forked from aosp-mirror/platform_external_strace
-
Notifications
You must be signed in to change notification settings - Fork 0
/
Copy pathsyscall.c
2839 lines (2664 loc) · 66.9 KB
/
syscall.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) 1991, 1992 Paul Kranenburg <pk@cs.few.eur.nl>
* Copyright (c) 1993 Branko Lankester <branko@hacktic.nl>
* Copyright (c) 1993, 1994, 1995, 1996 Rick Sladkey <jrs@world.std.com>
* Copyright (c) 1996-1999 Wichert Akkerman <wichert@cistron.nl>
* Copyright (c) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
* Linux for s390 port by D.J. Barrow
* <barrow_dj@mail.yahoo.com,djbarrow@de.ibm.com>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR 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.
*
* $Id$
*/
#include "defs.h"
#include <signal.h>
#include <time.h>
#include <errno.h>
#ifndef HAVE_ANDROID_OS
#include <sys/user.h>
#endif
#include <sys/syscall.h>
#include <sys/param.h>
#ifdef HAVE_SYS_REG_H
#include <sys/reg.h>
#ifndef PTRACE_PEEKUSR
# define PTRACE_PEEKUSR PTRACE_PEEKUSER
#endif
#elif defined(HAVE_LINUX_PTRACE_H)
#undef PTRACE_SYSCALL
# ifdef HAVE_STRUCT_IA64_FPREG
# define ia64_fpreg XXX_ia64_fpreg
# endif
# ifdef HAVE_STRUCT_PT_ALL_USER_REGS
# define pt_all_user_regs XXX_pt_all_user_regs
# endif
#include <linux/ptrace.h>
# undef ia64_fpreg
# undef pt_all_user_regs
#endif
#if defined (LINUX) && defined (SPARC64)
# undef PTRACE_GETREGS
# define PTRACE_GETREGS PTRACE_GETREGS64
# undef PTRACE_SETREGS
# define PTRACE_SETREGS PTRACE_SETREGS64
#endif /* LINUX && SPARC64 */
#if defined(LINUX) && defined(IA64)
# include <asm/ptrace_offsets.h>
# include <asm/rse.h>
#endif
#define NR_SYSCALL_BASE 0
#ifdef LINUX
#ifndef ERESTARTSYS
#define ERESTARTSYS 512
#endif
#ifndef ERESTARTNOINTR
#define ERESTARTNOINTR 513
#endif
#ifndef ERESTARTNOHAND
#define ERESTARTNOHAND 514 /* restart if no handler.. */
#endif
#ifndef ENOIOCTLCMD
#define ENOIOCTLCMD 515 /* No ioctl command */
#endif
#ifndef ERESTART_RESTARTBLOCK
#define ERESTART_RESTARTBLOCK 516 /* restart by calling sys_restart_syscall */
#endif
#ifndef NSIG
#define NSIG 32
#endif
#ifdef ARM
#undef NSIG
#define NSIG 32
#undef NR_SYSCALL_BASE
#define NR_SYSCALL_BASE __NR_SYSCALL_BASE
#endif
#endif /* LINUX */
#include "syscall.h"
/* Define these shorthand notations to simplify the syscallent files. */
#define TD TRACE_DESC
#define TF TRACE_FILE
#define TI TRACE_IPC
#define TN TRACE_NETWORK
#define TP TRACE_PROCESS
#define TS TRACE_SIGNAL
#define NF SYSCALL_NEVER_FAILS
static const struct sysent sysent0[] = {
#include "syscallent.h"
};
static const int nsyscalls0 = sizeof sysent0 / sizeof sysent0[0];
int qual_flags0[MAX_QUALS];
