-
Notifications
You must be signed in to change notification settings - Fork 5
/
af_ipx.c
2124 lines (1808 loc) · 50.6 KB
/
af_ipx.c
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
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/*
* Implements an IPX socket layer.
*
* This code is derived from work by
* Ross Biro : Writing the original IP stack
* Fred Van Kempen : Tidying up the TCP/IP
*
* Many thanks go to Keith Baker, Institute For Industrial Information
* Technology Ltd, Swansea University for allowing me to work on this
* in my own time even though it was in some ways related to commercial
* work I am currently employed to do there.
*
* All the material in this file is subject to the Gnu license version 2.
* Neither Alan Cox nor the Swansea University Computer Society admit
* liability nor provide warranty for any of this software. This material
* is provided as is and at no charge.
*
* Portions Copyright (c) 2000-2003 Conectiva, Inc. <[email protected]>
* Neither Arnaldo Carvalho de Melo nor Conectiva, Inc. admit liability nor
* provide warranty for any of this software. This material is provided
* "AS-IS" and at no charge.
*
* Portions Copyright (c) 1995 Caldera, Inc. <[email protected]>
* Neither Greg Page nor Caldera, Inc. admit liability nor provide
* warranty for any of this software. This material is provided
* "AS-IS" and at no charge.
*
* See net/ipx/ChangeLog.
*/
#include <linux/capability.h>
#include <linux/errno.h>
#include <linux/if_arp.h>
#include <linux/if_ether.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/net.h>
#include <linux/netdevice.h>
#include <linux/uio.h>
#include <linux/slab.h>
#include <linux/skbuff.h>
#include <linux/socket.h>
#include <linux/sockios.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/termios.h>
#include <linux/version.h>
#include <net/p8022.h>
#include <net/psnap.h>
#include <net/sock.h>
#include <net/datalink.h>
#include <net/tcp_states.h>
#include <net/net_namespace.h>
#include <linux/uaccess.h>
#if LINUX_VERSION_CODE < KERNEL_VERSION(5,15,0)
#include <linux/ipx.h>
#else
#include "linux/ipx.h"
#endif
#include "net/ipx.h"
#if LINUX_VERSION_CODE >= KERNEL_VERSION(6,3,0)
#define sk_refcnt_debug_inc(sk) do { } while (0)
#define sk_refcnt_debug_dec(sk) do { } while (0)
#define sk_refcnt_debug_release(sk) do { } while (0)
#endif
/* Configuration Variables */
static unsigned char ipxcfg_max_hops = 16;
static char ipxcfg_auto_select_primary;
static char ipxcfg_auto_create_interfaces;
int sysctl_ipx_pprop_broadcasting = 1;
/* Global Variables */
static struct datalink_proto *p8022_datalink;
static struct datalink_proto *pEII_datalink;
static struct datalink_proto *p8023_datalink;
static struct datalink_proto *pSNAP_datalink;
static const struct proto_ops ipx_dgram_ops;
LIST_HEAD(ipx_interfaces);
DEFINE_SPINLOCK(ipx_interfaces_lock);
struct ipx_interface *ipx_primary_net;
struct ipx_interface *ipx_internal_net;
struct ipx_interface *ipx_interfaces_head(void)
{
struct ipx_interface *rc = NULL;
if (!list_empty(&ipx_interfaces))
rc = list_entry(ipx_interfaces.next,
struct ipx_interface, node);
return rc;
}
static void ipxcfg_set_auto_select(char val)
{
ipxcfg_auto_select_primary = val;
if (val && !ipx_primary_net)
ipx_primary_net = ipx_interfaces_head();
}
static int ipxcfg_get_config_data(struct ipx_config_data __user *arg)
{
struct ipx_config_data vals;
vals.ipxcfg_auto_create_interfaces = ipxcfg_auto_create_interfaces;
vals.ipxcfg_auto_select_primary = ipxcfg_auto_select_primary;
return copy_to_user(arg, &vals, sizeof(vals)) ? -EFAULT : 0;
}
/*
* Note: Sockets may not be removed _during_ an interrupt or inet_bh
* handler using this technique. They can be added although we do not
* use this facility.
