-
Notifications
You must be signed in to change notification settings - Fork 3
/
auth_gss.c
1644 lines (1461 loc) · 42.2 KB
/
auth_gss.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
/*
* linux/net/sunrpc/auth_gss/auth_gss.c
*
* RPCSEC_GSS client authentication.
*
* Copyright (c) 2000 The Regents of the University of Michigan.
* All rights reserved.
*
* Dug Song <[email protected]>
* Andy Adamson <[email protected]>
*
* 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.
* 3. Neither the name of the University nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED ``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 REGENTS 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.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/pagemap.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/auth.h>
#include <linux/sunrpc/auth_gss.h>
#include <linux/sunrpc/svcauth_gss.h>
#include <linux/sunrpc/gss_err.h>
#include <linux/workqueue.h>
#include <linux/sunrpc/rpc_pipe_fs.h>
#include <linux/sunrpc/gss_api.h>
#include <asm/uaccess.h>
static const struct rpc_authops authgss_ops;
static const struct rpc_credops gss_credops;
static const struct rpc_credops gss_nullops;
#define GSS_RETRY_EXPIRED 5
static unsigned int gss_expired_cred_retry_delay = GSS_RETRY_EXPIRED;
#ifdef RPC_DEBUG
# define RPCDBG_FACILITY RPCDBG_AUTH
#endif
#define GSS_CRED_SLACK (RPC_MAX_AUTH_SIZE * 2)
/* length of a krb5 verifier (48), plus data added before arguments when
* using integrity (two 4-byte integers): */
#define GSS_VERF_SLACK 100
struct gss_auth {
struct kref kref;
struct rpc_auth rpc_auth;
struct gss_api_mech *mech;
enum rpc_gss_svc service;
struct rpc_clnt *client;
/*
* There are two upcall pipes; dentry[1], named "gssd", is used
* for the new text-based upcall; dentry[0] is named after the
* mechanism (for example, "krb5") and exists for
* backwards-compatibility with older gssd's.
*/
struct dentry *dentry[2];
};
/* pipe_version >= 0 if and only if someone has a pipe open. */
static int pipe_version = -1;
static atomic_t pipe_users = ATOMIC_INIT(0);
static DEFINE_SPINLOCK(pipe_version_lock);
static struct rpc_wait_queue pipe_version_rpc_waitqueue;
static DECLARE_WAIT_QUEUE_HEAD(pipe_version_waitqueue);
static void gss_free_ctx(struct gss_cl_ctx *);
static const struct rpc_pipe_ops gss_upcall_ops_v0;
static const struct rpc_pipe_ops gss_upcall_ops_v1;
static inline struct gss_cl_ctx *
gss_get_ctx(struct gss_cl_ctx *ctx)
{
atomic_inc(&ctx->count);
return ctx;
}
static inline void
gss_put_ctx(struct gss_cl_ctx *ctx)
{
if (atomic_dec_and_test(&ctx->count))
gss_free_ctx(ctx);
}
/* gss_cred_set_ctx:
* called by gss_upcall_callback and gss_create_upcall in order
* to set the gss context. The actual exchange of an old context
* and a new one is protected by the inode->i_lock.
