forked from torvalds/linux
-
Notifications
You must be signed in to change notification settings - Fork 0
/
ipconfig.c
1692 lines (1446 loc) · 39.1 KB
/
ipconfig.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
/*
* Automatic Configuration of IP -- use DHCP, BOOTP, RARP, or
* user-supplied information to configure own IP address and routes.
*
* Copyright (C) 1996-1998 Martin Mares <[email protected]>
*
* Derived from network configuration code in fs/nfs/nfsroot.c,
* originally Copyright (C) 1995, 1996 Gero Kuhlmann and me.
*
* BOOTP rewritten to construct and analyse packets itself instead
* of misusing the IP layer. num_bugs_causing_wrong_arp_replies--;
* -- MJ, December 1998
*
* Fixed ip_auto_config_setup calling at startup in the new "Linker Magic"
* initialization scheme.
* - Arnaldo Carvalho de Melo <[email protected]>, 08/11/1999
*
* DHCP support added. To users this looks like a whole separate
* protocol, but we know it's just a bag on the side of BOOTP.
* -- Chip Salzenberg <[email protected]>, May 2000
*
* Ported DHCP support from 2.2.16 to 2.4.0-test4
* -- Eric Biederman <[email protected]>, 30 Aug 2000
*
* Merged changes from 2.2.19 into 2.4.3
* -- Eric Biederman <[email protected]>, 22 April Aug 2001
*
* Multiple Nameservers in /proc/net/pnp
* -- Josef Siemes <[email protected]>, Aug 2002
*/
#include <linux/types.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/jiffies.h>
#include <linux/random.h>
#include <linux/init.h>
#include <linux/utsname.h>
#include <linux/in.h>
#include <linux/if.h>
#include <linux/inet.h>
#include <linux/inetdevice.h>
#include <linux/netdevice.h>
#include <linux/if_arp.h>
#include <linux/skbuff.h>
#include <linux/ip.h>
#include <linux/socket.h>
#include <linux/route.h>
#include <linux/udp.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
#include <linux/major.h>
#include <linux/root_dev.h>
#include <linux/delay.h>
#include <linux/nfs_fs.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <net/net_namespace.h>
#include <net/arp.h>
#include <net/ip.h>
#include <net/ipconfig.h>
#include <net/route.h>
#include <asm/uaccess.h>
#include <net/checksum.h>
#include <asm/processor.h>
/* Define this to allow debugging output */
#undef IPCONFIG_DEBUG
#ifdef IPCONFIG_DEBUG
#define DBG(x) printk x
#else
#define DBG(x) do { } while(0)
#endif
#if defined(CONFIG_IP_PNP_DHCP)
#define IPCONFIG_DHCP
#endif
#if defined(CONFIG_IP_PNP_BOOTP) || defined(CONFIG_IP_PNP_DHCP)
#define IPCONFIG_BOOTP
#endif
#if defined(CONFIG_IP_PNP_RARP)
#define IPCONFIG_RARP
#endif
#if defined(IPCONFIG_BOOTP) || defined(IPCONFIG_RARP)
#define IPCONFIG_DYNAMIC
#endif
/* Define the friendly delay before and after opening net devices */
#define CONF_POST_OPEN 10 /* After opening: 10 msecs */
#define CONF_CARRIER_TIMEOUT 120000 /* Wait for carrier timeout */
/* Define the timeout for waiting for a DHCP/BOOTP/RARP reply */
#define CONF_OPEN_RETRIES 2 /* (Re)open devices twice */
#define CONF_SEND_RETRIES 6 /* Send six requests per open */
#define CONF_INTER_TIMEOUT (HZ/2) /* Inter-device timeout: 1/2 second */
#define CONF_BASE_TIMEOUT (HZ*2) /* Initial timeout: 2 seconds */
#define CONF_TIMEOUT_RANDOM (HZ) /* Maximum amount of randomization */
#define CONF_TIMEOUT_MULT *7/4 /* Rate of timeout growth */
#define CONF_TIMEOUT_MAX (HZ*30) /* Maximum allowed timeout */
#define CONF_NAMESERVERS_MAX 3 /* Maximum number of nameservers
- '3' from resolv.h */
#define NONE cpu_to_be32(INADDR_NONE)
#define ANY cpu_to_be32(INADDR_ANY)
/*
* Public IP configuration
*/
/* This is used by platforms which might be able to set the ipconfig
* variables using firmware environment vars. If this is set, it will
* ignore such firmware variables.