*/
static void ipx_remove_socket(struct sock *sk)
{
/* Determine interface with which socket is associated */
struct ipx_interface *intrfc = ipx_sk(sk)->intrfc;
if (!intrfc)
goto out;
ipxitf_hold(intrfc);
spin_lock_bh(&intrfc->if_sklist_lock);
sk_del_node_init(sk);
spin_unlock_bh(&intrfc->if_sklist_lock);
ipxitf_put(intrfc);
out:
return;
}
static void ipx_destroy_socket(struct sock *sk)
{
ipx_remove_socket(sk);
skb_queue_purge(&sk->sk_receive_queue);
sk_refcnt_debug_dec(sk);
}
/*
* The following code is used to support IPX Interfaces (IPXITF). An
* IPX interface is defined by a physical device and a frame type.
*/
/* ipxitf_clear_primary_net has to be called with ipx_interfaces_lock held */
static void ipxitf_clear_primary_net(void)
{
ipx_primary_net = NULL;
if (ipxcfg_auto_select_primary)
ipx_primary_net = ipx_interfaces_head();
}
static struct ipx_interface *__ipxitf_find_using_phys(struct net_device *dev,
__be16 datalink)
{
struct ipx_interface *i;
list_for_each_entry(i, &ipx_interfaces, node)
if (i->if_dev == dev && i->if_dlink_type == datalink)
goto out;
i = NULL;
out:
return i;
}
static struct ipx_interface *ipxitf_find_using_phys(struct net_device *dev,
__be16 datalink)
{
struct ipx_interface *i;
spin_lock_bh(&ipx_interfaces_lock);
i = __ipxitf_find_using_phys(dev, datalink);
if (i)
ipxitf_hold(i);
spin_unlock_bh(&ipx_interfaces_lock);
return i;
}
struct ipx_interface *ipxitf_find_using_net(__be32 net)
{
struct ipx_interface *i;
spin_lock_bh(&ipx_interfaces_lock);
if (net) {
list_for_each_entry(i, &ipx_interfaces, node)
if (i->if_netnum == net)
goto hold;
i = NULL;
goto unlock;
}
i = ipx_primary_net;
if (i)
hold:
ipxitf_hold(i);
unlock:
spin_unlock_bh(&ipx_interfaces_lock);
return i;
}
/* Sockets are bound to a particular IPX interface. */
static void ipxitf_insert_socket(struct ipx_interface *intrfc, struct sock *sk)
{
ipxitf_hold(intrfc);
spin_lock_bh(&intrfc->if_sklist_lock);
ipx_sk(sk)->intrfc = intrfc;
sk_add_node(sk, &intrfc->if_sklist);
spin_unlock_bh(&intrfc->if_sklist_lock);
ipxitf_put(intrfc);
}
/* caller must hold intrfc->if_sklist_lock */
static struct sock *__ipxitf_find_socket(struct ipx_interface *intrfc,
__be16 port)
{
struct sock *s;
sk_for_each(s, &intrfc->if_sklist)
if (ipx_sk(s)->port == port)
goto found;
s = NULL;
found:
return s;
}
/* caller must hold a reference to intrfc */
static struct sock *ipxitf_find_socket(struct ipx_interface *intrfc,
__be16 port)
{
struct sock *s;
spin_lock_bh(&intrfc->if_sklist_lock);
s = __ipxitf_find_socket(intrfc, port);
if (s)
sock_hold(s);
spin_unlock_bh(&intrfc->if_sklist_lock);
return s;
}
#ifdef CONFIG_IPX_INTERN
static struct sock *ipxitf_find_internal_socket(struct ipx_interface *intrfc,
unsigned char *ipx_node,
__be16 port)
{
struct sock *s;
ipxitf_hold(intrfc);
spin_lock_bh(&intrfc->if_sklist_lock);
sk_for_each(s, &intrfc->if_sklist) {
struct ipx_sock *ipxs = ipx_sk(s);
if (ipxs->port == port &&
!memcmp(ipx_node, ipxs->node, IPX_NODE_LEN))
goto found;
}
s = NULL;
found:
spin_unlock_bh(&intrfc->if_sklist_lock);
ipxitf_put(intrfc);
return s;
}
#endif
static void __ipxitf_down(struct ipx_interface *intrfc)
{
struct sock *s;
struct hlist_node *t;
/* Delete all routes associated with this interface */
ipxrtr_del_routes(intrfc);
spin_lock_bh(&intrfc->if_sklist_lock);