*/
static void
gss_cred_set_ctx(struct rpc_cred *cred, struct gss_cl_ctx *ctx)
{
struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base);
if (!test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags))
return;
gss_get_ctx(ctx);
rcu_assign_pointer(gss_cred->gc_ctx, ctx);
set_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
smp_mb__before_clear_bit();
clear_bit(RPCAUTH_CRED_NEW, &cred->cr_flags);
}
static const void *
simple_get_bytes(const void *p, const void *end, void *res, size_t len)
{
const void *q = (const void *)((const char *)p + len);
if (unlikely(q > end || q < p))
return ERR_PTR(-EFAULT);
memcpy(res, p, len);
return q;
}
static inline const void *
simple_get_netobj(const void *p, const void *end, struct xdr_netobj *dest)
{
const void *q;
unsigned int len;
p = simple_get_bytes(p, end, &len, sizeof(len));
if (IS_ERR(p))
return p;
q = (const void *)((const char *)p + len);
if (unlikely(q > end || q < p))
return ERR_PTR(-EFAULT);
dest->data = kmemdup(p, len, GFP_NOFS);
if (unlikely(dest->data == NULL))
return ERR_PTR(-ENOMEM);
dest->len = len;
return q;
}
static struct gss_cl_ctx *
gss_cred_get_ctx(struct rpc_cred *cred)
{
struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base);
struct gss_cl_ctx *ctx = NULL;
rcu_read_lock();
if (gss_cred->gc_ctx)
ctx = gss_get_ctx(gss_cred->gc_ctx);
rcu_read_unlock();
return ctx;
}
static struct gss_cl_ctx *
gss_alloc_context(void)
{
struct gss_cl_ctx *ctx;
ctx = kzalloc(sizeof(*ctx), GFP_NOFS);
if (ctx != NULL) {
ctx->gc_proc = RPC_GSS_PROC_DATA;
ctx->gc_seq = 1; /* NetApp 6.4R1 doesn't accept seq. no. 0 */
spin_lock_init(&ctx->gc_seq_lock);
atomic_set(&ctx->count,1);
}
return ctx;
}
#define GSSD_MIN_TIMEOUT (60 * 60)
static const void *
gss_fill_context(const void *p, const void *end, struct gss_cl_ctx *ctx, struct gss_api_mech *gm)
{
const void *q;
unsigned int seclen;
unsigned int timeout;
u32 window_size;
int ret;
/* First unsigned int gives the lifetime (in seconds) of the cred */
p = simple_get_bytes(p, end, &timeout, sizeof(timeout));
if (IS_ERR(p))
goto err;
if (timeout == 0)
timeout = GSSD_MIN_TIMEOUT;
ctx->gc_expiry = jiffies + (unsigned long)timeout * HZ * 3 / 4;
/* Sequence number window. Determines the maximum number of simultaneous requests */
p = simple_get_bytes(p, end, &window_size, sizeof(window_size));
if (IS_ERR(p))
goto err;
ctx->gc_win = window_size;
/* gssd signals an error by passing ctx->gc_win = 0: */
if (ctx->gc_win == 0) {
/*
* in which case, p points to an error code. Anything other
* than -EKEYEXPIRED gets converted to -EACCES.
*/
p = simple_get_bytes(p, end, &ret, sizeof(ret));
if (!IS_ERR(p))
p = (ret == -EKEYEXPIRED) ? ERR_PTR(-EKEYEXPIRED) :
ERR_PTR(-EACCES);
goto err;
}
/* copy the opaque wire context */
p = simple_get_netobj(p, end, &ctx->gc_wire_ctx);
if (IS_ERR(p))
goto err;
/* import the opaque security context */
p = simple_get_bytes(p, end, &seclen, sizeof(seclen));
if (IS_ERR(p))
goto err;
q = (const void *)((const char *)p + seclen);
if (unlikely(q > end || q < p)) {
p = ERR_PTR(-EFAULT);
goto err;
}
