm.h>
#include <net/if.h>
#include <net/route.h>
#include <netatalk/at.h>
#include <netatalk/at_var.h>
#include <netatalk/ddp.h>
#include <netatalk/ddp_var.h>
#include <netatalk/ddp_pcb.h>
#include <netatalk/at_extern.h>
#include <security/mac/mac_framework.h>
static volatile int ddp_forward = 1;
static volatile int ddp_firewall = 0;
static struct ddpstat ddpstat;
static struct route forwro;
static void ddp_input(struct mbuf *, struct ifnet *, struct elaphdr *, int);
/*
* Could probably merge these two code segments a little better...
*/
void
at2intr(struct mbuf *m)
{
/*
* Phase 2 packet handling .
*/
ddp_input(m, m->m_pkthdr.rcvif, NULL, 2);
}
void
at1intr(struct mbuf *m)
{
struct elaphdr *elhp, elh;
/*
* Phase 1 packet handling
*/
if (m->m_len < SZ_ELAPHDR && ((m = m_pullup(m, SZ_ELAPHDR)) ==
NULL)) {
ddpstat.ddps_tooshort++;
return;
}
/*
* This seems a little dubious, but I don't know phase 1 so leave it.
*/
elhp = mtod(m, struct elaphdr *);
m_adj(m, SZ_ELAPHDR);
if (elhp->el_type != ELAP_DDPEXTEND) {
bcopy((caddr_t)elhp, (caddr_t)&elh, SZ_ELAPHDR);
ddp_input(m, m->m_pkthdr.rcvif, &elh, 1);
} else
ddp_input(m, m->m_pkthdr.rcvif, NULL, 1);
}
static void
ddp_input(struct mbuf *m, struct ifnet *ifp, struct elaphdr *elh, int phase)
{
struct sockaddr_at from, to;
struct ddpshdr *dsh, ddps;
struct at_ifaddr *aa;
struct ddpehdr *deh = NULL, ddpe;
struct ddpcb *ddp;
int dlen, mlen;
u_short cksum = 0;
bzero((caddr_t)&from, sizeof(struct sockaddr_at));
bzero((caddr_t)&to, sizeof(struct sockaddr_at));
if (elh != NULL) {
/*
* Extract the information in the short header. Network
* information is defaulted to ATADDR_ANYNET and node
* information comes from the elh info. We must be phase 1.
*/
ddpstat.ddps_short++;
if (m->m_len < sizeof(struct ddpshdr) &&
((m = m_pullup(m, sizeof(struct ddpshdr))) == NULL)) {
ddpstat.ddps_tooshort++;
return;
}
dsh = mtod(m, struct ddpshdr *);
bcopy((caddr_t)dsh, (caddr_t)&ddps, sizeof(struct ddpshdr));
ddps.dsh_bytes = ntohl(ddps.dsh_bytes);
dlen = ddps.dsh_len;
to.sat_addr.s_net = ATADDR_ANYNET;
to.sat_addr.s_node = elh->el_dnode;
to.sat_port = ddps.dsh_dport;
from.sat_addr.s_net = ATADDR_ANYNET;
from.sat_addr.s_node = elh->el_snode;
from.sat_port = ddps.dsh_sport;
/*
* Make sure that we point to the phase1 ifaddr info and that
* it's valid for this packet.
*/
AT_IFADDR_RLOCK();
for (aa = at_ifaddr_list; aa != NULL; aa = aa->aa_next) {
if ((aa->aa_ifp == ifp)
&& ((aa->aa_flags & AFA_PHASE2) == 0)
&& ((to.sat_addr.s_node ==
AA_SAT(aa)->sat_addr.s_node) ||
(to.sat_addr.s_node == ATADDR_BCAST)))
break;
}
/*
* maybe we got a broadcast not meant for us.. ditch it.
*/
if (aa == NULL) {
AT_IFADDR_RUNLOCK();
m_freem(m);
return;
}
} else {
/*
* There was no 'elh' passed on. This could still be either
* phase1 or phase2. We have a long header, but we may be
* running on a phase 1 net. Extract out all the info
* regarding this packet's src & dst.