/* error sockets */
sk_for_each_safe(s, t, &intrfc->if_sklist) {
struct ipx_sock *ipxs = ipx_sk(s);
s->sk_err = ENOLINK;
s->sk_error_report(s);
ipxs->intrfc = NULL;
ipxs->port = 0;
sock_set_flag(s, SOCK_ZAPPED); /* Indicates it is no longer bound */
sk_del_node_init(s);
}
INIT_HLIST_HEAD(&intrfc->if_sklist);
spin_unlock_bh(&intrfc->if_sklist_lock);
/* remove this interface from list */
list_del(&intrfc->node);
/* remove this interface from *special* networks */
if (intrfc == ipx_primary_net)
ipxitf_clear_primary_net();
if (intrfc == ipx_internal_net)
ipx_internal_net = NULL;
if (intrfc->if_dev)
dev_put(intrfc->if_dev);
kfree(intrfc);
}
void ipxitf_down(struct ipx_interface *intrfc)
{
spin_lock_bh(&ipx_interfaces_lock);
__ipxitf_down(intrfc);
spin_unlock_bh(&ipx_interfaces_lock);
}
static void __ipxitf_put(struct ipx_interface *intrfc)
{
if (refcount_dec_and_test(&intrfc->refcnt))
__ipxitf_down(intrfc);
}
static int ipxitf_device_event(struct notifier_block *notifier,
unsigned long event, void *ptr)
{
struct net_device *dev = netdev_notifier_info_to_dev(ptr);
struct ipx_interface *i, *tmp;
if (!net_eq(dev_net(dev), &init_net))
return NOTIFY_DONE;
if (event != NETDEV_DOWN && event != NETDEV_UP)
goto out;
spin_lock_bh(&ipx_interfaces_lock);
list_for_each_entry_safe(i, tmp, &ipx_interfaces, node)
if (i->if_dev == dev) {
if (event == NETDEV_UP)
ipxitf_hold(i);
else
__ipxitf_put(i);
}
spin_unlock_bh(&ipx_interfaces_lock);
out:
return NOTIFY_DONE;
}
static __exit void ipxitf_cleanup(void)
{
struct ipx_interface *i, *tmp;
spin_lock_bh(&ipx_interfaces_lock);
list_for_each_entry_safe(i, tmp, &ipx_interfaces, node)
__ipxitf_put(i);
spin_unlock_bh(&ipx_interfaces_lock);
}
static void ipxitf_def_skb_handler(struct sock *sock, struct sk_buff *skb)
{
if (sock_queue_rcv_skb(sock, skb) < 0)
kfree_skb(skb);
}
/*
* On input skb->sk is NULL. Nobody is charged for the memory.
*/
/* caller must hold a reference to intrfc */
#ifdef CONFIG_IPX_INTERN
static int ipxitf_demux_socket(struct ipx_interface *intrfc,
struct sk_buff *skb, int copy)
{
struct ipxhdr *ipx = ipx_hdr(skb);
int is_broadcast = !memcmp(ipx->ipx_dest.node, ipx_broadcast_node,
IPX_NODE_LEN);
struct sock *s;
int rc;
spin_lock_bh(&intrfc->if_sklist_lock);
sk_for_each(s, &intrfc->if_sklist) {
struct ipx_sock *ipxs = ipx_sk(s);
if (ipxs->port == ipx->ipx_dest.sock &&
(is_broadcast || !memcmp(ipx->ipx_dest.node,
ipxs->node, IPX_NODE_LEN))) {
/* We found a socket to which to send */
struct sk_buff *skb1;
if (copy) {
skb1 = skb_clone(skb, GFP_ATOMIC);
rc = -ENOMEM;
if (!skb1)
goto out;
} else {
skb1 = skb;
copy = 1; /* skb may only be used once */
}
ipxitf_def_skb_handler(s, skb1);
/* On an external interface, one socket can listen */
if (intrfc != ipx_internal_net)
break;
}
}
/* skb was solely for us, and we did not make a copy, so free it. */
if (!copy)
kfree_skb(skb);
rc = 0;
out:
spin_unlock_bh(&intrfc->if_sklist_lock);
return rc;
}
#else
static struct sock *ncp_connection_hack(struct ipx_interface *intrfc,
struct ipxhdr *ipx)
{
/* The packet's target is a NCP connection handler. We want to hand it
* to the correct socket directly within the kernel, so that the
* mars_nwe packet distribution process does not have to do it. Here we
* only care about NCP and BURST packets.