ret = gss_import_sec_context(p, seclen, gm, &ctx->gc_gss_ctx, GFP_NOFS);
if (ret < 0) {
p = ERR_PTR(ret);
goto err;
}
return q;
err:
dprintk("RPC: gss_fill_context returning %ld\n", -PTR_ERR(p));
return p;
}
#define UPCALL_BUF_LEN 128
struct gss_upcall_msg {
atomic_t count;
uid_t uid;
struct rpc_pipe_msg msg;
struct list_head list;
struct gss_auth *auth;
struct rpc_inode *inode;
struct rpc_wait_queue rpc_waitqueue;
wait_queue_head_t waitqueue;
struct gss_cl_ctx *ctx;
char databuf[UPCALL_BUF_LEN];
};
static int get_pipe_version(void)
{
int ret;
spin_lock(&pipe_version_lock);
if (pipe_version >= 0) {
atomic_inc(&pipe_users);
ret = pipe_version;
} else
ret = -EAGAIN;
spin_unlock(&pipe_version_lock);
return ret;
}
static void put_pipe_version(void)
{
if (atomic_dec_and_lock(&pipe_users, &pipe_version_lock)) {
pipe_version = -1;
spin_unlock(&pipe_version_lock);
}
}
static void
gss_release_msg(struct gss_upcall_msg *gss_msg)
{
if (!atomic_dec_and_test(&gss_msg->count))
return;
put_pipe_version();
BUG_ON(!list_empty(&gss_msg->list));
if (gss_msg->ctx != NULL)
gss_put_ctx(gss_msg->ctx);
rpc_destroy_wait_queue(&gss_msg->rpc_waitqueue);
kfree(gss_msg);
}
static struct gss_upcall_msg *
__gss_find_upcall(struct rpc_inode *rpci, uid_t uid)
{
struct gss_upcall_msg *pos;
list_for_each_entry(pos, &rpci->in_downcall, list) {
if (pos->uid != uid)
continue;
atomic_inc(&pos->count);
dprintk("RPC: gss_find_upcall found msg %p\n", pos);
return pos;
}
dprintk("RPC: gss_find_upcall found nothing\n");
return NULL;
}
/* Try to add an upcall to the pipefs queue.
* If an upcall owned by our uid already exists, then we return a reference
* to that upcall instead of adding the new upcall.
*/
static inline struct gss_upcall_msg *
gss_add_msg(struct gss_upcall_msg *gss_msg)
{
struct rpc_inode *rpci = gss_msg->inode;
struct inode *inode = &rpci->vfs_inode;
struct gss_upcall_msg *old;
spin_lock(&inode->i_lock);
old = __gss_find_upcall(rpci, gss_msg->uid);
if (old == NULL) {
atomic_inc(&gss_msg->count);
list_add(&gss_msg->list, &rpci->in_downcall);
} else
gss_msg = old;
spin_unlock(&inode->i_lock);
return gss_msg;
}
static void
__gss_unhash_msg(struct gss_upcall_msg *gss_msg)
{
list_del_init(&gss_msg->list);
rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno);
wake_up_all(&gss_msg->waitqueue);
atomic_dec(&gss_msg->count);
}
static void
gss_unhash_msg(struct gss_upcall_msg *gss_msg)
{
struct inode *inode = &gss_msg->inode->vfs_inode;
if (list_empty(&gss_msg->list))
return;
spin_lock(&inode->i_lock);
if (!list_empty(&gss_msg->list))
__gss_unhash_msg(gss_msg);
spin_unlock(&inode->i_lock);
}
static void
gss_handle_downcall_result(struct gss_cred *gss_cred, struct gss_upcall_msg *gss_msg)
{
switch (gss_msg->msg.errno) {
case 0:
if (gss_msg->ctx == NULL)
break;
clear_bit(RPCAUTH_CRED_NEGATIVE, &gss_cred->gc_base.cr_flags);
gss_cred_set_ctx(&gss_cred->gc_base, gss_msg->ctx);
break;
case -EKEYEXPIRED:
set_bit(RPCAUTH_CRED_NEGATIVE, &gss_cred->gc_base.cr_flags);
}
gss_cred->gc_upcall_timestamp = jiffies;
gss_cred->gc_upcall = NULL;
rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno);
