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
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
/*
* Preloader for ld.so
*
* Copyright (C) 1995,96,97,98,99,2000,2001,2002 Free Software Foundation, Inc.
* Copyright (C) 2004 Mike McCormack for CodeWeavers
* Copyright (C) 2004 Alexandre Julliard
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
*/
/*
* Design notes
*
* The goal of this program is to be a workaround for exec-shield, as used
* by the Linux kernel distributed with Fedora Core and other distros.
*
* To do this, we implement our own shared object loader that reserves memory
* that is important to Wine, and then loads the main binary and its ELF
* interpreter.
*
* We will try to set up the stack and memory area so that the program that
* loads after us (eg. the wine binary) never knows we were here, except that
* areas of memory it needs are already magically reserved.
*
* The following memory areas are important to Wine:
* 0x00000000 - 0x00110000 the DOS area
* 0x80000000 - 0x81000000 the shared heap
* ??? - ??? the PE binary load address (usually starting at 0x00400000)
*
* If this program is used as the shared object loader, the only difference
* that the loaded programs should see is that this loader will be mapped
* into memory when it starts.
*/
/*
* References (things I consulted to understand how ELF loading works):
*
* glibc 2.3.2 elf/dl-load.c
* http://www.gnu.org/directory/glibc.html
*
* Linux 2.6.4 fs/binfmt_elf.c
* ftp://ftp.kernel.org/pub/linux/kernel/v2.6/linux-2.6.4.tar.bz2
*
* Userland exec, by <grugq@hcunix.net>
* http://cert.uni-stuttgart.de/archive/bugtraq/2004/01/msg00002.html
*
* The ELF specification:
* http://www.linuxbase.org/spec/booksets/LSB-Embedded/LSB-Embedded/book387.html
*/
#include "config.h"
#include "wine/port.h"
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#ifdef HAVE_SYS_STAT_H
# include <sys/stat.h>
#endif
#include <fcntl.h>
#ifdef HAVE_SYS_MMAN_H
# include <sys/mman.h>
#endif
#ifdef HAVE_SYS_SYSCALL_H
# include <sys/syscall.h>
#endif
#ifdef HAVE_UNISTD_H
# include <unistd.h>
#endif
#ifdef HAVE_ELF_H
# include <elf.h>
#endif
#ifdef HAVE_LINK_H
# include <link.h>
#endif
#ifdef HAVE_SYS_LINK_H
# include <sys/link.h>
#endif
#include "main.h"
/* ELF definitions */
#define ELF_PREFERRED_ADDRESS(loader, maplength, mapstartpref) (mapstartpref)
#define ELF_FIXED_ADDRESS(loader, mapstart) ((void) 0)
#define MAP_BASE_ADDR(l) 0
#ifndef MAP_COPY
#define MAP_COPY MAP_PRIVATE
#endif
#ifndef MAP_NORESERVE
#define MAP_NORESERVE 0
#endif
static struct wine_preload_info preload_info[] =
{
{ (void *)0x00000000, 0x60000000 }, /* low memory area */
{ (void *)0x7f000000, 0x02000000 }, /* top-down allocations + shared heap */
{ 0, 0 }, /* PE exe range set with WINEPRELOADRESERVE */
{ 0, 0 } /* end of list */
};
/* debugging */
#undef DUMP_SEGMENTS
#undef DUMP_AUX_INFO
#undef DUMP_SYMS
/* older systems may not define these */
#ifndef PT_TLS
#define PT_TLS 7
#endif
#ifndef AT_SYSINFO
#define AT_SYSINFO 32
#endif
#ifndef AT_SYSINFO_EHDR
#define AT_SYSINFO_EHDR 33
#endif
#ifndef DT_GNU_HASH
#define DT_GNU_HASH 0x6ffffef5
#endif
static unsigned int page_size, page_mask;
static char *preloader_start, *preloader_end;
struct wld_link_map {
ElfW(Addr) l_addr;
ElfW(Dyn) *l_ld;
ElfW(Phdr)*l_phdr;
ElfW(Addr) l_entry;
ElfW(Half) l_ldnum;
ElfW(Half) l_phnum;
ElfW(Addr) l_map_start, l_map_end;
ElfW(Addr) l_interp;
};
/*
* The __bb_init_func is an empty function only called when file is
* compiled with gcc flags "-fprofile-arcs -ftest-coverage". This
* function is normally provided by libc's startup files, but since we
* build the preloader with "-nostartfiles -nodefaultlibs", we have to
* provide our own (empty) version, otherwise linker fails.