#if SUPPORTED_PERSONALITIES >= 2
static const struct sysent sysent1[] = {
#include "syscallent1.h"
};
static const int nsyscalls1 = sizeof sysent1 / sizeof sysent1[0];
int qual_flags1[MAX_QUALS];
#endif /* SUPPORTED_PERSONALITIES >= 2 */
#if SUPPORTED_PERSONALITIES >= 3
static const struct sysent sysent2[] = {
#include "syscallent2.h"
};
static const int nsyscalls2 = sizeof sysent2 / sizeof sysent2[0];
int qual_flags2[MAX_QUALS];
#endif /* SUPPORTED_PERSONALITIES >= 3 */
const struct sysent *sysent;
int *qual_flags;
int nsyscalls;
/* Now undef them since short defines cause wicked namespace pollution. */
#undef TD
#undef TF
#undef TI
#undef TN
#undef TP
#undef TS
#undef NF
static const char *const errnoent0[] = {
#include "errnoent.h"
};
static const int nerrnos0 = sizeof errnoent0 / sizeof errnoent0[0];
#if SUPPORTED_PERSONALITIES >= 2
static const char *const errnoent1[] = {
#include "errnoent1.h"
};
static const int nerrnos1 = sizeof errnoent1 / sizeof errnoent1[0];
#endif /* SUPPORTED_PERSONALITIES >= 2 */
#if SUPPORTED_PERSONALITIES >= 3
static const char *const errnoent2[] = {
#include "errnoent2.h"
};
static const int nerrnos2 = sizeof errnoent2 / sizeof errnoent2[0];
#endif /* SUPPORTED_PERSONALITIES >= 3 */
const char *const *errnoent;
int nerrnos;
int current_personality;
#ifndef PERSONALITY0_WORDSIZE
# define PERSONALITY0_WORDSIZE sizeof(long)
#endif
const int personality_wordsize[SUPPORTED_PERSONALITIES] = {
PERSONALITY0_WORDSIZE,
#if SUPPORTED_PERSONALITIES > 1
PERSONALITY1_WORDSIZE,
#endif
#if SUPPORTED_PERSONALITIES > 2
PERSONALITY2_WORDSIZE,
#endif
};;
int
set_personality(int personality)
{
switch (personality) {
case 0:
errnoent = errnoent0;
nerrnos = nerrnos0;
sysent = sysent0;
nsyscalls = nsyscalls0;
ioctlent = ioctlent0;
nioctlents = nioctlents0;
signalent = signalent0;
nsignals = nsignals0;
qual_flags = qual_flags0;
break;
#if SUPPORTED_PERSONALITIES >= 2
case 1:
errnoent = errnoent1;
nerrnos = nerrnos1;
sysent = sysent1;
nsyscalls = nsyscalls1;
ioctlent = ioctlent1;
nioctlents = nioctlents1;
signalent = signalent1;
nsignals = nsignals1;
qual_flags = qual_flags1;
break;
#endif /* SUPPORTED_PERSONALITIES >= 2 */
#if SUPPORTED_PERSONALITIES >= 3
case 2:
errnoent = errnoent2;
nerrnos = nerrnos2;
sysent = sysent2;
nsyscalls = nsyscalls2;
ioctlent = ioctlent2;
nioctlents = nioctlents2;
signalent = signalent2;
nsignals = nsignals2;
qual_flags = qual_flags2;
break;
#endif /* SUPPORTED_PERSONALITIES >= 3 */
default:
return -1;
}
current_personality = personality;
return 0;
}
static int qual_syscall(), qual_signal(), qual_fault(), qual_desc();
static const struct qual_options {
int bitflag;
const char *option_name;