*/
int ic_set_manually __initdata = 0; /* IPconfig parameters set manually */
static int ic_enable __initdata = 0; /* IP config enabled? */
/* Protocol choice */
int ic_proto_enabled __initdata = 0
#ifdef IPCONFIG_BOOTP
| IC_BOOTP
#endif
#ifdef CONFIG_IP_PNP_DHCP
| IC_USE_DHCP
#endif
#ifdef IPCONFIG_RARP
| IC_RARP
#endif
;
static int ic_host_name_set __initdata = 0; /* Host name set by us? */
__be32 ic_myaddr = NONE; /* My IP address */
static __be32 ic_netmask = NONE; /* Netmask for local subnet */
__be32 ic_gateway = NONE; /* Gateway IP address */
__be32 ic_addrservaddr = NONE; /* IP Address of the IP addresses'server */
__be32 ic_servaddr = NONE; /* Boot server IP address */
__be32 root_server_addr = NONE; /* Address of NFS server */
u8 root_server_path[256] = { 0, }; /* Path to mount as root */
/* vendor class identifier */
static char vendor_class_identifier[253] __initdata;
/* Persistent data: */
static int ic_proto_used; /* Protocol used, if any */
static __be32 ic_nameservers[CONF_NAMESERVERS_MAX]; /* DNS Server IP addresses */
static u8 ic_domain[64]; /* DNS (not NIS) domain name */
/*
* Private state.
*/
/* Name of user-selected boot device */
static char user_dev_name[IFNAMSIZ] __initdata = { 0, };
/* Protocols supported by available interfaces */
static int ic_proto_have_if __initdata = 0;
/* MTU for boot device */
static int ic_dev_mtu __initdata = 0;
#ifdef IPCONFIG_DYNAMIC
static DEFINE_SPINLOCK(ic_recv_lock);
static volatile int ic_got_reply __initdata = 0; /* Proto(s) that replied */
#endif
#ifdef IPCONFIG_DHCP
static int ic_dhcp_msgtype __initdata = 0; /* DHCP msg type received */
#endif
/*
* Network devices
*/
struct ic_device {
struct ic_device *next;
struct net_device *dev;
unsigned short flags;
short able;
__be32 xid;
};
static struct ic_device *ic_first_dev __initdata = NULL;/* List of open device */
static struct net_device *ic_dev __initdata = NULL; /* Selected device */
static bool __init ic_is_init_dev(struct net_device *dev)
{
if (dev->flags & IFF_LOOPBACK)
return false;
return user_dev_name[0] ? !strcmp(dev->name, user_dev_name) :
(!(dev->flags & IFF_LOOPBACK) &&
(dev->flags & (IFF_POINTOPOINT|IFF_BROADCAST)) &&
strncmp(dev->name, "dummy", 5));
}
static int __init ic_open_devs(void)
{
struct ic_device *d, **last;
struct net_device *dev;
unsigned short oflags;
unsigned long start, next_msg;
last = &ic_first_dev;
rtnl_lock();
/* bring loopback device up first */
for_each_netdev(&init_net, dev) {
if (!(dev->flags & IFF_LOOPBACK))
continue;
if (dev_change_flags(dev, dev->flags | IFF_UP) < 0)
pr_err("IP-Config: Failed to open %s\n", dev->name);
}
for_each_netdev(&init_net, dev) {
if (ic_is_init_dev(dev)) {
int able = 0;
if (dev->mtu >= 364)
able |= IC_BOOTP;
else
pr_warn("DHCP/BOOTP: Ignoring device %s, MTU %d too small",
dev->name, dev->mtu);
if (!(dev->flags & IFF_NOARP))
able |= IC_RARP;
able &= ic_proto_enabled;
if (ic_proto_enabled && !able)
continue;
oflags = dev->flags;
if (dev_change_flags(dev, oflags | IFF_UP) < 0) {
pr_err("IP-Config: Failed to open %s\n",
dev->name);
continue;
}
if (!(d = kmalloc(sizeof(struct ic_device), GFP_KERNEL))) {
rtnl_unlock();
return -ENOMEM;
}
d->dev = dev;
*last = d;
last = &d->next;
d->flags = oflags;
d->able = able;
if (able & IC_BOOTP)