}
static void
gss_upcall_callback(struct rpc_task *task)
{
struct gss_cred *gss_cred = container_of(task->tk_rqstp->rq_cred,
struct gss_cred, gc_base);
struct gss_upcall_msg *gss_msg = gss_cred->gc_upcall;
struct inode *inode = &gss_msg->inode->vfs_inode;
spin_lock(&inode->i_lock);
gss_handle_downcall_result(gss_cred, gss_msg);
spin_unlock(&inode->i_lock);
task->tk_status = gss_msg->msg.errno;
gss_release_msg(gss_msg);
}
static void gss_encode_v0_msg(struct gss_upcall_msg *gss_msg)
{
gss_msg->msg.data = &gss_msg->uid;
gss_msg->msg.len = sizeof(gss_msg->uid);
}
static void gss_encode_v1_msg(struct gss_upcall_msg *gss_msg,
struct rpc_clnt *clnt, int machine_cred)
{
struct gss_api_mech *mech = gss_msg->auth->mech;
char *p = gss_msg->databuf;
int len = 0;
gss_msg->msg.len = sprintf(gss_msg->databuf, "mech=%s uid=%d ",
mech->gm_name,
gss_msg->uid);
p += gss_msg->msg.len;
if (clnt->cl_principal) {
len = sprintf(p, "target=%s ", clnt->cl_principal);
p += len;
gss_msg->msg.len += len;
}
if (machine_cred) {
len = sprintf(p, "service=* ");
p += len;
gss_msg->msg.len += len;
} else if (!strcmp(clnt->cl_program->name, "nfs4_cb")) {
len = sprintf(p, "service=nfs ");
p += len;
gss_msg->msg.len += len;
}
if (mech->gm_upcall_enctypes) {
len = sprintf(p, mech->gm_upcall_enctypes);
p += len;
gss_msg->msg.len += len;
}
len = sprintf(p, "\n");
gss_msg->msg.len += len;
gss_msg->msg.data = gss_msg->databuf;
BUG_ON(gss_msg->msg.len > UPCALL_BUF_LEN);
}
static void gss_encode_msg(struct gss_upcall_msg *gss_msg,
struct rpc_clnt *clnt, int machine_cred)
{
if (pipe_version == 0)
gss_encode_v0_msg(gss_msg);
else /* pipe_version == 1 */
gss_encode_v1_msg(gss_msg, clnt, machine_cred);
}
static inline struct gss_upcall_msg *
gss_alloc_msg(struct gss_auth *gss_auth, uid_t uid, struct rpc_clnt *clnt,
int machine_cred)
{
struct gss_upcall_msg *gss_msg;
int vers;
gss_msg = kzalloc(sizeof(*gss_msg), GFP_NOFS);
if (gss_msg == NULL)
return ERR_PTR(-ENOMEM);
vers = get_pipe_version();
if (vers < 0) {
kfree(gss_msg);
return ERR_PTR(vers);
}
gss_msg->inode = RPC_I(gss_auth->dentry[vers]->d_inode);
INIT_LIST_HEAD(&gss_msg->list);
rpc_init_wait_queue(&gss_msg->rpc_waitqueue, "RPCSEC_GSS upcall waitq");
init_waitqueue_head(&gss_msg->waitqueue);
atomic_set(&gss_msg->count, 1);
gss_msg->uid = uid;
gss_msg->auth = gss_auth;
gss_encode_msg(gss_msg, clnt, machine_cred);
return gss_msg;
}
static struct gss_upcall_msg *
gss_setup_upcall(struct rpc_clnt *clnt, struct gss_auth *gss_auth, struct rpc_cred *cred)
{
struct gss_cred *gss_cred = container_of(cred,
struct gss_cred, gc_base);
struct gss_upcall_msg *gss_new, *gss_msg;
uid_t uid = cred->cr_uid;
gss_new = gss_alloc_msg(gss_auth, uid, clnt, gss_cred->gc_machine_cred);
if (IS_ERR(gss_new))
return gss_new;
gss_msg = gss_add_msg(gss_new);
if (gss_msg == gss_new) {
struct inode *inode = &gss_new->inode->vfs_inode;
int res = rpc_queue_upcall(inode, &gss_new->msg);
if (res) {
gss_unhash_msg(gss_new);
gss_msg = ERR_PTR(res);
}
} else
gss_release_msg(gss_new);
return gss_msg;
}
static void warn_gssd(void)
{