int (*qualify)(const char *, int, int);
const char *argument_name;
} qual_options[] = {
{ QUAL_TRACE, "trace", qual_syscall, "system call" },
{ QUAL_TRACE, "t", qual_syscall, "system call" },
{ QUAL_ABBREV, "abbrev", qual_syscall, "system call" },
{ QUAL_ABBREV, "a", qual_syscall, "system call" },
{ QUAL_VERBOSE, "verbose", qual_syscall, "system call" },
{ QUAL_VERBOSE, "v", qual_syscall, "system call" },
{ QUAL_RAW, "raw", qual_syscall, "system call" },
{ QUAL_RAW, "x", qual_syscall, "system call" },
{ QUAL_SIGNAL, "signal", qual_signal, "signal" },
{ QUAL_SIGNAL, "signals", qual_signal, "signal" },
{ QUAL_SIGNAL, "s", qual_signal, "signal" },
{ QUAL_FAULT, "fault", qual_fault, "fault" },
{ QUAL_FAULT, "faults", qual_fault, "fault" },
{ QUAL_FAULT, "m", qual_fault, "fault" },
{ QUAL_READ, "read", qual_desc, "descriptor" },
{ QUAL_READ, "reads", qual_desc, "descriptor" },
{ QUAL_READ, "r", qual_desc, "descriptor" },
{ QUAL_WRITE, "write", qual_desc, "descriptor" },
{ QUAL_WRITE, "writes", qual_desc, "descriptor" },
{ QUAL_WRITE, "w", qual_desc, "descriptor" },
{ 0, NULL, NULL, NULL },
};
static void
qualify_one(int n, int bitflag, int not, int pers)
{
if (pers == 0 || pers < 0) {
if (not)
qual_flags0[n] &= ~bitflag;
else
qual_flags0[n] |= bitflag;
}
#if SUPPORTED_PERSONALITIES >= 2
if (pers == 1 || pers < 0) {
if (not)
qual_flags1[n] &= ~bitflag;
else
qual_flags1[n] |= bitflag;
}
#endif /* SUPPORTED_PERSONALITIES >= 2 */
#if SUPPORTED_PERSONALITIES >= 3
if (pers == 2 || pers < 0) {
if (not)
qual_flags2[n] &= ~bitflag;
else
qual_flags2[n] |= bitflag;
}
#endif /* SUPPORTED_PERSONALITIES >= 3 */
}
static int
qual_syscall(const char *s, int bitflag, int not)
{
int i;
int rc = -1;
if (isdigit((unsigned char)*s)) {
int i = atoi(s);
if (i < 0 || i >= MAX_QUALS)
return -1;
qualify_one(i, bitflag, not, -1);
return 0;
}
for (i = 0; i < nsyscalls0; i++)
if (strcmp(s, sysent0[i].sys_name) == 0) {
qualify_one(i, bitflag, not, 0);
rc = 0;
}
#if SUPPORTED_PERSONALITIES >= 2
for (i = 0; i < nsyscalls1; i++)
if (strcmp(s, sysent1[i].sys_name) == 0) {
qualify_one(i, bitflag, not, 1);
rc = 0;
}
#endif /* SUPPORTED_PERSONALITIES >= 2 */
#if SUPPORTED_PERSONALITIES >= 3
for (i = 0; i < nsyscalls2; i++)
if (strcmp(s, sysent2[i].sys_name) == 0) {
qualify_one(i, bitflag, not, 2);
rc = 0;
}
#endif /* SUPPORTED_PERSONALITIES >= 3 */
return rc;
}
static int
qual_signal(const char *s, int bitflag, int not)
{
int i;
char buf[32];
if (isdigit((unsigned char)*s)) {
int signo = atoi(s);
if (signo < 0 || signo >= MAX_QUALS)
return -1;
qualify_one(signo, bitflag, not, -1);
return 0;
}
if (strlen(s) >= sizeof buf)
return -1;
strcpy(buf, s);
s = buf;