*/
void __bb_init_func(void) { return; }
/* similar to the above but for -fstack-protector */
void *__stack_chk_guard = 0;
void __stack_chk_fail(void) { return; }
/* data for setting up the glibc-style thread-local storage in %gs */
static int thread_data[256];
struct
{
/* this is the kernel modify_ldt struct */
unsigned int entry_number;
unsigned long base_addr;
unsigned int limit;
unsigned int seg_32bit : 1;
unsigned int contents : 2;
unsigned int read_exec_only : 1;
unsigned int limit_in_pages : 1;
unsigned int seg_not_present : 1;
unsigned int useable : 1;
unsigned int garbage : 25;
} thread_ldt = { -1, (unsigned long)thread_data, 0xfffff, 1, 0, 0, 1, 0, 1, 0 };
/*
* The _start function is the entry and exit point of this program
*
* It calls wld_start, passing a pointer to the args it receives
* then jumps to the address wld_start returns.
*/
void _start();
extern char _end[];
__ASM_GLOBAL_FUNC(_start,
"\tmovl $243,%eax\n" /* SYS_set_thread_area */
"\tmovl $thread_ldt,%ebx\n"
"\tint $0x80\n" /* allocate gs segment */
"\torl %eax,%eax\n"
"\tjl 1f\n"
"\tmovl thread_ldt,%eax\n" /* thread_ldt.entry_number */
"\tshl $3,%eax\n"
"\torl $3,%eax\n"
"\tmov %ax,%gs\n"
"\tmov %ax,%fs\n" /* set %fs too so libwine can retrieve it later on */
"1:\tmovl %esp,%eax\n"
"\tleal -136(%esp),%esp\n" /* allocate some space for extra aux values */
"\tpushl %eax\n" /* orig stack pointer */
"\tpushl %esp\n" /* ptr to orig stack pointer */
"\tcall wld_start\n"
"\tpopl %ecx\n" /* remove ptr to stack pointer */
"\tpopl %esp\n" /* new stack pointer */
"\tpush %eax\n" /* ELF interpreter entry point */
"\txor %eax,%eax\n"
"\txor %ecx,%ecx\n"
"\txor %edx,%edx\n"
"\tmov %ax,%gs\n" /* clear %gs again */
"\tret\n")
/* wrappers for Linux system calls */
#define SYSCALL_RET(ret) (((ret) < 0 && (ret) > -4096) ? -1 : (ret))
static inline __attribute__((noreturn)) void wld_exit( int code )
{
for (;;) /* avoid warning */
__asm__ __volatile__( "pushl %%ebx; movl %1,%%ebx; int $0x80; popl %%ebx"
: : "a" (SYS_exit), "r" (code) );
}
static inline int wld_open( const char *name, int flags )
{
int ret;
__asm__ __volatile__( "pushl %%ebx; movl %2,%%ebx; int $0x80; popl %%ebx"
: "=a" (ret) : "0" (SYS_open), "r" (name), "c" (flags) );
return SYSCALL_RET(ret);
}
static inline int wld_close( int fd )
{
int ret;
__asm__ __volatile__( "pushl %%ebx; movl %2,%%ebx; int $0x80; popl %%ebx"
: "=a" (ret) : "0" (SYS_close), "r" (fd) );
return SYSCALL_RET(ret);
}
static inline ssize_t wld_read( int fd, void *buffer, size_t len )
{
int ret;
__asm__ __volatile__( "pushl %%ebx; movl %2,%%ebx; int $0x80; popl %%ebx"
: "=a" (ret)
: "0" (SYS_read), "r" (fd), "c" (buffer), "d" (len)
: "memory" );
return SYSCALL_RET(ret);
}
static inline ssize_t wld_write( int fd, const void *buffer, size_t len )
