forked from torvalds/linux
-
Notifications
You must be signed in to change notification settings - Fork 0
/
smackfs.c
1369 lines (1161 loc) · 30.4 KB
/
smackfs.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
/*
* Copyright (C) 2007 Casey Schaufler <[email protected]>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, version 2.
*
* Authors:
* Casey Schaufler <[email protected]>
* Ahmed S. Darwish <[email protected]>
*
* Special thanks to the authors of selinuxfs.
*
* Karl MacMillan <[email protected]>
* James Morris <[email protected]>
*
*/
#include <linux/kernel.h>
#include <linux/vmalloc.h>
#include <linux/security.h>
#include <linux/mutex.h>
#include <net/net_namespace.h>
#include <net/netlabel.h>
#include <net/cipso_ipv4.h>
#include <linux/seq_file.h>
#include <linux/ctype.h>
#include <linux/audit.h>
#include "smack.h"
/*
* smackfs pseudo filesystem.
*/
enum smk_inos {
SMK_ROOT_INO = 2,
SMK_LOAD = 3, /* load policy */
SMK_CIPSO = 4, /* load label -> CIPSO mapping */
SMK_DOI = 5, /* CIPSO DOI */
SMK_DIRECT = 6, /* CIPSO level indicating direct label */
SMK_AMBIENT = 7, /* internet ambient label */
SMK_NETLBLADDR = 8, /* single label hosts */
SMK_ONLYCAP = 9, /* the only "capable" label */
SMK_LOGGING = 10, /* logging */
};
/*
* List locks
*/
static DEFINE_MUTEX(smack_list_lock);
static DEFINE_MUTEX(smack_cipso_lock);
static DEFINE_MUTEX(smack_ambient_lock);
static DEFINE_MUTEX(smk_netlbladdr_lock);
/*
* This is the "ambient" label for network traffic.
* If it isn't somehow marked, use this.
* It can be reset via smackfs/ambient
*/
char *smack_net_ambient = smack_known_floor.smk_known;
/*
* This is the level in a CIPSO header that indicates a
* smack label is contained directly in the category set.
* It can be reset via smackfs/direct
*/
int smack_cipso_direct = SMACK_CIPSO_DIRECT_DEFAULT;
/*
* Unless a process is running with this label even
* having CAP_MAC_OVERRIDE isn't enough to grant
* privilege to violate MAC policy. If no label is
* designated (the NULL case) capabilities apply to
* everyone. It is expected that the hat (^) label
* will be used if any label is used.
*/
char *smack_onlycap;
/*
* Certain IP addresses may be designated as single label hosts.
* Packets are sent there unlabeled, but only from tasks that
* can write to the specified label.
*/
LIST_HEAD(smk_netlbladdr_list);
LIST_HEAD(smack_rule_list);
static int smk_cipso_doi_value = SMACK_CIPSO_DOI_DEFAULT;
const char *smack_cipso_option = SMACK_CIPSO_OPTION;
#define SEQ_READ_FINISHED 1
/*
* Values for parsing cipso rules
* SMK_DIGITLEN: Length of a digit field in a rule.
* SMK_CIPSOMIN: Minimum possible cipso rule length.
* SMK_CIPSOMAX: Maximum possible cipso rule length.