if (strncasecmp(s, "SIG", 3) == 0)
s += 3;
for (i = 0; i <= NSIG; i++)
if (strcasecmp(s, signame(i) + 3) == 0) {
qualify_one(i, bitflag, not, -1);
return 0;
}
return -1;
}
static int
qual_fault(const char *s, int bitflag, int not)
{
return -1;
}
static int
qual_desc(const char *s, int bitflag, int not)
{
if (isdigit((unsigned char)*s)) {
int desc = atoi(s);
if (desc < 0 || desc >= MAX_QUALS)
return -1;
qualify_one(desc, bitflag, not, -1);
return 0;
}
return -1;
}
static int
lookup_class(const char *s)
{
if (strcmp(s, "file") == 0)
return TRACE_FILE;
if (strcmp(s, "ipc") == 0)
return TRACE_IPC;
if (strcmp(s, "network") == 0)
return TRACE_NETWORK;
if (strcmp(s, "process") == 0)
return TRACE_PROCESS;
if (strcmp(s, "signal") == 0)
return TRACE_SIGNAL;
if (strcmp(s, "desc") == 0)
return TRACE_DESC;
return -1;
}
void
qualify(const char *s)
{
const struct qual_options *opt;
int not;
char *copy;
const char *p;
int i, n;
opt = &qual_options[0];
for (i = 0; (p = qual_options[i].option_name); i++) {
n = strlen(p);
if (strncmp(s, p, n) == 0 && s[n] == '=') {
opt = &qual_options[i];
s += n + 1;
break;
}
}
not = 0;
if (*s == '!') {
not = 1;
s++;
}
if (strcmp(s, "none") == 0) {
not = 1 - not;
s = "all";
}
if (strcmp(s, "all") == 0) {
for (i = 0; i < MAX_QUALS; i++) {
qualify_one(i, opt->bitflag, not, -1);
}
return;
}
for (i = 0; i < MAX_QUALS; i++) {
qualify_one(i, opt->bitflag, !not, -1);
}
if (!(copy = strdup(s))) {
fprintf(stderr, "out of memory\n");
exit(1);
}
for (p = strtok(copy, ","); p; p = strtok(NULL, ",")) {
if (opt->bitflag == QUAL_TRACE && (n = lookup_class(p)) > 0) {
for (i = 0; i < nsyscalls0; i++)
if (sysent0[i].sys_flags & n)
qualify_one(i, opt->bitflag, not, 0);
#if SUPPORTED_PERSONALITIES >= 2
for (i = 0; i < nsyscalls1; i++)
if (sysent1[i].sys_flags & n)
qualify_one(i, opt->bitflag, not, 1);
#endif /* SUPPORTED_PERSONALITIES >= 2 */
#if SUPPORTED_PERSONALITIES >= 3
for (i = 0; i < nsyscalls2; i++)
if (sysent2[i].sys_flags & n)
qualify_one(i, opt->bitflag, not, 2);
#endif /* SUPPORTED_PERSONALITIES >= 3 */
continue;
}
if (opt->qualify(p, opt->bitflag, not)) {
fprintf(stderr, "strace: invalid %s `%s'\n",
opt->argument_name, p);
exit(1);
}
}
free(copy);
return;
}
static void
dumpio(struct tcb *tcp)
{
if (syserror(tcp))
return;
if (tcp->u_arg[0] < 0 || tcp->u_arg[0] >= MAX_QUALS)
return;
if (tcp->scno < 0 || tcp->scno >= nsyscalls)
return;
if (sysent[tcp->scno].sys_func == printargs)
return;
if (qual_flags[tcp->u_arg[0]] & QUAL_READ) {
if (sysent[tcp->scno].sys_func == sys_read ||
sysent[tcp->scno].sys_func == sys_pread ||
sysent[tcp->scno].sys_func == sys_pread64 ||
sysent[tcp->scno].sys_func == sys_recv ||