{
int ret;
__asm__ __volatile__( "pushl %%ebx; movl %2,%%ebx; int $0x80; popl %%ebx"
: "=a" (ret) : "0" (SYS_write), "r" (fd), "c" (buffer), "d" (len) );
return SYSCALL_RET(ret);
}
static inline int wld_mprotect( const void *addr, size_t len, int prot )
{
int ret;
__asm__ __volatile__( "pushl %%ebx; movl %2,%%ebx; int $0x80; popl %%ebx"
: "=a" (ret) : "0" (SYS_mprotect), "r" (addr), "c" (len), "d" (prot) );
return SYSCALL_RET(ret);
}
static void *wld_mmap( void *start, size_t len, int prot, int flags, int fd, off_t offset )
{
int ret;
struct
{
void *addr;
unsigned int length;
unsigned int prot;
unsigned int flags;
unsigned int fd;
unsigned int offset;
} args;
args.addr = start;
args.length = len;
args.prot = prot;
args.flags = flags;
args.fd = fd;
args.offset = offset;
__asm__ __volatile__( "pushl %%ebx; movl %2,%%ebx; int $0x80; popl %%ebx"
: "=a" (ret) : "0" (SYS_mmap), "q" (&args) : "memory" );
return (void *)SYSCALL_RET(ret);
}
static inline uid_t wld_getuid(void)
{
uid_t ret;
__asm__( "int $0x80" : "=a" (ret) : "0" (SYS_getuid) );
return ret;
}
static inline uid_t wld_geteuid(void)
{
uid_t ret;
__asm__( "int $0x80" : "=a" (ret) : "0" (SYS_geteuid) );
return ret;
}
static inline gid_t wld_getgid(void)
{
gid_t ret;
__asm__( "int $0x80" : "=a" (ret) : "0" (SYS_getgid) );
return ret;
}
static inline gid_t wld_getegid(void)
{
gid_t ret;
__asm__( "int $0x80" : "=a" (ret) : "0" (SYS_getegid) );
return ret;
}
static inline int wld_prctl( int code, int arg )
{
int ret;
__asm__ __volatile__( "pushl %%ebx; movl %2,%%ebx; int $0x80; popl %%ebx"
: "=a" (ret) : "0" (SYS_prctl), "r" (code), "c" (arg) );
return SYSCALL_RET(ret);
}
/* replacement for libc functions */
static int wld_strcmp( const char *str1, const char *str2 )
{
while (*str1 && (*str1 == *str2)) { str1++; str2++; }
return *str1 - *str2;
}
static int wld_strncmp( const char *str1, const char *str2, size_t len )
{
if (len <= 0) return 0;
while ((--len > 0) && *str1 && (*str1 == *str2)) { str1++; str2++; }
return *str1 - *str2;
}
static inline void *wld_memset( void *dest, int val, size_t len )
{
char *dst = dest;
while (len--) *dst++ = val;
return dest;
}
/*
* wld_printf - just the basics
*
* %x prints a hex number
* %s prints a string
* %p prints a pointer
*/
static int wld_vsprintf(char *buffer, const char *fmt, va_list args )
{
static const char hex_chars[16] = "0123456789abcdef";
const char *p = fmt;
char *str = buffer;
int i;
while( *p )
{
if( *p == '%' )
{
p++;
if( *p == 'x' )
{
unsigned int x = va_arg( args, unsigned int );
for(i=7; i>=0; i--)
*str++ = hex_chars[(x>>(i*4))&0xf];
}
else if (p[0] == 'l' && p[1] == 'x')
{
unsigned long x = va_arg( args, unsigned long );
for(i=7; i>=0; i--)
*str++ = hex_chars[(x>>(i*4))&0xf];
p++;
}
else if( *p == 'p' )
{