*/
ddpstat.ddps_long++;
if (m->m_len < sizeof(struct ddpehdr) &&
((m = m_pullup(m, sizeof(struct ddpehdr))) == NULL)) {
AT_IFADDR_RUNLOCK();
ddpstat.ddps_tooshort++;
return;
}
deh = mtod(m, struct ddpehdr *);
bcopy((caddr_t)deh, (caddr_t)&ddpe, sizeof(struct ddpehdr));
ddpe.deh_bytes = ntohl(ddpe.deh_bytes);
dlen = ddpe.deh_len;
if ((cksum = ddpe.deh_sum) == 0)
ddpstat.ddps_nosum++;
from.sat_addr.s_net = ddpe.deh_snet;
from.sat_addr.s_node = ddpe.deh_snode;
from.sat_port = ddpe.deh_sport;
to.sat_addr.s_net = ddpe.deh_dnet;
to.sat_addr.s_node = ddpe.deh_dnode;
to.sat_port = ddpe.deh_dport;
AT_IFADDR_RLOCK();
if (to.sat_addr.s_net == ATADDR_ANYNET) {
/*
* The TO address doesn't specify a net, so by
* definition it's for this net. Try find ifaddr
* info with the right phase, the right interface,
* and either to our node, a broadcast, or looped
* back (though that SHOULD be covered in the other
* cases).
*
* XXX If we have multiple interfaces, then the first
* with this node number will match (which may NOT be
* what we want, but it's probably safe in 99.999% of
* cases.
*/
for (aa = at_ifaddr_list; aa != NULL;
aa = aa->aa_next) {
if (phase == 1 && (aa->aa_flags &
AFA_PHASE2))
continue;
if (phase == 2 && (aa->aa_flags &
AFA_PHASE2) == 0)
continue;
if ((aa->aa_ifp == ifp) &&
((to.sat_addr.s_node ==
AA_SAT(aa)->sat_addr.s_node) ||
(to.sat_addr.s_node == ATADDR_BCAST) ||
(ifp->if_flags & IFF_LOOPBACK)))
break;
}
} else {
/*
* A destination network was given. We just try to
* find which ifaddr info matches it.
*/
for (aa = at_ifaddr_list; aa != NULL;
aa = aa->aa_next) {
/*
* This is a kludge. Accept packets that are
* for any router on a local netrange.
*/
if (to.sat_addr.s_net == aa->aa_firstnet &&
to.sat_addr.s_node == 0)
break;
/*
* Don't use ifaddr info for which we are
* totally outside the netrange, and it's not
* a startup packet. Startup packets are
* always implicitly allowed on to the next
* test.
*/
if (((ntohs(to.sat_addr.s_net) <
ntohs(aa->aa_firstnet)) ||
(ntohs(to.sat_addr.s_net) >
ntohs(aa->aa_lastnet))) &&
((ntohs(to.sat_addr.s_net) < 0xff00) ||
(ntohs(to.sat_addr.s_net) > 0xfffe)))
continue;
/*
* Don't record a match either if we just
* don't have a match in the node address.
* This can have if the interface is in
* promiscuous mode for example.
*/
if ((to.sat_addr.s_node !=
AA_SAT(aa)->sat_addr.s_node) &&
(to.sat_addr.s_node != ATADDR_BCAST))
continue;
break;
}
}
}
if (aa != NULL)
ifa_ref(&aa->aa_ifa);
AT_IFADDR_RUNLOCK();
/*
* Adjust the length, removing any padding that may have been added
* at a link layer. We do this before we attempt to forward a
* packet, possibly on a different media.
*/
mlen = m->m_pkthdr.len;
if (mlen < dlen) {
ddpstat.ddps_toosmall++;
goto out;
}
if (mlen > dlen)
m_adj(m, dlen - mlen);
/*
* If it isn't for a net on any of our interfaces, or it IS for a net
* on a different interface than it came in on, (and it is not looped
* back) then consider if we should forward it. As we are not really
* a router this is a bit cheeky, but it may be useful some day.
*/
if ((aa == NULL) || ((to.sat_addr.s_node == ATADDR_BCAST) &&
(aa->aa_ifp != ifp) && ((ifp->if_flags & IFF_LOOPBACK) == 0))) {
/*
* If we've explicitly disabled it, don't route anything.