sysent[tcp->scno].sys_func == sys_recvfrom)
dumpstr(tcp, tcp->u_arg[1], tcp->u_rval);
else if (sysent[tcp->scno].sys_func == sys_readv)
dumpiov(tcp, tcp->u_arg[2], tcp->u_arg[1]);
return;
}
if (qual_flags[tcp->u_arg[0]] & QUAL_WRITE) {
if (sysent[tcp->scno].sys_func == sys_write ||
sysent[tcp->scno].sys_func == sys_pwrite ||
sysent[tcp->scno].sys_func == sys_pwrite64 ||
sysent[tcp->scno].sys_func == sys_send ||
sysent[tcp->scno].sys_func == sys_sendto)
dumpstr(tcp, tcp->u_arg[1], tcp->u_arg[2]);
else if (sysent[tcp->scno].sys_func == sys_writev)
dumpiov(tcp, tcp->u_arg[2], tcp->u_arg[1]);
return;
}
}
#ifndef FREEBSD
enum subcall_style { shift_style, deref_style, mask_style, door_style };
#else /* FREEBSD */
enum subcall_style { shift_style, deref_style, mask_style, door_style, table_style };
struct subcall {
int call;
int nsubcalls;
int subcalls[5];
};
static const struct subcall subcalls_table[] = {
{ SYS_shmsys, 5, { SYS_shmat, SYS_shmctl, SYS_shmdt, SYS_shmget, SYS_shmctl } },
#ifdef SYS_semconfig
{ SYS_semsys, 4, { SYS___semctl, SYS_semget, SYS_semop, SYS_semconfig } },
#else
{ SYS_semsys, 3, { SYS___semctl, SYS_semget, SYS_semop } },
#endif
{ SYS_msgsys, 4, { SYS_msgctl, SYS_msgget, SYS_msgsnd, SYS_msgrcv } },
};
#endif /* FREEBSD */
#if !(defined(LINUX) && ( defined(ALPHA) || defined(MIPS) || defined(__ARM_EABI__) ))
static void
decode_subcall(tcp, subcall, nsubcalls, style)
struct tcb *tcp;
int subcall;
int nsubcalls;
enum subcall_style style;
{
unsigned long addr, mask;
int i;
int size = personality_wordsize[current_personality];
switch (style) {
case shift_style:
if (tcp->u_arg[0] < 0 || tcp->u_arg[0] >= nsubcalls)
return;
tcp->scno = subcall + tcp->u_arg[0];
if (sysent[tcp->scno].nargs != -1)
tcp->u_nargs = sysent[tcp->scno].nargs;
else
tcp->u_nargs--;
for (i = 0; i < tcp->u_nargs; i++)
tcp->u_arg[i] = tcp->u_arg[i + 1];
break;
case deref_style:
if (tcp->u_arg[0] < 0 || tcp->u_arg[0] >= nsubcalls)
return;
tcp->scno = subcall + tcp->u_arg[0];
addr = tcp->u_arg[1];
for (i = 0; i < sysent[tcp->scno].nargs; i++) {
if (size == sizeof(int)) {
unsigned int arg;
if (umove(tcp, addr, &arg) < 0)
arg = 0;
tcp->u_arg[i] = arg;
}
else if (size == sizeof(long)) {
unsigned long arg;
if (umove(tcp, addr, &arg) < 0)
arg = 0;
tcp->u_arg[i] = arg;
}
else
abort();
addr += size;
}
tcp->u_nargs = sysent[tcp->scno].nargs;
break;
case mask_style:
mask = (tcp->u_arg[0] >> 8) & 0xff;
for (i = 0; mask; i++)
mask >>= 1;
if (i >= nsubcalls)
return;
tcp->u_arg[0] &= 0xff;
tcp->scno = subcall + i;
if (sysent[tcp->scno].nargs != -1)
tcp->u_nargs = sysent[tcp->scno].nargs;
break;
case door_style:
/*
* Oh, yuck. The call code is the *sixth* argument.