get_random_bytes(&d->xid, sizeof(__be32));
else
d->xid = 0;
ic_proto_have_if |= able;
DBG(("IP-Config: %s UP (able=%d, xid=%08x)\n",
dev->name, able, d->xid));
}
}
/* no point in waiting if we could not bring up at least one device */
if (!ic_first_dev)
goto have_carrier;
/* wait for a carrier on at least one device */
start = jiffies;
next_msg = start + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
while (time_before(jiffies, start +
msecs_to_jiffies(CONF_CARRIER_TIMEOUT))) {
int wait, elapsed;
for_each_netdev(&init_net, dev)
if (ic_is_init_dev(dev) && netif_carrier_ok(dev))
goto have_carrier;
msleep(1);
if (time_before(jiffies, next_msg))
continue;
elapsed = jiffies_to_msecs(jiffies - start);
wait = (CONF_CARRIER_TIMEOUT - elapsed + 500)/1000;
pr_info("Waiting up to %d more seconds for network.\n", wait);
next_msg = jiffies + msecs_to_jiffies(CONF_CARRIER_TIMEOUT/12);
}
have_carrier:
rtnl_unlock();
*last = NULL;
if (!ic_first_dev) {
if (user_dev_name[0])
pr_err("IP-Config: Device `%s' not found\n",
user_dev_name);
else
pr_err("IP-Config: No network devices available\n");
return -ENODEV;
}
return 0;
}
static void __init ic_close_devs(void)
{
struct ic_device *d, *next;
struct net_device *dev;
rtnl_lock();
next = ic_first_dev;
while ((d = next)) {
next = d->next;
dev = d->dev;
if (dev != ic_dev) {
DBG(("IP-Config: Downing %s\n", dev->name));
dev_change_flags(dev, d->flags);
}
kfree(d);
}
rtnl_unlock();
}
/*
* Interface to various network functions.
*/
static inline void
set_sockaddr(struct sockaddr_in *sin, __be32 addr, __be16 port)
{
sin->sin_family = AF_INET;
sin->sin_addr.s_addr = addr;
sin->sin_port = port;
}
static int __init ic_devinet_ioctl(unsigned int cmd, struct ifreq *arg)
{
int res;
mm_segment_t oldfs = get_fs();
set_fs(get_ds());
res = devinet_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
set_fs(oldfs);
return res;
}
static int __init ic_dev_ioctl(unsigned int cmd, struct ifreq *arg)
{
int res;
mm_segment_t oldfs = get_fs();
set_fs(get_ds());
res = dev_ioctl(&init_net, cmd, (struct ifreq __user *) arg);
set_fs(oldfs);
return res;
}
static int __init ic_route_ioctl(unsigned int cmd, struct rtentry *arg)
{
int res;
mm_segment_t oldfs = get_fs();
set_fs(get_ds());
res = ip_rt_ioctl(&init_net, cmd, (void __user *) arg);
set_fs(oldfs);
return res;
}
/*
* Set up interface addresses and routes.
*/
static int __init ic_setup_if(void)
{
struct ifreq ir;
struct sockaddr_in *sin = (void *) &ir.ifr_ifru.ifru_addr;
int err;
memset(&ir, 0, sizeof(ir));
strcpy(ir.ifr_ifrn.ifrn_name, ic_dev->name);
set_sockaddr(sin, ic_myaddr, 0);
if ((err = ic_devinet_ioctl(SIOCSIFADDR, &ir)) < 0) {
pr_err("IP-Config: Unable to set interface address (%d)\n",
err);
return -1;
}
set_sockaddr(sin, ic_netmask, 0);
if ((err = ic_devinet_ioctl(SIOCSIFNETMASK, &ir)) < 0) {
pr_err("IP-Config: Unable to set interface netmask (%d)\n",
err);
return -1;
}
set_sockaddr(sin, ic_myaddr | ~ic_netmask, 0);
if ((err = ic_devinet_ioctl(SIOCSIFBRDADDR, &ir)) < 0) {
pr_err("IP-Config: Unable to set interface broadcast address (%d)\n",
err);
return -1;
}
/* Handle the case where we need non-standard MTU on the boot link (a network
* using jumbo frames, for instance). If we can't set the mtu, don't error
* out, we'll try to muddle along.