*
* You might call this a hack, but believe me, you do not want a
* complete NCP layer in the kernel, and this is VERY fast as well. */
struct sock *sk = NULL;
int connection = 0;
u8 *ncphdr = (u8 *)(ipx + 1);
if (*ncphdr == 0x22 && *(ncphdr + 1) == 0x22) /* NCP request */
connection = (((int) *(ncphdr + 5)) << 8) | (int) *(ncphdr + 3);
else if (*ncphdr == 0x77 && *(ncphdr + 1) == 0x77) /* BURST packet */
connection = (((int) *(ncphdr + 9)) << 8) | (int) *(ncphdr + 8);
if (connection) {
/* Now we have to look for a special NCP connection handling
* socket. Only these sockets have ipx_ncp_conn != 0, set by
* SIOCIPXNCPCONN. */
spin_lock_bh(&intrfc->if_sklist_lock);
sk_for_each(sk, &intrfc->if_sklist)
if (ipx_sk(sk)->ipx_ncp_conn == connection) {
sock_hold(sk);
goto found;
}
sk = NULL;
found:
spin_unlock_bh(&intrfc->if_sklist_lock);
}
return sk;
}
static int ipxitf_demux_socket(struct ipx_interface *intrfc,
struct sk_buff *skb, int copy)
{
struct ipxhdr *ipx = ipx_hdr(skb);
struct sock *sock1 = NULL, *sock2 = NULL;
struct sk_buff *skb1 = NULL, *skb2 = NULL;
int rc;
if (intrfc == ipx_primary_net && ntohs(ipx->ipx_dest.sock) == 0x451)
sock1 = ncp_connection_hack(intrfc, ipx);
if (!sock1)
/* No special socket found, forward the packet the normal way */
sock1 = ipxitf_find_socket(intrfc, ipx->ipx_dest.sock);
/*
* We need to check if there is a primary net and if
* this is addressed to one of the *SPECIAL* sockets because
* these need to be propagated to the primary net.
* The *SPECIAL* socket list contains: 0x452(SAP), 0x453(RIP) and
* 0x456(Diagnostic).
*/
if (ipx_primary_net && intrfc != ipx_primary_net) {
const int dsock = ntohs(ipx->ipx_dest.sock);
if (dsock == 0x452 || dsock == 0x453 || dsock == 0x456)
/* The appropriate thing to do here is to dup the
* packet and route to the primary net interface via
* ipxitf_send; however, we'll cheat and just demux it
* here. */
sock2 = ipxitf_find_socket(ipx_primary_net,
ipx->ipx_dest.sock);
}
/*
* If there is nothing to do return. The kfree will cancel any charging.
*/
rc = 0;
if (!sock1 && !sock2) {
if (!copy)
kfree_skb(skb);
goto out;
}
/*
* This next segment of code is a little awkward, but it sets it up
* so that the appropriate number of copies of the SKB are made and
* that skb1 and skb2 point to it (them) so that it (they) can be
* demuxed to sock1 and/or sock2. If we are unable to make enough
* copies, we do as much as is possible.