static unsigned long ratelimit;
unsigned long now = jiffies;
if (time_after(now, ratelimit)) {
printk(KERN_WARNING "RPC: AUTH_GSS upcall timed out.\n"
"Please check user daemon is running.\n");
ratelimit = now + 15*HZ;
}
}
static inline int
gss_refresh_upcall(struct rpc_task *task)
{
struct rpc_cred *cred = task->tk_rqstp->rq_cred;
struct gss_auth *gss_auth = container_of(cred->cr_auth,
struct gss_auth, rpc_auth);
struct gss_cred *gss_cred = container_of(cred,
struct gss_cred, gc_base);
struct gss_upcall_msg *gss_msg;
struct inode *inode;
int err = 0;
dprintk("RPC: %5u gss_refresh_upcall for uid %u\n", task->tk_pid,
cred->cr_uid);
gss_msg = gss_setup_upcall(task->tk_client, gss_auth, cred);
if (PTR_ERR(gss_msg) == -EAGAIN) {
/* XXX: warning on the first, under the assumption we
* shouldn't normally hit this case on a refresh. */
warn_gssd();
task->tk_timeout = 15*HZ;
rpc_sleep_on(&pipe_version_rpc_waitqueue, task, NULL);
return 0;
}
if (IS_ERR(gss_msg)) {
err = PTR_ERR(gss_msg);
goto out;
}
inode = &gss_msg->inode->vfs_inode;
spin_lock(&inode->i_lock);
if (gss_cred->gc_upcall != NULL)
rpc_sleep_on(&gss_cred->gc_upcall->rpc_waitqueue, task, NULL);
else if (gss_msg->ctx == NULL && gss_msg->msg.errno >= 0) {
task->tk_timeout = 0;
gss_cred->gc_upcall = gss_msg;
/* gss_upcall_callback will release the reference to gss_upcall_msg */
atomic_inc(&gss_msg->count);
rpc_sleep_on(&gss_msg->rpc_waitqueue, task, gss_upcall_callback);
} else {
gss_handle_downcall_result(gss_cred, gss_msg);
err = gss_msg->msg.errno;
}
spin_unlock(&inode->i_lock);
gss_release_msg(gss_msg);
out:
dprintk("RPC: %5u gss_refresh_upcall for uid %u result %d\n",
task->tk_pid, cred->cr_uid, err);
return err;
}
static inline int
gss_create_upcall(struct gss_auth *gss_auth, struct gss_cred *gss_cred)
{
struct inode *inode;
struct rpc_cred *cred = &gss_cred->gc_base;
struct gss_upcall_msg *gss_msg;
DEFINE_WAIT(wait);
int err = 0;
dprintk("RPC: gss_upcall for uid %u\n", cred->cr_uid);
retry:
gss_msg = gss_setup_upcall(gss_auth->client, gss_auth, cred);
if (PTR_ERR(gss_msg) == -EAGAIN) {
err = wait_event_interruptible_timeout(pipe_version_waitqueue,
pipe_version >= 0, 15*HZ);
if (err)
goto out;
if (pipe_version < 0)
warn_gssd();
goto retry;
}
if (IS_ERR(gss_msg)) {
err = PTR_ERR(gss_msg);
goto out;
}
inode = &gss_msg->inode->vfs_inode;
for (;;) {
prepare_to_wait(&gss_msg->waitqueue, &wait, TASK_INTERRUPTIBLE);
spin_lock(&inode->i_lock);
if (gss_msg->ctx != NULL || gss_msg->msg.errno < 0) {
break;
}
spin_unlock(&inode->i_lock);
if (signalled()) {
err = -ERESTARTSYS;
goto out_intr;
}
schedule();
}
if (gss_msg->ctx)
gss_cred_set_ctx(cred, gss_msg->ctx);
else
err = gss_msg->msg.errno;
spin_unlock(&inode->i_lock);
out_intr:
finish_wait(&gss_msg->waitqueue, &wait);
gss_release_msg(gss_msg);
out:
dprintk("RPC: gss_create_upcall for uid %u result %d\n",
cred->cr_uid, err);
return err;
}
static ssize_t
gss_pipe_upcall(struct file *filp, struct rpc_pipe_msg *msg,
char __user *dst, size_t buflen)
{
char *data = (char *)msg->data + msg->copied;
size_t mlen = min(msg->len, buflen);