*/
#define SMK_DIGITLEN 4
#define SMK_CIPSOMIN (SMK_LABELLEN + 2 * SMK_DIGITLEN)
#define SMK_CIPSOMAX (SMK_CIPSOMIN + SMACK_CIPSO_MAXCATNUM * SMK_DIGITLEN)
/*
* Values for parsing MAC rules
* SMK_ACCESS: Maximum possible combination of access permissions
* SMK_ACCESSLEN: Maximum length for a rule access field
* SMK_LOADLEN: Smack rule length
*/
#define SMK_ACCESS "rwxa"
#define SMK_ACCESSLEN (sizeof(SMK_ACCESS) - 1)
#define SMK_LOADLEN (SMK_LABELLEN + SMK_LABELLEN + SMK_ACCESSLEN)
/**
* smk_netlabel_audit_set - fill a netlbl_audit struct
* @nap: structure to fill
*/
static void smk_netlabel_audit_set(struct netlbl_audit *nap)
{
nap->loginuid = audit_get_loginuid(current);
nap->sessionid = audit_get_sessionid(current);
nap->secid = smack_to_secid(current_security());
}
/*
* Values for parsing single label host rules
* "1.2.3.4 X"
* "192.168.138.129/32 abcdefghijklmnopqrstuvw"
*/
#define SMK_NETLBLADDRMIN 9
#define SMK_NETLBLADDRMAX 42
/*
* Seq_file read operations for /smack/load
*/
static void *load_seq_start(struct seq_file *s, loff_t *pos)
{
if (*pos == SEQ_READ_FINISHED)
return NULL;
if (list_empty(&smack_rule_list))
return NULL;
return smack_rule_list.next;
}
static void *load_seq_next(struct seq_file *s, void *v, loff_t *pos)
{
struct list_head *list = v;
if (list_is_last(list, &smack_rule_list)) {
*pos = SEQ_READ_FINISHED;
return NULL;
}
return list->next;
}
static int load_seq_show(struct seq_file *s, void *v)
{
struct list_head *list = v;
struct smack_rule *srp =
list_entry(list, struct smack_rule, list);
seq_printf(s, "%s %s", (char *)srp->smk_subject,
(char *)srp->smk_object);
seq_putc(s, ' ');
if (srp->smk_access & MAY_READ)
seq_putc(s, 'r');
if (srp->smk_access & MAY_WRITE)
seq_putc(s, 'w');
if (srp->smk_access & MAY_EXEC)
seq_putc(s, 'x');
if (srp->smk_access & MAY_APPEND)
seq_putc(s, 'a');
if (srp->smk_access == 0)
seq_putc(s, '-');
seq_putc(s, '\n');
return 0;
}
static void load_seq_stop(struct seq_file *s, void *v)
{
/* No-op */
}
static const struct seq_operations load_seq_ops = {
.start = load_seq_start,
.next = load_seq_next,
.show = load_seq_show,
.stop = load_seq_stop,
};
/**
* smk_open_load - open() for /smack/load
* @inode: inode structure representing file
* @file: "load" file pointer
*
* For reading, use load_seq_* seq_file reading operations.
*/
static int smk_open_load(struct inode *inode, struct file *file)
{
return seq_open(file, &load_seq_ops);
}
/**
* smk_set_access - add a rule to the rule list
* @srp: the new rule to add
*
* Looks through the current subject/object/access list for
* the subject/object pair and replaces the access that was
* there. If the pair isn't found add it with the specified
* access.
*
* Returns 0 if nothing goes wrong or -ENOMEM if it fails
* during the allocation of the new pair to add.
*/
static int smk_set_access(struct smack_rule *srp)
{
struct smack_rule *sp;
int ret = 0;
int found;
mutex_lock(&smack_list_lock);
found = 0;
list_for_each_entry_rcu(sp, &smack_rule_list, list) {
if (sp->smk_subject == srp->smk_subject &&
sp->smk_object == srp->smk_object) {
found = 1;
sp->smk_access = srp->smk_access;
break;
}
}
if (found == 0)
list_add_rcu(&srp->list, &smack_rule_list);
mutex_unlock(&smack_list_lock);
return ret;
}
/**
* smk_write_load - write() for /smack/load
* @file: file pointer, not actually used
* @buf: where to get the data from
* @count: bytes sent
* @ppos: where to start - must be 0
*
* Get one smack access rule from above.
* The format is exactly:
* char subject[SMK_LABELLEN]
* char object[SMK_LABELLEN]
* char access[SMK_ACCESSLEN]
*
* writes must be SMK_LABELLEN+SMK_LABELLEN+SMK_ACCESSLEN bytes.