*/
if (ic_dev_mtu != 0) {
strcpy(ir.ifr_name, ic_dev->name);
ir.ifr_mtu = ic_dev_mtu;
if ((err = ic_dev_ioctl(SIOCSIFMTU, &ir)) < 0)
pr_err("IP-Config: Unable to set interface mtu to %d (%d)\n",
ic_dev_mtu, err);
}
return 0;
}
static int __init ic_setup_routes(void)
{
/* No need to setup device routes, only the default route... */
if (ic_gateway != NONE) {
struct rtentry rm;
int err;
memset(&rm, 0, sizeof(rm));
if ((ic_gateway ^ ic_myaddr) & ic_netmask) {
pr_err("IP-Config: Gateway not on directly connected network\n");
return -1;
}
set_sockaddr((struct sockaddr_in *) &rm.rt_dst, 0, 0);
set_sockaddr((struct sockaddr_in *) &rm.rt_genmask, 0, 0);
set_sockaddr((struct sockaddr_in *) &rm.rt_gateway, ic_gateway, 0);
rm.rt_flags = RTF_UP | RTF_GATEWAY;
if ((err = ic_route_ioctl(SIOCADDRT, &rm)) < 0) {
pr_err("IP-Config: Cannot add default route (%d)\n",
err);
return -1;
}
}
return 0;
}
/*
* Fill in default values for all missing parameters.
*/
static int __init ic_defaults(void)
{
/*
* At this point we have no userspace running so need not
* claim locks on system_utsname
*/
if (!ic_host_name_set)
sprintf(init_utsname()->nodename, "%pI4", &ic_myaddr);
if (root_server_addr == NONE)
root_server_addr = ic_servaddr;
if (ic_netmask == NONE) {
if (IN_CLASSA(ntohl(ic_myaddr)))
ic_netmask = htonl(IN_CLASSA_NET);
else if (IN_CLASSB(ntohl(ic_myaddr)))
ic_netmask = htonl(IN_CLASSB_NET);
else if (IN_CLASSC(ntohl(ic_myaddr)))
ic_netmask = htonl(IN_CLASSC_NET);
else {
pr_err("IP-Config: Unable to guess netmask for address %pI4\n",
&ic_myaddr);
return -1;
}
printk("IP-Config: Guessing netmask %pI4\n", &ic_netmask);
}
return 0;
}
/*
* RARP support.
*/
#ifdef IPCONFIG_RARP
static int ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
static struct packet_type rarp_packet_type __initdata = {
.type = cpu_to_be16(ETH_P_RARP),
.func = ic_rarp_recv,
};
static inline void __init ic_rarp_init(void)
{
dev_add_pack(&rarp_packet_type);
}
static inline void __init ic_rarp_cleanup(void)
{
dev_remove_pack(&rarp_packet_type);
}
/*
* Process received RARP packet.
*/
static int __init
ic_rarp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
{
struct arphdr *rarp;
unsigned char *rarp_ptr;
__be32 sip, tip;
unsigned char *sha, *tha; /* s for "source", t for "target" */
struct ic_device *d;
if (!net_eq(dev_net(dev), &init_net))
goto drop;
if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
return NET_RX_DROP;
if (!pskb_may_pull(skb, sizeof(struct arphdr)))
goto drop;
/* Basic sanity checks can be done without the lock. */
rarp = (struct arphdr *)skb_transport_header(skb);
/* If this test doesn't pass, it's not IP, or we should
* ignore it anyway.