* (don't you mean the *last* argument? - JH)
*/
if (tcp->u_arg[5] < 0 || tcp->u_arg[5] >= nsubcalls)
return;
tcp->scno = subcall + tcp->u_arg[5];
if (sysent[tcp->scno].nargs != -1)
tcp->u_nargs = sysent[tcp->scno].nargs;
else
tcp->u_nargs--;
break;
#ifdef FREEBSD
case table_style:
for (i = 0; i < sizeof(subcalls_table) / sizeof(struct subcall); i++)
if (subcalls_table[i].call == tcp->scno) break;
if (i < sizeof(subcalls_table) / sizeof(struct subcall) &&
tcp->u_arg[0] >= 0 && tcp->u_arg[0] < subcalls_table[i].nsubcalls) {
tcp->scno = subcalls_table[i].subcalls[tcp->u_arg[0]];
for (i = 0; i < tcp->u_nargs; i++)
tcp->u_arg[i] = tcp->u_arg[i + 1];
}
break;
#endif /* FREEBSD */
}
}
#endif
struct tcb *tcp_last = NULL;
static int
internal_syscall(struct tcb *tcp)
{
/*
* We must always trace a few critical system calls in order to
* correctly support following forks in the presence of tracing
* qualifiers.
*/
int (*func)();
if (tcp->scno < 0 || tcp->scno >= nsyscalls)
return 0;
func = sysent[tcp->scno].sys_func;
if (sys_exit == func)
return internal_exit(tcp);
if ( sys_fork == func
#if defined(FREEBSD) || defined(LINUX) || defined(SUNOS4)
|| sys_vfork == func
#endif
#ifdef LINUX
|| sys_clone == func
#endif
#if UNIXWARE > 2
|| sys_rfork == func
#endif
)
return internal_fork(tcp);
if ( sys_execve == func
#if defined(SPARC) || defined(SPARC64) || defined(SUNOS4)
|| sys_execv == func
#endif
#if UNIXWARE > 2
|| sys_rexecve == func
#endif
)
return internal_exec(tcp);
if ( sys_waitpid == func
|| sys_wait4 == func
#if defined(SVR4) || defined(FREEBSD) || defined(SUNOS4)
|| sys_wait == func
#endif
#ifdef ALPHA
|| sys_osf_wait4 == func
#endif
)
return internal_wait(tcp, 2);
#if defined(LINUX) || defined(SVR4)
if (sys_waitid == func)
return internal_wait(tcp, 3);
#endif
return 0;
}
#ifdef LINUX
#if defined (I386)
static long eax;
#elif defined (IA64)
long r8, r10, psr;
long ia32 = 0;
#elif defined (POWERPC)
static long result,flags;
#elif defined (M68K)
static long d0;
#elif defined(BFIN)
static long r0;
#elif defined (ARM)
static struct pt_regs regs;
#elif defined (ALPHA)
static long r0;
static long a3;
#elif defined(AVR32)
static struct pt_regs regs;
#elif defined (SPARC) || defined (SPARC64)
static struct pt_regs regs;
static unsigned long trap;
#elif defined(LINUX_MIPSN32)
static long long a3;
static long long r2;
#elif defined(MIPS)
static long a3;
static long r2;
#elif defined(S390) || defined(S390X)
static long gpr2;
static long pc;
static long syscall_mode;
#elif defined(HPPA)
static long r28;
#elif defined(SH)
static long r0;
#elif defined(SH64)
static long r9;
#elif defined(X86_64)
static long rax;
#elif defined(CRISV10) || defined(CRISV32)
static long r10;
#elif defined(MICROBLAZE)
static long r3;
#endif
#endif /* LINUX */
#ifdef FREEBSD
struct reg regs;
#endif /* FREEBSD */
int
get_scno(struct tcb *tcp)
{
long scno = 0;
#ifdef LINUX
# if defined(S390) || defined(S390X)
if (tcp->flags & TCB_WAITEXECVE) {
/*
* When the execve system call completes successfully, the
* new process still has -ENOSYS (old style) or __NR_execve
* (new style) in gpr2. We cannot recover the scno again
* by disassembly, because the image that executed the
* syscall is gone now. Fortunately, we don't want it. We
* leave the flag set so that syscall_fixup can fake the
* result.
*/
if (tcp->flags & TCB_INSYSCALL)
return 1;
/*
* This is the SIGTRAP after execve. We cannot try to read
* the system call here either.