unsigned long x = (unsigned long)va_arg( args, void * );
for(i=7; i>=0; i--)
*str++ = hex_chars[(x>>(i*4))&0xf];
}
else if( *p == 's' )
{
char *s = va_arg( args, char * );
while(*s)
*str++ = *s++;
}
else if( *p == 0 )
break;
p++;
}
*str++ = *p++;
}
*str = 0;
return str - buffer;
}
static __attribute__((format(printf,1,2))) void wld_printf(const char *fmt, ... )
{
va_list args;
char buffer[256];
int len;
va_start( args, fmt );
len = wld_vsprintf(buffer, fmt, args );
va_end( args );
wld_write(2, buffer, len);
}
static __attribute__((noreturn,format(printf,1,2))) void fatal_error(const char *fmt, ... )
{
va_list args;
char buffer[256];
int len;
va_start( args, fmt );
len = wld_vsprintf(buffer, fmt, args );
va_end( args );
wld_write(2, buffer, len);
wld_exit(1);
}
#ifdef DUMP_AUX_INFO
/*
* Dump interesting bits of the ELF auxv_t structure that is passed
* as the 4th parameter to the _start function
*/
static void dump_auxiliary( ElfW(auxv_t) *av )
{
#define NAME(at) { at, #at }
static const struct { int val; const char *name; } names[] =
{
NAME(AT_BASE),
NAME(AT_CLKTCK),
NAME(AT_EGID),
NAME(AT_ENTRY),
NAME(AT_EUID),
NAME(AT_FLAGS),
NAME(AT_GID),
NAME(AT_HWCAP),
NAME(AT_PAGESZ),
NAME(AT_PHDR),
NAME(AT_PHENT),
NAME(AT_PHNUM),
NAME(AT_PLATFORM),
NAME(AT_SYSINFO),
NAME(AT_SYSINFO_EHDR),
NAME(AT_UID),
{ 0, NULL }
};
#undef NAME
int i;
for ( ; av->a_type != AT_NULL; av++)
{
for (i = 0; names[i].name; i++) if (names[i].val == av->a_type) break;
if (names[i].name) wld_printf("%s = %lx\n", names[i].name, av->a_un.a_val);
else wld_printf( "%x = %lx\n", av->a_type, av->a_un.a_val );
}
}
#endif
/*
* set_auxiliary_values
*
* Set the new auxiliary values
*/
static void set_auxiliary_values( ElfW(auxv_t) *av, const ElfW(auxv_t) *new_av,
const ElfW(auxv_t) *delete_av, void **stack )
{
int i, j, av_count = 0, new_count = 0, delete_count = 0;
char *src, *dst;
/* count how many aux values we have already */
while (av[av_count].a_type != AT_NULL) av_count++;
/* delete unwanted values */
for (j = 0; delete_av[j].a_type != AT_NULL; j++)
{
for (i = 0; i < av_count; i++) if (av[i].a_type == delete_av[j].a_type)
{
av[i].a_type = av[av_count-1].a_type;
av[i].a_un.a_val = av[av_count-1].a_un.a_val;
av[--av_count].a_type = AT_NULL;
delete_count++;
break;
}
}
/* count how many values we have in new_av that aren't in av */
for (j = 0; new_av[j].a_type != AT_NULL; j++)
{
for (i = 0; i < av_count; i++) if (av[i].a_type == new_av[j].a_type) break;
if (i == av_count) new_count++;
}
src = (char *)*stack;
dst = src - (new_count - delete_count) * sizeof(*av);
if (new_count > delete_count) /* need to make room for the extra values */
{
int len = (char *)(av + av_count + 1) - src;
for (i = 0; i < len; i++) dst[i] = src[i];
}
else if (new_count < delete_count) /* get rid of unused values */