*/
static ssize_t smk_write_load(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct smack_rule *rule;
char *data;
int rc = -EINVAL;
/*
* Must have privilege.
* No partial writes.
* Enough data must be present.
*/
if (!capable(CAP_MAC_ADMIN))
return -EPERM;
if (*ppos != 0 || count != SMK_LOADLEN)
return -EINVAL;
data = kzalloc(count, GFP_KERNEL);
if (data == NULL)
return -ENOMEM;
if (copy_from_user(data, buf, count) != 0) {
rc = -EFAULT;
goto out;
}
rule = kzalloc(sizeof(*rule), GFP_KERNEL);
if (rule == NULL) {
rc = -ENOMEM;
goto out;
}
rule->smk_subject = smk_import(data, 0);
if (rule->smk_subject == NULL)
goto out_free_rule;
rule->smk_object = smk_import(data + SMK_LABELLEN, 0);
if (rule->smk_object == NULL)
goto out_free_rule;
rule->smk_access = 0;
switch (data[SMK_LABELLEN + SMK_LABELLEN]) {
case '-':
break;
case 'r':
case 'R':
rule->smk_access |= MAY_READ;
break;
default:
goto out_free_rule;
}
switch (data[SMK_LABELLEN + SMK_LABELLEN + 1]) {
case '-':
break;
case 'w':
case 'W':
rule->smk_access |= MAY_WRITE;
break;
default:
goto out_free_rule;
}
switch (data[SMK_LABELLEN + SMK_LABELLEN + 2]) {
case '-':
break;
case 'x':
case 'X':
rule->smk_access |= MAY_EXEC;
break;
default:
goto out_free_rule;
}
switch (data[SMK_LABELLEN + SMK_LABELLEN + 3]) {
case '-':
break;
case 'a':
case 'A':
rule->smk_access |= MAY_APPEND;
break;
default:
goto out_free_rule;
}
rc = smk_set_access(rule);
if (!rc)
rc = count;
goto out;
out_free_rule:
kfree(rule);
out:
kfree(data);
return rc;
}
static const struct file_operations smk_load_ops = {
.open = smk_open_load,
.read = seq_read,
.llseek = seq_lseek,
.write = smk_write_load,
.release = seq_release,
};
/**
* smk_cipso_doi - initialize the CIPSO domain
*/
static void smk_cipso_doi(void)
{
int rc;
struct cipso_v4_doi *doip;
struct netlbl_audit nai;
smk_netlabel_audit_set(&nai);
rc = netlbl_cfg_map_del(NULL, PF_INET, NULL, NULL, &nai);
if (rc != 0)
printk(KERN_WARNING "%s:%d remove rc = %d\n",
__func__, __LINE__, rc);
doip = kmalloc(sizeof(struct cipso_v4_doi), GFP_KERNEL);
if (doip == NULL)
panic("smack: Failed to initialize cipso DOI.\n");
doip->map.std = NULL;
doip->doi = smk_cipso_doi_value;
doip->type = CIPSO_V4_MAP_PASS;
doip->tags[0] = CIPSO_V4_TAG_RBITMAP;
for (rc = 1; rc < CIPSO_V4_TAG_MAXCNT; rc++)
doip->tags[rc] = CIPSO_V4_TAG_INVALID;
rc = netlbl_cfg_cipsov4_add(doip, &nai);
if (rc != 0) {
printk(KERN_WARNING "%s:%d cipso add rc = %d\n",
__func__, __LINE__, rc);
kfree(doip);
return;
}
rc = netlbl_cfg_cipsov4_map_add(doip->doi, NULL, NULL, NULL, &nai);
if (rc != 0) {
printk(KERN_WARNING "%s:%d map add rc = %d\n",
__func__, __LINE__, rc);
kfree(doip);
return;
}
}
/**
* smk_unlbl_ambient - initialize the unlabeled domain
* @oldambient: previous domain string
*/
static void smk_unlbl_ambient(char *oldambient)
{
int rc;
struct netlbl_audit nai;
smk_netlabel_audit_set(&nai);
if (oldambient != NULL) {
rc = netlbl_cfg_map_del(oldambient, PF_INET, NULL, NULL, &nai);
if (rc != 0)
printk(KERN_WARNING "%s:%d remove rc = %d\n",