unsigned long left;
left = copy_to_user(dst, data, mlen);
if (left == mlen) {
msg->errno = -EFAULT;
return -EFAULT;
}
mlen -= left;
msg->copied += mlen;
msg->errno = 0;
return mlen;
}
#define MSG_BUF_MAXSIZE 1024
static ssize_t
gss_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
{
const void *p, *end;
void *buf;
struct gss_upcall_msg *gss_msg;
struct inode *inode = filp->f_path.dentry->d_inode;
struct gss_cl_ctx *ctx;
uid_t uid;
ssize_t err = -EFBIG;
if (mlen > MSG_BUF_MAXSIZE)
goto out;
err = -ENOMEM;
buf = kmalloc(mlen, GFP_NOFS);
if (!buf)
goto out;
err = -EFAULT;
if (copy_from_user(buf, src, mlen))
goto err;
end = (const void *)((char *)buf + mlen);
p = simple_get_bytes(buf, end, &uid, sizeof(uid));
if (IS_ERR(p)) {
err = PTR_ERR(p);
goto err;
}
err = -ENOMEM;
ctx = gss_alloc_context();
if (ctx == NULL)
goto err;
err = -ENOENT;
/* Find a matching upcall */
spin_lock(&inode->i_lock);
gss_msg = __gss_find_upcall(RPC_I(inode), uid);
if (gss_msg == NULL) {
spin_unlock(&inode->i_lock);
goto err_put_ctx;
}
list_del_init(&gss_msg->list);
spin_unlock(&inode->i_lock);
p = gss_fill_context(p, end, ctx, gss_msg->auth->mech);
if (IS_ERR(p)) {
err = PTR_ERR(p);
switch (err) {
case -EACCES:
case -EKEYEXPIRED:
gss_msg->msg.errno = err;
err = mlen;
break;
case -EFAULT:
case -ENOMEM:
case -EINVAL:
case -ENOSYS:
gss_msg->msg.errno = -EAGAIN;
break;
default:
printk(KERN_CRIT "%s: bad return from "
"gss_fill_context: %zd\n", __func__, err);
BUG();
}
goto err_release_msg;
}
gss_msg->ctx = gss_get_ctx(ctx);
err = mlen;
err_release_msg:
spin_lock(&inode->i_lock);
__gss_unhash_msg(gss_msg);
spin_unlock(&inode->i_lock);
gss_release_msg(gss_msg);
err_put_ctx:
gss_put_ctx(ctx);
err:
kfree(buf);
out:
dprintk("RPC: gss_pipe_downcall returning %Zd\n", err);
return err;
}
static int gss_pipe_open(struct inode *inode, int new_version)
{
int ret = 0;
spin_lock(&pipe_version_lock);
if (pipe_version < 0) {
/* First open of any gss pipe determines the version: */
pipe_version = new_version;
rpc_wake_up(&pipe_version_rpc_waitqueue);
wake_up(&pipe_version_waitqueue);
} else if (pipe_version != new_version) {
/* Trying to open a pipe of a different version */
ret = -EBUSY;
goto out;
}
atomic_inc(&pipe_users);
out:
spin_unlock(&pipe_version_lock);
return ret;
}
static int gss_pipe_open_v0(struct inode *inode)
{
return gss_pipe_open(inode, 0);
}
static int gss_pipe_open_v1(struct inode *inode)
{
return gss_pipe_open(inode, 1);
}
static void
gss_pipe_release(struct inode *inode)
{
struct rpc_inode *rpci = RPC_I(inode);
struct gss_upcall_msg *gss_msg;
restart:
spin_lock(&inode->i_lock);
list_for_each_entry(gss_msg, &rpci->in_downcall, list) {
if (!list_empty(&gss_msg->msg.list))
continue;
gss_msg->msg.errno = -EPIPE;
atomic_inc(&gss_msg->count);
__gss_unhash_msg(gss_msg);
spin_unlock(&inode->i_lock);
gss_release_msg(gss_msg);
goto restart;
}
spin_unlock(&inode->i_lock);
put_pipe_version();
}
static void
gss_pipe_destroy_msg(struct rpc_pipe_msg *msg)
{
struct gss_upcall_msg *gss_msg = container_of(msg, struct gss_upcall_msg, msg);
if (msg->errno < 0) {