*/
if (copy)
skb1 = skb_clone(skb, GFP_ATOMIC);
else
skb1 = skb;
rc = -ENOMEM;
if (!skb1)
goto out_put;
/* Do we need 2 SKBs? */
if (sock1 && sock2)
skb2 = skb_clone(skb1, GFP_ATOMIC);
else
skb2 = skb1;
if (sock1)
ipxitf_def_skb_handler(sock1, skb1);
if (!skb2)
goto out_put;
if (sock2)
ipxitf_def_skb_handler(sock2, skb2);
rc = 0;
out_put:
if (sock1)
sock_put(sock1);
if (sock2)
sock_put(sock2);
out:
return rc;
}
#endif /* CONFIG_IPX_INTERN */
static struct sk_buff *ipxitf_adjust_skbuff(struct ipx_interface *intrfc,
struct sk_buff *skb)
{
struct sk_buff *skb2;
int in_offset = (unsigned char *)ipx_hdr(skb) - skb->head;
int out_offset = intrfc->if_ipx_offset;
int len;
/* Hopefully, most cases */
if (in_offset >= out_offset)
return skb;
/* Need new SKB */
len = skb->len + out_offset;
skb2 = alloc_skb(len, GFP_ATOMIC);
if (skb2) {
skb_reserve(skb2, out_offset);
skb_reset_network_header(skb2);
skb_reset_transport_header(skb2);
skb_put(skb2, skb->len);
memcpy(ipx_hdr(skb2), ipx_hdr(skb), skb->len);
memcpy(skb2->cb, skb->cb, sizeof(skb->cb));
}
kfree_skb(skb);
return skb2;
}
/* caller must hold a reference to intrfc and the skb has to be unshared */
int ipxitf_send(struct ipx_interface *intrfc, struct sk_buff *skb, char *node)
{
struct ipxhdr *ipx = ipx_hdr(skb);
struct net_device *dev = intrfc->if_dev;
struct datalink_proto *dl = intrfc->if_dlink;
char dest_node[IPX_NODE_LEN];
int send_to_wire = 1;
int addr_len;
ipx->ipx_tctrl = IPX_SKB_CB(skb)->ipx_tctrl;
ipx->ipx_dest.net = IPX_SKB_CB(skb)->ipx_dest_net;
ipx->ipx_source.net = IPX_SKB_CB(skb)->ipx_source_net;
/* see if we need to include the netnum in the route list */
if (IPX_SKB_CB(skb)->last_hop.index >= 0) {
__be32 *last_hop = (__be32 *)(((u8 *) skb->data) +
sizeof(struct ipxhdr) +
IPX_SKB_CB(skb)->last_hop.index *
sizeof(__be32));
*last_hop = IPX_SKB_CB(skb)->last_hop.netnum;
IPX_SKB_CB(skb)->last_hop.index = -1;
}
/*
* We need to know how many skbuffs it will take to send out this
* packet to avoid unnecessary copies.
*/
if (!dl || !dev || dev->flags & IFF_LOOPBACK)
send_to_wire = 0; /* No non looped */
/*
* See if this should be demuxed to sockets on this interface
*
* We want to ensure the original was eaten or that we only use
* up clones.
*/
if (ipx->ipx_dest.net == intrfc->if_netnum) {
/*
* To our own node, loop and free the original.
* The internal net will receive on all node address.
*/
if (intrfc == ipx_internal_net ||
!memcmp(intrfc->if_node, node, IPX_NODE_LEN)) {
/* Don't charge sender */
skb_orphan(skb);
/* Will charge receiver */
return ipxitf_demux_socket(intrfc, skb, 0);
}
/* Broadcast, loop and possibly keep to send on. */
if (!memcmp(ipx_broadcast_node, node, IPX_NODE_LEN)) {
if (!send_to_wire)
skb_orphan(skb);
ipxitf_demux_socket(intrfc, skb, send_to_wire);
if (!send_to_wire)
goto out;
}
}
/*
* If the originating net is not equal to our net; this is routed
* We are still charging the sender. Which is right - the driver
* free will handle this fairly.