__func__, __LINE__, rc);
}
rc = netlbl_cfg_unlbl_map_add(smack_net_ambient, PF_INET,
NULL, NULL, &nai);
if (rc != 0)
printk(KERN_WARNING "%s:%d add rc = %d\n",
__func__, __LINE__, rc);
}
/*
* Seq_file read operations for /smack/cipso
*/
static void *cipso_seq_start(struct seq_file *s, loff_t *pos)
{
if (*pos == SEQ_READ_FINISHED)
return NULL;
if (list_empty(&smack_known_list))
return NULL;
return smack_known_list.next;
}
static void *cipso_seq_next(struct seq_file *s, void *v, loff_t *pos)
{
struct list_head *list = v;
/*
* labels with no associated cipso value wont be printed
* in cipso_seq_show
*/
if (list_is_last(list, &smack_known_list)) {
*pos = SEQ_READ_FINISHED;
return NULL;
}
return list->next;
}
/*
* Print cipso labels in format:
* label level[/cat[,cat]]
*/
static int cipso_seq_show(struct seq_file *s, void *v)
{
struct list_head *list = v;
struct smack_known *skp =
list_entry(list, struct smack_known, list);
struct smack_cipso *scp = skp->smk_cipso;
char *cbp;
char sep = '/';
int cat = 1;
int i;
unsigned char m;
if (scp == NULL)
return 0;
seq_printf(s, "%s %3d", (char *)&skp->smk_known, scp->smk_level);
cbp = scp->smk_catset;
for (i = 0; i < SMK_LABELLEN; i++)
for (m = 0x80; m != 0; m >>= 1) {
if (m & cbp[i]) {
seq_printf(s, "%c%d", sep, cat);
sep = ',';
}
cat++;
}
seq_putc(s, '\n');
return 0;
}
static void cipso_seq_stop(struct seq_file *s, void *v)
{
/* No-op */
}
static const struct seq_operations cipso_seq_ops = {
.start = cipso_seq_start,
.stop = cipso_seq_stop,
.next = cipso_seq_next,
.show = cipso_seq_show,
};
/**
* smk_open_cipso - open() for /smack/cipso
* @inode: inode structure representing file
* @file: "cipso" file pointer
*
* Connect our cipso_seq_* operations with /smack/cipso
* file_operations
*/
static int smk_open_cipso(struct inode *inode, struct file *file)
{
return seq_open(file, &cipso_seq_ops);
}
/**
* smk_write_cipso - write() for /smack/cipso
* @file: file pointer, not actually used
* @buf: where to get the data from
* @count: bytes sent
* @ppos: where to start
*
* Accepts only one cipso rule per write call.
* Returns number of bytes written or error code, as appropriate
*/
static ssize_t smk_write_cipso(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct smack_known *skp;
struct smack_cipso *scp = NULL;
char mapcatset[SMK_LABELLEN];
int maplevel;
int cat;
int catlen;
ssize_t rc = -EINVAL;
char *data = NULL;
char *rule;
int ret;
int i;
/*
* Must have privilege.
* No partial writes.
* Enough data must be present.
*/
if (!capable(CAP_MAC_ADMIN))
return -EPERM;
if (*ppos != 0)
return -EINVAL;
if (count < SMK_CIPSOMIN || count > SMK_CIPSOMAX)
return -EINVAL;
data = kzalloc(count + 1, GFP_KERNEL);
if (data == NULL)
return -ENOMEM;
if (copy_from_user(data, buf, count) != 0) {
rc = -EFAULT;
goto unlockedout;
}
/* labels cannot begin with a '-' */
if (data[0] == '-') {
rc = -EINVAL;
goto unlockedout;
}
data[count] = '\0';
rule = data;
/*
* Only allow one writer at a time. Writes should be
* quite rare and small in any case.