dprintk("RPC: gss_pipe_destroy_msg releasing msg %p\n",
gss_msg);
atomic_inc(&gss_msg->count);
gss_unhash_msg(gss_msg);
if (msg->errno == -ETIMEDOUT)
warn_gssd();
gss_release_msg(gss_msg);
}
}
/*
* NOTE: we have the opportunity to use different
* parameters based on the input flavor (which must be a pseudoflavor)
*/
static struct rpc_auth *
gss_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
{
struct gss_auth *gss_auth;
struct rpc_auth * auth;
int err = -ENOMEM; /* XXX? */
dprintk("RPC: creating GSS authenticator for client %p\n", clnt);
if (!try_module_get(THIS_MODULE))
return ERR_PTR(err);
if (!(gss_auth = kmalloc(sizeof(*gss_auth), GFP_KERNEL)))
goto out_dec;
gss_auth->client = clnt;
err = -EINVAL;
gss_auth->mech = gss_mech_get_by_pseudoflavor(flavor);
if (!gss_auth->mech) {
printk(KERN_WARNING "%s: Pseudoflavor %d not found!\n",
__func__, flavor);
goto err_free;
}
gss_auth->service = gss_pseudoflavor_to_service(gss_auth->mech, flavor);
if (gss_auth->service == 0)
goto err_put_mech;
auth = &gss_auth->rpc_auth;
auth->au_cslack = GSS_CRED_SLACK >> 2;
auth->au_rslack = GSS_VERF_SLACK >> 2;
auth->au_ops = &authgss_ops;
auth->au_flavor = flavor;
atomic_set(&auth->au_count, 1);
kref_init(&gss_auth->kref);
/*
* Note: if we created the old pipe first, then someone who
* examined the directory at the right moment might conclude
* that we supported only the old pipe. So we instead create
* the new pipe first.
*/
gss_auth->dentry[1] = rpc_mkpipe(clnt->cl_path.dentry,
"gssd",
clnt, &gss_upcall_ops_v1,
RPC_PIPE_WAIT_FOR_OPEN);
if (IS_ERR(gss_auth->dentry[1])) {
err = PTR_ERR(gss_auth->dentry[1]);
goto err_put_mech;
}
gss_auth->dentry[0] = rpc_mkpipe(clnt->cl_path.dentry,
gss_auth->mech->gm_name,
clnt, &gss_upcall_ops_v0,
RPC_PIPE_WAIT_FOR_OPEN);
if (IS_ERR(gss_auth->dentry[0])) {
err = PTR_ERR(gss_auth->dentry[0]);
goto err_unlink_pipe_1;
}
err = rpcauth_init_credcache(auth);
if (err)
goto err_unlink_pipe_0;
return auth;
err_unlink_pipe_0:
rpc_unlink(gss_auth->dentry[0]);
err_unlink_pipe_1:
rpc_unlink(gss_auth->dentry[1]);
err_put_mech:
gss_mech_put(gss_auth->mech);
err_free:
kfree(gss_auth);
out_dec:
module_put(THIS_MODULE);
return ERR_PTR(err);
}
static void
gss_free(struct gss_auth *gss_auth)
{
rpc_unlink(gss_auth->dentry[1]);
rpc_unlink(gss_auth->dentry[0]);
gss_mech_put(gss_auth->mech);
kfree(gss_auth);
module_put(THIS_MODULE);
}
static void
gss_free_callback(struct kref *kref)
{
struct gss_auth *gss_auth = container_of(kref, struct gss_auth, kref);
gss_free(gss_auth);
}
static void
gss_destroy(struct rpc_auth *auth)
{
struct gss_auth *gss_auth;
dprintk("RPC: destroying GSS authenticator %p flavor %d\n",
auth, auth->au_flavor);
rpcauth_destroy_credcache(auth);
gss_auth = container_of(auth, struct gss_auth, rpc_auth);
kref_put(&gss_auth->kref, gss_free_callback);
}
/*
* gss_destroying_context will cause the RPCSEC_GSS to send a NULL RPC call
* to the server with the GSS control procedure field set to
* RPC_GSS_PROC_DESTROY. This should normally cause the server to release
* all RPCSEC_GSS state associated with that context.