*/
if (ipx->ipx_source.net != intrfc->if_netnum) {
/*
* Unshare the buffer before modifying the count in
* case it's a flood or tcpdump
*/
skb = skb_unshare(skb, GFP_ATOMIC);
if (!skb)
goto out;
if (++ipx->ipx_tctrl > ipxcfg_max_hops)
send_to_wire = 0;
}
if (!send_to_wire) {
kfree_skb(skb);
goto out;
}
/* Determine the appropriate hardware address */
addr_len = dev->addr_len;
if (!memcmp(ipx_broadcast_node, node, IPX_NODE_LEN))
memcpy(dest_node, dev->broadcast, addr_len);
else
memcpy(dest_node, &(node[IPX_NODE_LEN-addr_len]), addr_len);
/* Make any compensation for differing physical/data link size */
skb = ipxitf_adjust_skbuff(intrfc, skb);
if (!skb)
goto out;
/* set up data link and physical headers */
skb->dev = dev;
skb->protocol = htons(ETH_P_IPX);
/* Send it out */
dl->request(dl, skb, dest_node);
out:
return 0;
}
static int ipxitf_add_local_route(struct ipx_interface *intrfc)
{
return ipxrtr_add_route(intrfc->if_netnum, intrfc, NULL);
}
static void ipxitf_discover_netnum(struct ipx_interface *intrfc,
struct sk_buff *skb);
static int ipxitf_pprop(struct ipx_interface *intrfc, struct sk_buff *skb);
static int ipxitf_rcv(struct ipx_interface *intrfc, struct sk_buff *skb)
{
struct ipxhdr *ipx = ipx_hdr(skb);
int rc = 0;
ipxitf_hold(intrfc);
/* See if we should update our network number */
if (!intrfc->if_netnum) /* net number of intrfc not known yet */
ipxitf_discover_netnum(intrfc, skb);
IPX_SKB_CB(skb)->last_hop.index = -1;
if (ipx->ipx_type == IPX_TYPE_PPROP) {
rc = ipxitf_pprop(intrfc, skb);
if (rc)
goto out_free_skb;
}
/* local processing follows */
if (!IPX_SKB_CB(skb)->ipx_dest_net)
IPX_SKB_CB(skb)->ipx_dest_net = intrfc->if_netnum;
if (!IPX_SKB_CB(skb)->ipx_source_net)
IPX_SKB_CB(skb)->ipx_source_net = intrfc->if_netnum;
/* it doesn't make sense to route a pprop packet, there's no meaning
* in the ipx_dest_net for such packets */
if (ipx->ipx_type != IPX_TYPE_PPROP &&
intrfc->if_netnum != IPX_SKB_CB(skb)->ipx_dest_net) {
/* We only route point-to-point packets. */
if (skb->pkt_type == PACKET_HOST) {
skb = skb_unshare(skb, GFP_ATOMIC);
if (skb)
rc = ipxrtr_route_skb(skb);
goto out_intrfc;
}
goto out_free_skb;
}
/* see if we should keep it */
if (!memcmp(ipx_broadcast_node, ipx->ipx_dest.node, IPX_NODE_LEN) ||
!memcmp(intrfc->if_node, ipx->ipx_dest.node, IPX_NODE_LEN)) {
rc = ipxitf_demux_socket(intrfc, skb, 0);
goto out_intrfc;
}
/* we couldn't pawn it off so unload it */
out_free_skb:
kfree_skb(skb);
out_intrfc:
ipxitf_put(intrfc);
return rc;
}
static void ipxitf_discover_netnum(struct ipx_interface *intrfc,
struct sk_buff *skb)
{
const struct ipx_cb *cb = IPX_SKB_CB(skb);
/* see if this is an intra packet: source_net == dest_net */
if (cb->ipx_source_net == cb->ipx_dest_net && cb->ipx_source_net) {
struct ipx_interface *i =
ipxitf_find_using_net(cb->ipx_source_net);
/* NB: NetWare servers lie about their hop count so we
* dropped the test based on it. This is the best way
* to determine this is a 0 hop count packet. */
if (!i) {
intrfc->if_netnum = cb->ipx_source_net;
ipxitf_add_local_route(intrfc);
} else {
net_warn_ratelimited("IPX: Network number collision "
"%lx\n %s %s and %s %s\n",
(unsigned long) ntohl(cb->ipx_source_net),
ipx_device_name(i),
ipx_frame_name(i->if_dlink_type),
ipx_device_name(intrfc),
ipx_frame_name(intrfc->if_dlink_type));
ipxitf_put(i);
}
}
}
/**
* ipxitf_pprop - Process packet propagation IPX packet type 0x14, used for
* NetBIOS broadcasts
* @intrfc: IPX interface receiving this packet
* @skb: Received packet
*
* Checks if packet is valid: if its more than %IPX_MAX_PPROP_HOPS hops or if it
* is smaller than a IPX header + the room for %IPX_MAX_PPROP_HOPS hops we drop
* it, not even processing it locally, if it has exact %IPX_MAX_PPROP_HOPS we
* don't broadcast it, but process it locally. See chapter 5 of Novell's "IPX
* RIP and SAP Router Specification", Part Number 107-000029-001.