*/
mutex_lock(&smack_cipso_lock);
skp = smk_import_entry(rule, 0);
if (skp == NULL)
goto out;
rule += SMK_LABELLEN;
ret = sscanf(rule, "%d", &maplevel);
if (ret != 1 || maplevel > SMACK_CIPSO_MAXLEVEL)
goto out;
rule += SMK_DIGITLEN;
ret = sscanf(rule, "%d", &catlen);
if (ret != 1 || catlen > SMACK_CIPSO_MAXCATNUM)
goto out;
if (count != (SMK_CIPSOMIN + catlen * SMK_DIGITLEN))
goto out;
memset(mapcatset, 0, sizeof(mapcatset));
for (i = 0; i < catlen; i++) {
rule += SMK_DIGITLEN;
ret = sscanf(rule, "%d", &cat);
if (ret != 1 || cat > SMACK_CIPSO_MAXCATVAL)
goto out;
smack_catset_bit(cat, mapcatset);
}
if (skp->smk_cipso == NULL) {
scp = kzalloc(sizeof(struct smack_cipso), GFP_KERNEL);
if (scp == NULL) {
rc = -ENOMEM;
goto out;
}
}
spin_lock_bh(&skp->smk_cipsolock);
if (scp == NULL)
scp = skp->smk_cipso;
else
skp->smk_cipso = scp;
scp->smk_level = maplevel;
memcpy(scp->smk_catset, mapcatset, sizeof(mapcatset));
spin_unlock_bh(&skp->smk_cipsolock);
rc = count;
out:
mutex_unlock(&smack_cipso_lock);
unlockedout:
kfree(data);
return rc;
}
static const struct file_operations smk_cipso_ops = {
.open = smk_open_cipso,
.read = seq_read,
.llseek = seq_lseek,
.write = smk_write_cipso,
.release = seq_release,
};
/*
* Seq_file read operations for /smack/netlabel
*/
static void *netlbladdr_seq_start(struct seq_file *s, loff_t *pos)
{
if (*pos == SEQ_READ_FINISHED)
return NULL;
if (list_empty(&smk_netlbladdr_list))
return NULL;
return smk_netlbladdr_list.next;
}
static void *netlbladdr_seq_next(struct seq_file *s, void *v, loff_t *pos)
{
struct list_head *list = v;
if (list_is_last(list, &smk_netlbladdr_list)) {
*pos = SEQ_READ_FINISHED;
return NULL;
}
return list->next;
}
#define BEBITS (sizeof(__be32) * 8)
/*
* Print host/label pairs
*/
static int netlbladdr_seq_show(struct seq_file *s, void *v)
{
struct list_head *list = v;
struct smk_netlbladdr *skp =
list_entry(list, struct smk_netlbladdr, list);
unsigned char *hp = (char *) &skp->smk_host.sin_addr.s_addr;
int maskn;
u32 temp_mask = be32_to_cpu(skp->smk_mask.s_addr);
for (maskn = 0; temp_mask; temp_mask <<= 1, maskn++);
seq_printf(s, "%u.%u.%u.%u/%d %s\n",
hp[0], hp[1], hp[2], hp[3], maskn, skp->smk_label);
return 0;
}
static void netlbladdr_seq_stop(struct seq_file *s, void *v)
{
/* No-op */
}
static const struct seq_operations netlbladdr_seq_ops = {
.start = netlbladdr_seq_start,
.stop = netlbladdr_seq_stop,
.next = netlbladdr_seq_next,
.show = netlbladdr_seq_show,
};
/**
* smk_open_netlbladdr - open() for /smack/netlabel
* @inode: inode structure representing file
* @file: "netlabel" file pointer
*
* Connect our netlbladdr_seq_* operations with /smack/netlabel
* file_operations
*/
static int smk_open_netlbladdr(struct inode *inode, struct file *file)
{
return seq_open(file, &netlbladdr_seq_ops);
}
/**
* smk_netlbladdr_insert
* @new : netlabel to insert