*/
static int
gss_destroying_context(struct rpc_cred *cred)
{
struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base);
struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth);
struct rpc_task *task;
if (gss_cred->gc_ctx == NULL ||
test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) == 0)
return 0;
gss_cred->gc_ctx->gc_proc = RPC_GSS_PROC_DESTROY;
cred->cr_ops = &gss_nullops;
/* Take a reference to ensure the cred will be destroyed either
* by the RPC call or by the put_rpccred() below */
get_rpccred(cred);
task = rpc_call_null(gss_auth->client, cred, RPC_TASK_ASYNC|RPC_TASK_SOFT);
if (!IS_ERR(task))
rpc_put_task(task);
put_rpccred(cred);
return 1;
}
/* gss_destroy_cred (and gss_free_ctx) are used to clean up after failure
* to create a new cred or context, so they check that things have been
* allocated before freeing them. */
static void
gss_do_free_ctx(struct gss_cl_ctx *ctx)
{
dprintk("RPC: gss_free_ctx\n");
gss_delete_sec_context(&ctx->gc_gss_ctx);
kfree(ctx->gc_wire_ctx.data);
kfree(ctx);
}
static void
gss_free_ctx_callback(struct rcu_head *head)
{
struct gss_cl_ctx *ctx = container_of(head, struct gss_cl_ctx, gc_rcu);
gss_do_free_ctx(ctx);
}
static void
gss_free_ctx(struct gss_cl_ctx *ctx)
{
call_rcu(&ctx->gc_rcu, gss_free_ctx_callback);
}
static void
gss_free_cred(struct gss_cred *gss_cred)
{
dprintk("RPC: gss_free_cred %p\n", gss_cred);
kfree(gss_cred);
}
static void
gss_free_cred_callback(struct rcu_head *head)
{
struct gss_cred *gss_cred = container_of(head, struct gss_cred, gc_base.cr_rcu);
gss_free_cred(gss_cred);
}
static void
gss_destroy_nullcred(struct rpc_cred *cred)
{
struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base);
struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth);
struct gss_cl_ctx *ctx = gss_cred->gc_ctx;
rcu_assign_pointer(gss_cred->gc_ctx, NULL);
call_rcu(&cred->cr_rcu, gss_free_cred_callback);
if (ctx)
gss_put_ctx(ctx);
kref_put(&gss_auth->kref, gss_free_callback);
}
static void
gss_destroy_cred(struct rpc_cred *cred)
{
if (gss_destroying_context(cred))
return;
gss_destroy_nullcred(cred);
}
/*
* Lookup RPCSEC_GSS cred for the current process
*/
static struct rpc_cred *
gss_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
{
return rpcauth_lookup_credcache(auth, acred, flags);
}
static struct rpc_cred *
gss_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
{
struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth);
struct gss_cred *cred = NULL;