*/
tcp->flags &= ~TCB_WAITEXECVE;
return 0;
}
if (upeek(tcp, PT_GPR2, &syscall_mode) < 0)
return -1;
if (syscall_mode != -ENOSYS) {
/*
* Since kernel version 2.5.44 the scno gets passed in gpr2.
*/
scno = syscall_mode;
} else {
/*
* Old style of "passing" the scno via the SVC instruction.
*/
long opcode, offset_reg, tmp;
void * svc_addr;
int gpr_offset[16] = {PT_GPR0, PT_GPR1, PT_ORIGGPR2, PT_GPR3,
PT_GPR4, PT_GPR5, PT_GPR6, PT_GPR7,
PT_GPR8, PT_GPR9, PT_GPR10, PT_GPR11,
PT_GPR12, PT_GPR13, PT_GPR14, PT_GPR15};
if (upeek(tcp, PT_PSWADDR, &pc) < 0)
return -1;
errno = 0;
opcode = ptrace(PTRACE_PEEKTEXT, tcp->pid, (char *)(pc-sizeof(long)), 0);
if (errno) {
perror("peektext(pc-oneword)");
return -1;
}
/*
* We have to check if the SVC got executed directly or via an
* EXECUTE instruction. In case of EXECUTE it is necessary to do
* instruction decoding to derive the system call number.
* Unfortunately the opcode sizes of EXECUTE and SVC are differently,
* so that this doesn't work if a SVC opcode is part of an EXECUTE
* opcode. Since there is no way to find out the opcode size this
* is the best we can do...
*/
if ((opcode & 0xff00) == 0x0a00) {
/* SVC opcode */
scno = opcode & 0xff;
}
else {
/* SVC got executed by EXECUTE instruction */
/*
* Do instruction decoding of EXECUTE. If you really want to
* understand this, read the Principles of Operations.
*/
svc_addr = (void *) (opcode & 0xfff);
tmp = 0;
offset_reg = (opcode & 0x000f0000) >> 16;
if (offset_reg && (upeek(tcp, gpr_offset[offset_reg], &tmp) < 0))
return -1;
svc_addr += tmp;
tmp = 0;
offset_reg = (opcode & 0x0000f000) >> 12;
if (offset_reg && (upeek(tcp, gpr_offset[offset_reg], &tmp) < 0))
return -1;
svc_addr += tmp;
scno = ptrace(PTRACE_PEEKTEXT, tcp->pid, svc_addr, 0);
if (errno)
return -1;
# if defined(S390X)
scno >>= 48;
# else
scno >>= 16;
# endif
tmp = 0;
offset_reg = (opcode & 0x00f00000) >> 20;
if (offset_reg && (upeek(tcp, gpr_offset[offset_reg], &tmp) < 0))
return -1;
scno = (scno | tmp) & 0xff;
}
}
# elif defined (POWERPC)
if (upeek(tcp, sizeof(unsigned long)*PT_R0, &scno) < 0)
return -1;
if (!(tcp->flags & TCB_INSYSCALL)) {
/* Check if we return from execve. */
if (scno == 0 && (tcp->flags & TCB_WAITEXECVE)) {
tcp->flags &= ~TCB_WAITEXECVE;
return 0;
}
}
# ifdef POWERPC64
if (!(tcp->flags & TCB_INSYSCALL)) {
static int currpers = -1;
long val;
int pid = tcp->pid;
/* Check for 64/32 bit mode. */
if (upeek(tcp, sizeof (unsigned long)*PT_MSR, &val) < 0)
return -1;
/* SF is bit 0 of MSR */
if (val < 0)
currpers = 0;
else
currpers = 1;
if (currpers != current_personality) {
static const char *const names[] = {"64 bit", "32 bit"};
set_personality(currpers);
fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
pid, names[current_personality]);
}
}
# endif
# elif defined(AVR32)
/*
* Read complete register set in one go.
*/
if (ptrace(PTRACE_GETREGS, tcp->pid, NULL, ®s) < 0)
return -1;
/*
* We only need to grab the syscall number on syscall entry.