*
* This helper insert netlabel in the smack_netlbladdrs list
* sorted by netmask length (longest to smallest)
* locked by &smk_netlbladdr_lock in smk_write_netlbladdr
*
*/
static void smk_netlbladdr_insert(struct smk_netlbladdr *new)
{
struct smk_netlbladdr *m, *m_next;
if (list_empty(&smk_netlbladdr_list)) {
list_add_rcu(&new->list, &smk_netlbladdr_list);
return;
}
m = list_entry_rcu(smk_netlbladdr_list.next,
struct smk_netlbladdr, list);
/* the comparison '>' is a bit hacky, but works */
if (new->smk_mask.s_addr > m->smk_mask.s_addr) {
list_add_rcu(&new->list, &smk_netlbladdr_list);
return;
}
list_for_each_entry_rcu(m, &smk_netlbladdr_list, list) {
if (list_is_last(&m->list, &smk_netlbladdr_list)) {
list_add_rcu(&new->list, &m->list);
return;
}
m_next = list_entry_rcu(m->list.next,
struct smk_netlbladdr, list);
if (new->smk_mask.s_addr > m_next->smk_mask.s_addr) {
list_add_rcu(&new->list, &m->list);
return;
}
}
}
/**
* smk_write_netlbladdr - write() for /smack/netlabel
* @file: file pointer, not actually used
* @buf: where to get the data from
* @count: bytes sent
* @ppos: where to start
*
* Accepts only one netlbladdr per write call.
* Returns number of bytes written or error code, as appropriate
*/
static ssize_t smk_write_netlbladdr(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct smk_netlbladdr *skp;
struct sockaddr_in newname;
char smack[SMK_LABELLEN];
char *sp;
char data[SMK_NETLBLADDRMAX + 1];
char *host = (char *)&newname.sin_addr.s_addr;
int rc;
struct netlbl_audit audit_info;
struct in_addr mask;
unsigned int m;
int found;
u32 mask_bits = (1<<31);
__be32 nsa;
u32 temp_mask;
/*
* Must have privilege.
* No partial writes.
* Enough data must be present.
* "<addr/mask, as a.b.c.d/e><space><label>"
* "<addr, as a.b.c.d><space><label>"
*/
if (!capable(CAP_MAC_ADMIN))
return -EPERM;
if (*ppos != 0)
return -EINVAL;
if (count < SMK_NETLBLADDRMIN || count > SMK_NETLBLADDRMAX)
return -EINVAL;
if (copy_from_user(data, buf, count) != 0)
return -EFAULT;
data[count] = '\0';
rc = sscanf(data, "%hhd.%hhd.%hhd.%hhd/%d %s",
&host[0], &host[1], &host[2], &host[3], &m, smack);
if (rc != 6) {
rc = sscanf(data, "%hhd.%hhd.%hhd.%hhd %s",
&host[0], &host[1], &host[2], &host[3], smack);
if (rc != 5)
return -EINVAL;
m = BEBITS;
}
if (m > BEBITS)
return -EINVAL;
/* if smack begins with '-', its an option, don't import it */
if (smack[0] != '-') {
sp = smk_import(smack, 0);
if (sp == NULL)
return -EINVAL;
} else {
/* check known options */
if (strcmp(smack, smack_cipso_option) == 0)
sp = (char *)smack_cipso_option;
else
return -EINVAL;
}
for (temp_mask = 0; m > 0; m--) {
temp_mask |= mask_bits;
mask_bits >>= 1;
}
mask.s_addr = cpu_to_be32(temp_mask);
newname.sin_addr.s_addr &= mask.s_addr;
/*
* Only allow one writer at a time. Writes should be
* quite rare and small in any case.