*/
if (rarp->ar_hln != dev->addr_len || dev->type != ntohs(rarp->ar_hrd))
goto drop;
/* If it's not a RARP reply, delete it. */
if (rarp->ar_op != htons(ARPOP_RREPLY))
goto drop;
/* If it's not Ethernet, delete it. */
if (rarp->ar_pro != htons(ETH_P_IP))
goto drop;
if (!pskb_may_pull(skb, arp_hdr_len(dev)))
goto drop;
/* OK, it is all there and looks valid, process... */
rarp = (struct arphdr *)skb_transport_header(skb);
rarp_ptr = (unsigned char *) (rarp + 1);
/* One reply at a time, please. */
spin_lock(&ic_recv_lock);
/* If we already have a reply, just drop the packet */
if (ic_got_reply)
goto drop_unlock;
/* Find the ic_device that the packet arrived on */
d = ic_first_dev;
while (d && d->dev != dev)
d = d->next;
if (!d)
goto drop_unlock; /* should never happen */
/* Extract variable-width fields */
sha = rarp_ptr;
rarp_ptr += dev->addr_len;
memcpy(&sip, rarp_ptr, 4);
rarp_ptr += 4;
tha = rarp_ptr;
rarp_ptr += dev->addr_len;
memcpy(&tip, rarp_ptr, 4);
/* Discard packets which are not meant for us. */
if (memcmp(tha, dev->dev_addr, dev->addr_len))
goto drop_unlock;
/* Discard packets which are not from specified server. */
if (ic_servaddr != NONE && ic_servaddr != sip)
goto drop_unlock;
/* We have a winner! */
ic_dev = dev;
if (ic_myaddr == NONE)
ic_myaddr = tip;
ic_servaddr = sip;
ic_addrservaddr = sip;
ic_got_reply = IC_RARP;
drop_unlock:
/* Show's over. Nothing to see here. */
spin_unlock(&ic_recv_lock);
drop:
/* Throw the packet out. */
kfree_skb(skb);
return 0;
}
/*
* Send RARP request packet over a single interface.
*/
static void __init ic_rarp_send_if(struct ic_device *d)
{
struct net_device *dev = d->dev;
arp_send(ARPOP_RREQUEST, ETH_P_RARP, 0, dev, 0, NULL,
dev->dev_addr, dev->dev_addr);
}
#endif
/*
* Predefine Nameservers
*/
static inline void __init ic_nameservers_predef(void)
{
int i;
for (i = 0; i < CONF_NAMESERVERS_MAX; i++)
ic_nameservers[i] = NONE;
}
/*
* DHCP/BOOTP support.
*/
#ifdef IPCONFIG_BOOTP
struct bootp_pkt { /* BOOTP packet format */
struct iphdr iph; /* IP header */
struct udphdr udph; /* UDP header */
u8 op; /* 1=request, 2=reply */
u8 htype; /* HW address type */
u8 hlen; /* HW address length */
u8 hops; /* Used only by gateways */
__be32 xid; /* Transaction ID */
__be16 secs; /* Seconds since we started */
__be16 flags; /* Just what it says */
__be32 client_ip; /* Client's IP address if known */
__be32 your_ip; /* Assigned IP address */
__be32 server_ip; /* (Next, e.g. NFS) Server's IP address */
__be32 relay_ip; /* IP address of BOOTP relay */
u8 hw_addr[16]; /* Client's HW address */
u8 serv_name[64]; /* Server host name */
u8 boot_file[128]; /* Name of boot file */
u8 exten[312]; /* DHCP options / BOOTP vendor extensions */
};
/* packet ops */
#define BOOTP_REQUEST 1
#define BOOTP_REPLY 2
/* DHCP message types */
#define DHCPDISCOVER 1
#define DHCPOFFER 2
#define DHCPREQUEST 3
#define DHCPDECLINE 4
#define DHCPACK 5
#define DHCPNAK 6
#define DHCPRELEASE 7
#define DHCPINFORM 8
static int ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev);
static struct packet_type bootp_packet_type __initdata = {
.type = cpu_to_be16(ETH_P_IP),
.func = ic_bootp_recv,
};
static __be32 ic_dev_xid; /* Device under configuration */
/*
* Initialize DHCP/BOOTP extension fields in the request.