*/
if (ddp_forward == 0)
goto out;
/*
* If the cached forwarding route is still valid, use it.
*
* XXXRW: Access to the cached route may not be properly
* synchronized for parallel input handling.
*/
if (forwro.ro_rt &&
(satosat(&forwro.ro_dst)->sat_addr.s_net !=
to.sat_addr.s_net ||
satosat(&forwro.ro_dst)->sat_addr.s_node !=
to.sat_addr.s_node)) {
RTFREE(forwro.ro_rt);
forwro.ro_rt = NULL;
}
/*
* If we don't have a cached one (any more) or it's useless,
* then get a new route.
*
* XXX this could cause a 'route leak'. Check this!
*/
if (forwro.ro_rt == NULL || forwro.ro_rt->rt_ifp == NULL) {
forwro.ro_dst.sa_len = sizeof(struct sockaddr_at);
forwro.ro_dst.sa_family = AF_APPLETALK;
satosat(&forwro.ro_dst)->sat_addr.s_net =
to.sat_addr.s_net;
satosat(&forwro.ro_dst)->sat_addr.s_node =
to.sat_addr.s_node;
rtalloc(&forwro);
}
/*
* If it's not going to get there on this hop, and it's
* already done too many hops, then throw it away.
*/
if ((to.sat_addr.s_net !=
satosat(&forwro.ro_dst)->sat_addr.s_net) &&
(ddpe.deh_hops == DDP_MAXHOPS))
goto out;
/*
* A ddp router might use the same interface to forward the
* packet, which this would not effect. Don't allow packets
* to cross from one interface to another however.
*/
if (ddp_firewall && ((forwro.ro_rt == NULL) ||
(forwro.ro_rt->rt_ifp != ifp)))
goto out;
/*
* Adjust the header. If it was a short header then it would
* have not gotten here, so we can assume there is room to
* drop the header in.
*
* XXX what about promiscuous mode, etc...
*/
ddpe.deh_hops++;
ddpe.deh_bytes = htonl(ddpe.deh_bytes);
/* XXX deh? */
bcopy((caddr_t)&ddpe, (caddr_t)deh, sizeof(u_short));
if (ddp_route(m, &forwro))
ddpstat.ddps_cantforward++;
else
ddpstat.ddps_forward++;
if (aa != NULL)
ifa_free(&aa->aa_ifa);
return;
}
/*
* It was for us, and we have an ifaddr to use with it.
*/
from.sat_len = sizeof(struct sockaddr_at);
from.sat_family = AF_APPLETALK;
/*
* We are no longer interested in the link layer so cut it off.
*/
if (elh == NULL) {
if (ddp_cksum && cksum && cksum !=
at_cksum(m, sizeof(int))) {
ddpstat.ddps_badsum++;
goto out;
}
m_adj(m, sizeof(struct ddpehdr));
} else
m_adj(m, sizeof(struct ddpshdr));
/*
* Search for ddp protocol control blocks that match these addresses.
*/
DDP_LIST_SLOCK();
if ((ddp = ddp_search(&from, &to, aa)) == NULL)
goto out_unlock;
#ifdef MAC
if (mac_socket_check_deliver(ddp->ddp_socket, m) != 0)
goto out_unlock;
#endif
/*
* If we found one, deliver the packet to the socket
*/
SOCKBUF_LOCK(&ddp->ddp_socket->so_rcv);
if (sbappendaddr_locked(&ddp->ddp_socket->so_rcv,
(struct sockaddr *)&from, m, NULL) == 0) {
SOCKBUF_UNLOCK(&ddp->ddp_socket->so_rcv);
/*
* If the socket is full (or similar error) dump the packet.
*/
ddpstat.ddps_nosockspace++;
goto out_unlock;
}
/*
* And wake up whatever might be waiting for it
*/
sorwakeup_locked(ddp->ddp_socket);
m = NULL;
out_unlock:
DDP_LIST_SUNLOCK();
out:
if (aa != NULL)
ifa_free(&aa->aa_ifa);
if (m != NULL)
m_freem(m);
}
|