*/
mutex_lock(&smk_netlbladdr_lock);
nsa = newname.sin_addr.s_addr;
/* try to find if the prefix is already in the list */
found = 0;
list_for_each_entry_rcu(skp, &smk_netlbladdr_list, list) {
if (skp->smk_host.sin_addr.s_addr == nsa &&
skp->smk_mask.s_addr == mask.s_addr) {
found = 1;
break;
}
}
smk_netlabel_audit_set(&audit_info);
if (found == 0) {
skp = kzalloc(sizeof(*skp), GFP_KERNEL);
if (skp == NULL)
rc = -ENOMEM;
else {
rc = 0;
skp->smk_host.sin_addr.s_addr = newname.sin_addr.s_addr;
skp->smk_mask.s_addr = mask.s_addr;
skp->smk_label = sp;
smk_netlbladdr_insert(skp);
}
} else {
/* we delete the unlabeled entry, only if the previous label
* wasnt the special CIPSO option */
if (skp->smk_label != smack_cipso_option)
rc = netlbl_cfg_unlbl_static_del(&init_net, NULL,
&skp->smk_host.sin_addr, &skp->smk_mask,
PF_INET, &audit_info);
else
rc = 0;
skp->smk_label = sp;
}
/*
* Now tell netlabel about the single label nature of
* this host so that incoming packets get labeled.
* but only if we didn't get the special CIPSO option
*/
if (rc == 0 && sp != smack_cipso_option)
rc = netlbl_cfg_unlbl_static_add(&init_net, NULL,
&skp->smk_host.sin_addr, &skp->smk_mask, PF_INET,
smack_to_secid(skp->smk_label), &audit_info);
if (rc == 0)
rc = count;
mutex_unlock(&smk_netlbladdr_lock);
return rc;
}
static const struct file_operations smk_netlbladdr_ops = {
.open = smk_open_netlbladdr,
.read = seq_read,
.llseek = seq_lseek,
.write = smk_write_netlbladdr,
.release = seq_release,
};
/**
* smk_read_doi - read() for /smack/doi
* @filp: file pointer, not actually used
* @buf: where to put the result
* @count: maximum to send along
* @ppos: where to start
*
* Returns number of bytes read or error code, as appropriate
*/
static ssize_t smk_read_doi(struct file *filp, char __user *buf,
size_t count, loff_t *ppos)
{
char temp[80];
ssize_t rc;
if (*ppos != 0)
return 0;
sprintf(temp, "%d", smk_cipso_doi_value);
rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
return rc;
}
/**
* smk_write_doi - write() for /smack/doi
* @file: file pointer, not actually used
* @buf: where to get the data from
* @count: bytes sent
* @ppos: where to start
*
* Returns number of bytes written or error code, as appropriate
*/
static ssize_t smk_write_doi(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
char temp[80];
int i;
if (!capable(CAP_MAC_ADMIN))
return -EPERM;
if (count >= sizeof(temp) || count == 0)
return -EINVAL;
if (copy_from_user(temp, buf, count) != 0)
return -EFAULT;
temp[count] = '\0';
if (sscanf(temp, "%d", &i) != 1)
return -EINVAL;
smk_cipso_doi_value = i;
smk_cipso_doi();
return count;
}
static const struct file_operations smk_doi_ops = {
.read = smk_read_doi,
.write = smk_write_doi,
};
/**
* smk_read_direct - read() for /smack/direct
* @filp: file pointer, not actually used
* @buf: where to put the result
* @count: maximum to send along
* @ppos: where to start
*
* Returns number of bytes read or error code, as appropriate
*/
static ssize_t smk_read_direct(struct file *filp, char __user *buf,
size_t count, loff_t *ppos)
{
char temp[80];
ssize_t rc;
if (*ppos != 0)
return 0;
sprintf(temp, "%d", smack_cipso_direct);
rc = simple_read_from_buffer(buf, count, ppos, temp, strlen(temp));
return rc;
}
/**
* smk_write_direct - write() for /smack/direct
* @file: file pointer, not actually used
* @buf: where to get the data from
* @count: bytes sent