*/
static const u8 ic_bootp_cookie[4] = { 99, 130, 83, 99 };
#ifdef IPCONFIG_DHCP
static void __init
ic_dhcp_init_options(u8 *options)
{
u8 mt = ((ic_servaddr == NONE)
? DHCPDISCOVER : DHCPREQUEST);
u8 *e = options;
int len;
#ifdef IPCONFIG_DEBUG
printk("DHCP: Sending message type %d\n", mt);
#endif
memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
e += 4;
*e++ = 53; /* DHCP message type */
*e++ = 1;
*e++ = mt;
if (mt == DHCPREQUEST) {
*e++ = 54; /* Server ID (IP address) */
*e++ = 4;
memcpy(e, &ic_servaddr, 4);
e += 4;
*e++ = 50; /* Requested IP address */
*e++ = 4;
memcpy(e, &ic_myaddr, 4);
e += 4;
}
/* always? */
{
static const u8 ic_req_params[] = {
1, /* Subnet mask */
3, /* Default gateway */
6, /* DNS server */
12, /* Host name */
15, /* Domain name */
17, /* Boot path */
26, /* MTU */
40, /* NIS domain name */
};
*e++ = 55; /* Parameter request list */
*e++ = sizeof(ic_req_params);
memcpy(e, ic_req_params, sizeof(ic_req_params));
e += sizeof(ic_req_params);
if (ic_host_name_set) {
*e++ = 12; /* host-name */
len = strlen(utsname()->nodename);
*e++ = len;
memcpy(e, utsname()->nodename, len);
e += len;
}
if (*vendor_class_identifier) {
pr_info("DHCP: sending class identifier \"%s\"\n",
vendor_class_identifier);
*e++ = 60; /* Class-identifier */
len = strlen(vendor_class_identifier);
*e++ = len;
memcpy(e, vendor_class_identifier, len);
e += len;
}
}
*e++ = 255; /* End of the list */
}
#endif /* IPCONFIG_DHCP */
static void __init ic_bootp_init_ext(u8 *e)
{
memcpy(e, ic_bootp_cookie, 4); /* RFC1048 Magic Cookie */
e += 4;
*e++ = 1; /* Subnet mask request */
*e++ = 4;
e += 4;
*e++ = 3; /* Default gateway request */
*e++ = 4;
e += 4;
*e++ = 5; /* Name server request */
*e++ = 8;
e += 8;
*e++ = 12; /* Host name request */
*e++ = 32;
e += 32;
*e++ = 40; /* NIS Domain name request */
*e++ = 32;
e += 32;
*e++ = 17; /* Boot path */
*e++ = 40;
e += 40;
*e++ = 57; /* set extension buffer size for reply */
*e++ = 2;
*e++ = 1; /* 128+236+8+20+14, see dhcpd sources */
*e++ = 150;
*e++ = 255; /* End of the list */
}
/*
* Initialize the DHCP/BOOTP mechanism.
*/
static inline void __init ic_bootp_init(void)
{
ic_nameservers_predef();
dev_add_pack(&bootp_packet_type);
}
/*
* DHCP/BOOTP cleanup.
*/
static inline void __init ic_bootp_cleanup(void)
{
dev_remove_pack(&bootp_packet_type);
}
/*
* Send DHCP/BOOTP request to single interface.
*/
static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_diff)
{
struct net_device *dev = d->dev;
struct sk_buff *skb;
struct bootp_pkt *b;
struct iphdr *h;
int hlen = LL_RESERVED_SPACE(dev);
int tlen = dev->needed_tailroom;
/* Allocate packet */
skb = alloc_skb(sizeof(struct bootp_pkt) + hlen + tlen + 15,
GFP_KERNEL);
if (!skb)
return;
skb_reserve(skb, hlen);
b = (struct bootp_pkt *) skb_put(skb, sizeof(struct bootp_pkt));
memset(b, 0, sizeof(struct bootp_pkt));
/* Construct IP header */
skb_reset_network_header(skb);
h = ip_hdr(skb);
h->version = 4;
h->ihl = 5;
h->tot_len = htons(sizeof(struct bootp_pkt));
h->frag_off = htons(IP_DF);
h->ttl = 64;
h->protocol = IPPROTO_UDP;
h->daddr = htonl(INADDR_BROADCAST);
h->check = ip_fast_csum((unsigned char *) h, h->ihl);
/* Construct UDP header */
b->udph.source = htons(68);
b->udph.dest = htons(67);
b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
/* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
/* Construct DHCP/BOOTP header */
b->op = BOOTP_REQUEST;
if (dev->type < 256) /* check for false types */
b->htype = dev->type;
else if (dev->type == ARPHRD_FDDI)
b->htype = ARPHRD_ETHER;
else {
printk("Unknown ARP type 0x%04x for device %s\n", dev->type, dev->name);
b->htype = dev->type; /* can cause undefined behavior */
}
/* server_ip and your_ip address are both already zero per RFC2131 */
b->hlen = dev->addr_len;
memcpy(b->hw_addr, dev->dev_addr, dev->addr_len);
b->secs = htons(jiffies_diff / HZ);
b->xid = d->xid;
/* add DHCP options or BOOTP extensions */
#ifdef IPCONFIG_DHCP
if (ic_proto_enabled & IC_USE_DHCP)
ic_dhcp_init_options(b->exten);
else
#endif
ic_bootp_init_ext(b->exten);
/* Chain packet down the line... */
skb->dev = dev;
skb->protocol = htons(ETH_P_IP);
if (dev_hard_header(skb, dev, ntohs(skb->protocol),
dev->broadcast, dev->dev_addr, skb->len) < 0) {
kfree_skb(skb);
printk("E");
return;
}
if (dev_queue_xmit(skb) < 0)
printk("E");
}
/*
* Copy BOOTP-supplied string if not already set.