*
* If it is valid, check if we have pprop broadcasting enabled by the user,
* if not, just return zero for local processing.
*
* If it is enabled check the packet and don't broadcast it if we have already
* seen this packet.
*
* Broadcast: send it to the interfaces that aren't on the packet visited nets
* array, just after the IPX header.
*
* Returns -EINVAL for invalid packets, so that the calling function drops
* the packet without local processing. 0 if packet is to be locally processed.
*/
static int ipxitf_pprop(struct ipx_interface *intrfc, struct sk_buff *skb)
{
struct ipxhdr *ipx = ipx_hdr(skb);
int i, rc = -EINVAL;
struct ipx_interface *ifcs;
char *c;
__be32 *l;
/* Illegal packet - too many hops or too short */
/* We decide to throw it away: no broadcasting, no local processing.
* NetBIOS unaware implementations route them as normal packets -
* tctrl <= 15, any data payload... */
if (IPX_SKB_CB(skb)->ipx_tctrl > IPX_MAX_PPROP_HOPS ||
ntohs(ipx->ipx_pktsize) < sizeof(struct ipxhdr) +
IPX_MAX_PPROP_HOPS * sizeof(u32))
goto out;
/* are we broadcasting this damn thing? */
rc = 0;
if (!sysctl_ipx_pprop_broadcasting)
goto out;
/* We do broadcast packet on the IPX_MAX_PPROP_HOPS hop, but we
* process it locally. All previous hops broadcasted it, and process it
* locally. */
if (IPX_SKB_CB(skb)->ipx_tctrl == IPX_MAX_PPROP_HOPS)
goto out;
c = ((u8 *) ipx) + sizeof(struct ipxhdr);
l = (__be32 *) c;
/* Don't broadcast packet if already seen this net */
for (i = 0; i < IPX_SKB_CB(skb)->ipx_tctrl; i++)
if (*l++ == intrfc->if_netnum)
goto out;
/* < IPX_MAX_PPROP_HOPS hops && input interface not in list. Save the
* position where we will insert recvd netnum into list, later on,
* in ipxitf_send */
IPX_SKB_CB(skb)->last_hop.index = i;
IPX_SKB_CB(skb)->last_hop.netnum = intrfc->if_netnum;
/* xmit on all other interfaces... */
spin_lock_bh(&ipx_interfaces_lock);
list_for_each_entry(ifcs, &ipx_interfaces, node) {
/* Except unconfigured interfaces */
if (!ifcs->if_netnum)
continue;
/* That aren't in the list */
if (ifcs == intrfc)
continue;
l = (__be32 *) c;
/* don't consider the last entry in the packet list,
* it is our netnum, and it is not there yet */
for (i = 0; i < IPX_SKB_CB(skb)->ipx_tctrl; i++)
if (ifcs->if_netnum == *l++)
break;
if (i == IPX_SKB_CB(skb)->ipx_tctrl) {
struct sk_buff *s = skb_copy(skb, GFP_ATOMIC);
if (s) {
IPX_SKB_CB(s)->ipx_dest_net = ifcs->if_netnum;
ipxrtr_route_skb(s);
}
}
}
spin_unlock_bh(&ipx_interfaces_lock);
out:
return rc;
}
static void ipxitf_insert(struct ipx_interface *intrfc)
{
spin_lock_bh(&ipx_interfaces_lock);
list_add_tail(&intrfc->node, &ipx_interfaces);
spin_unlock_bh(&ipx_interfaces_lock);
if (ipxcfg_auto_select_primary && !ipx_primary_net)
ipx_primary_net = intrfc;
}