*/
if (!(tcp->flags & TCB_INSYSCALL)) {
scno = regs.r8;
/* Check if we return from execve. */
if (tcp->flags & TCB_WAITEXECVE) {
tcp->flags &= ~TCB_WAITEXECVE;
return 0;
}
}
# elif defined(BFIN)
if (upeek(tcp, PT_ORIG_P0, &scno))
return -1;
# elif defined (I386)
if (upeek(tcp, 4*ORIG_EAX, &scno) < 0)
return -1;
# elif defined (X86_64)
if (upeek(tcp, 8*ORIG_RAX, &scno) < 0)
return -1;
if (!(tcp->flags & TCB_INSYSCALL)) {
static int currpers = -1;
long val;
int pid = tcp->pid;
/* Check CS register value. On x86-64 linux it is:
* 0x33 for long mode (64 bit)
* 0x23 for compatibility mode (32 bit)
* It takes only one ptrace and thus doesn't need
* to be cached.
*/
if (upeek(tcp, 8*CS, &val) < 0)
return -1;
switch (val) {
case 0x23: currpers = 1; break;
case 0x33: currpers = 0; break;
default:
fprintf(stderr, "Unknown value CS=0x%02X while "
"detecting personality of process "
"PID=%d\n", (int)val, pid);
currpers = current_personality;
break;
}
# if 0
/* This version analyzes the opcode of a syscall instruction.
* (int 0x80 on i386 vs. syscall on x86-64)
* It works, but is too complicated.
*/
unsigned long val, rip, i;
if (upeek(tcp, 8*RIP, &rip) < 0)
perror("upeek(RIP)");
/* sizeof(syscall) == sizeof(int 0x80) == 2 */
rip -= 2;
errno = 0;
call = ptrace(PTRACE_PEEKTEXT, pid, (char *)rip, (char *)0);
if (errno)
fprintf(stderr, "ptrace_peektext failed: %s\n",
strerror(errno));
switch (call & 0xffff) {
/* x86-64: syscall = 0x0f 0x05 */
case 0x050f: currpers = 0; break;
/* i386: int 0x80 = 0xcd 0x80 */
case 0x80cd: currpers = 1; break;
default:
currpers = current_personality;
fprintf(stderr,
"Unknown syscall opcode (0x%04X) while "
"detecting personality of process "
"PID=%d\n", (int)call, pid);
break;
}
# endif
if (currpers != current_personality) {
static const char *const names[] = {"64 bit", "32 bit"};
set_personality(currpers);
fprintf(stderr, "[ Process PID=%d runs in %s mode. ]\n",
pid, names[current_personality]);
}
}
# elif defined(IA64)
# define IA64_PSR_IS ((long)1 << 34)
if (upeek (tcp, PT_CR_IPSR, &psr) >= 0)
ia32 = (psr & IA64_PSR_IS) != 0;
if (!(tcp->flags & TCB_INSYSCALL)) {
if (ia32) {
if (upeek(tcp, PT_R1, &scno) < 0) /* orig eax */
return -1;
} else {
if (upeek (tcp, PT_R15, &scno) < 0)
return -1;
}
/* Check if we return from execve. */
if (tcp->flags & TCB_WAITEXECVE) {
tcp->flags &= ~TCB_WAITEXECVE;
return 0;
}
} else {
/* syscall in progress */
if (upeek (tcp, PT_R8, &r8) < 0)
return -1;
if (upeek (tcp, PT_R10, &r10) < 0)
return -1;
}
# elif defined (ARM)
/*
* Read complete register set in one go.
*/
if (ptrace(PTRACE_GETREGS, tcp->pid, NULL, (void *)®s) == -1)
return -1;
/*
* We only need to grab the syscall number on syscall entry.
*/
if (regs.ARM_ip == 0) {
if (!(tcp->flags & TCB_INSYSCALL)) {
/* Check if we return from execve. */
if (tcp->flags & TCB_WAITEXECVE) {