*/
static int __init ic_bootp_string(char *dest, char *src, int len, int max)
{
if (!len)
return 0;
if (len > max-1)
len = max-1;
memcpy(dest, src, len);
dest[len] = '\0';
return 1;
}
/*
* Process BOOTP extensions.
*/
static void __init ic_do_bootp_ext(u8 *ext)
{
u8 servers;
int i;
__be16 mtu;
#ifdef IPCONFIG_DEBUG
u8 *c;
printk("DHCP/BOOTP: Got extension %d:",*ext);
for (c=ext+2; c<ext+2+ext[1]; c++)
printk(" %02x", *c);
printk("\n");
#endif
switch (*ext++) {
case 1: /* Subnet mask */
if (ic_netmask == NONE)
memcpy(&ic_netmask, ext+1, 4);
break;
case 3: /* Default gateway */
if (ic_gateway == NONE)
memcpy(&ic_gateway, ext+1, 4);
break;
case 6: /* DNS server */
servers= *ext/4;
if (servers > CONF_NAMESERVERS_MAX)
servers = CONF_NAMESERVERS_MAX;
for (i = 0; i < servers; i++) {
if (ic_nameservers[i] == NONE)
memcpy(&ic_nameservers[i], ext+1+4*i, 4);
}
break;
case 12: /* Host name */
ic_bootp_string(utsname()->nodename, ext+1, *ext,
__NEW_UTS_LEN);
ic_host_name_set = 1;
break;
case 15: /* Domain name (DNS) */
ic_bootp_string(ic_domain, ext+1, *ext, sizeof(ic_domain));
break;
case 17: /* Root path */
if (!root_server_path[0])
ic_bootp_string(root_server_path, ext+1, *ext,
sizeof(root_server_path));
break;
case 26: /* Interface MTU */
memcpy(&mtu, ext+1, sizeof(mtu));
ic_dev_mtu = ntohs(mtu);
break;
case 40: /* NIS Domain name (_not_ DNS) */
ic_bootp_string(utsname()->domainname, ext+1, *ext,
__NEW_UTS_LEN);
break;
}
}
/*
* Receive BOOTP reply.
*/
static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
{
struct bootp_pkt *b;
struct iphdr *h;
struct ic_device *d;
int len, ext_len;
if (!net_eq(dev_net(dev), &init_net))
goto drop;
/* Perform verifications before taking the lock. */
if (skb->pkt_type == PACKET_OTHERHOST)
goto drop;
if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
return NET_RX_DROP;
if (!pskb_may_pull(skb,
sizeof(struct iphdr) +
sizeof(struct udphdr)))
goto drop;
b = (struct bootp_pkt *)skb_network_header(skb);
h = &b->iph;
if (h->ihl != 5 || h->version != 4 || h->protocol != IPPROTO_UDP)
goto drop;
/* Fragments are not supported */
if (ip_is_fragment(h)) {
net_err_ratelimited("DHCP/BOOTP: Ignoring fragmented reply\n");
goto drop;
}
if (skb->len < ntohs(h->tot_len))
goto drop;
if (ip_fast_csum((char *) h, h->ihl))
goto drop;
if (b->udph.source != htons(67) || b->udph.dest != htons(68))
goto drop;
if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
goto drop;
len = ntohs(b->udph.len) - sizeof(struct udphdr);
ext_len = len - (sizeof(*b) -
sizeof(struct iphdr) -
sizeof(struct udphdr) -
sizeof(b->exten));
if (ext_len < 0)
goto drop;