static struct ipx_interface *ipxitf_alloc(struct net_device *dev, __be32 netnum,
__be16 dlink_type,
struct datalink_proto *dlink,
unsigned char internal,
int ipx_offset)
{
struct ipx_interface *intrfc = kmalloc(sizeof(*intrfc), GFP_ATOMIC);
if (intrfc) {
intrfc->if_dev = dev;
intrfc->if_netnum = netnum;
intrfc->if_dlink_type = dlink_type;
intrfc->if_dlink = dlink;
intrfc->if_internal = internal;
intrfc->if_ipx_offset = ipx_offset;
intrfc->if_sknum = IPX_MIN_EPHEMERAL_SOCKET;
INIT_HLIST_HEAD(&intrfc->if_sklist);
refcount_set(&intrfc->refcnt, 1);
spin_lock_init(&intrfc->if_sklist_lock);
}
return intrfc;
}
static int ipxitf_create_internal(struct ipx_interface_definition *idef)
{
struct ipx_interface *intrfc;
int rc = -EEXIST;
/* Only one primary network allowed */
if (ipx_primary_net)
goto out;
/* Must have a valid network number */
rc = -EADDRNOTAVAIL;
if (!idef->ipx_network)
goto out;
intrfc = ipxitf_find_using_net(idef->ipx_network);
rc = -EADDRINUSE;
if (intrfc) {
ipxitf_put(intrfc);
goto out;
}
intrfc = ipxitf_alloc(NULL, idef->ipx_network, 0, NULL, 1, 0);
rc = -EAGAIN;
if (!intrfc)
goto out;
memcpy((char *)&(intrfc->if_node), idef->ipx_node, IPX_NODE_LEN);
ipx_internal_net = ipx_primary_net = intrfc;
ipxitf_hold(intrfc);
ipxitf_insert(intrfc);
rc = ipxitf_add_local_route(intrfc);
ipxitf_put(intrfc);
out:
return rc;
}
static __be16 ipx_map_frame_type(unsigned char type)
{
__be16 rc = 0;
switch (type) {
case IPX_FRAME_ETHERII: rc = htons(ETH_P_IPX); break;
case IPX_FRAME_8022: rc = htons(ETH_P_802_2); break;
case IPX_FRAME_SNAP: rc = htons(ETH_P_SNAP); break;
case IPX_FRAME_8023: rc = htons(ETH_P_802_3); break;
}
return rc;
}
static int ipxitf_create(struct ipx_interface_definition *idef)
{
struct net_device *dev;
__be16 dlink_type = 0;
struct datalink_proto *datalink = NULL;
struct ipx_interface *intrfc;
int rc;
if (idef->ipx_special == IPX_INTERNAL) {
rc = ipxitf_create_internal(idef);
goto out;
}
rc = -EEXIST;
if (idef->ipx_special == IPX_PRIMARY && ipx_primary_net)
goto out;
intrfc = ipxitf_find_using_net(idef->ipx_network);
rc = -EADDRINUSE;
if (idef->ipx_network && intrfc) {
ipxitf_put(intrfc);
goto out;
}
if (intrfc)
ipxitf_put(intrfc);
dev = dev_get_by_name(&init_net, idef->ipx_device);
rc = -ENODEV;
if (!dev)
goto out;
switch (idef->ipx_dlink_type) {
case IPX_FRAME_8022:
dlink_type = htons(ETH_P_802_2);
datalink = p8022_datalink;
break;
case IPX_FRAME_ETHERII:
if (dev->type != ARPHRD_IEEE802) {
dlink_type = htons(ETH_P_IPX);
datalink = pEII_datalink;
break;
}
#if LINUX_VERSION_CODE >= KERNEL_VERSION(5,14,0)
fallthrough;
#endif
/* fallthrough */
case IPX_FRAME_SNAP:
dlink_type = htons(ETH_P_SNAP);
datalink = pSNAP_datalink;
break;
case IPX_FRAME_8023:
dlink_type = htons(ETH_P_802_3);
datalink = p8023_datalink;