{
int len = (char *)(av + av_count + 1) - dst;
for (i = len - 1; i >= 0; i--) dst[i] = src[i];
}
*stack = dst;
av -= (new_count - delete_count);
/* now set the values */
for (j = 0; new_av[j].a_type != AT_NULL; j++)
{
for (i = 0; i < av_count; i++) if (av[i].a_type == new_av[j].a_type) break;
if (i < av_count) av[i].a_un.a_val = new_av[j].a_un.a_val;
else
{
av[av_count].a_type = new_av[j].a_type;
av[av_count].a_un.a_val = new_av[j].a_un.a_val;
av_count++;
}
}
#ifdef DUMP_AUX_INFO
wld_printf("New auxiliary info:\n");
dump_auxiliary( av );
#endif
}
/*
* get_auxiliary
*
* Get a field of the auxiliary structure
*/
static int get_auxiliary( ElfW(auxv_t) *av, int type, int def_val )
{
for ( ; av->a_type != AT_NULL; av++)
if( av->a_type == type ) return av->a_un.a_val;
return def_val;
}
/*
* map_so_lib
*
* modelled after _dl_map_object_from_fd() from glibc-2.3.1/elf/dl-load.c
*
* This function maps the segments from an ELF object, and optionally
* stores information about the mapping into the auxv_t structure.
*/
static void map_so_lib( const char *name, struct wld_link_map *l)
{
int fd;
unsigned char buf[0x800];
ElfW(Ehdr) *header = (ElfW(Ehdr)*)buf;
ElfW(Phdr) *phdr, *ph;
/* Scan the program header table, collecting its load commands. */
struct loadcmd
{
ElfW(Addr) mapstart, mapend, dataend, allocend;
off_t mapoff;
int prot;
} loadcmds[16], *c;
size_t nloadcmds = 0, maplength;
fd = wld_open( name, O_RDONLY );
if (fd == -1) fatal_error("%s: could not open\n", name );
if (wld_read( fd, buf, sizeof(buf) ) != sizeof(buf))
fatal_error("%s: failed to read ELF header\n", name);
phdr = (void*) (((unsigned char*)buf) + header->e_phoff);
if( ( header->e_ident[0] != 0x7f ) ||
( header->e_ident[1] != 'E' ) ||
( header->e_ident[2] != 'L' ) ||
( header->e_ident[3] != 'F' ) )
fatal_error( "%s: not an ELF binary... don't know how to load it\n", name );
if( header->e_machine != EM_386 )
fatal_error("%s: not an i386 ELF binary... don't know how to load it\n", name );
if (header->e_phnum > sizeof(loadcmds)/sizeof(loadcmds[0]))
fatal_error( "%s: oops... not enough space for load commands\n", name );
maplength = header->e_phnum * sizeof (ElfW(Phdr));
if (header->e_phoff + maplength > sizeof(buf))
fatal_error( "%s: oops... not enough space for ELF headers\n", name );
l->l_ld = 0;
l->l_addr = 0;
l->l_phdr = 0;
l->l_phnum = header->e_phnum;
l->l_entry = header->e_entry;
l->l_interp = 0;
for (ph = phdr; ph < &phdr[l->l_phnum]; ++ph)
{
#ifdef DUMP_SEGMENTS
wld_printf( "ph = %p\n", ph );
wld_printf( " p_type = %x\n", ph->p_type );
wld_printf( " p_flags = %x\n", ph->p_flags );
wld_printf( " p_offset = %x\n", ph->p_offset );
wld_printf( " p_vaddr = %x\n", ph->p_vaddr );
wld_printf( " p_paddr = %x\n", ph->p_paddr );
wld_printf( " p_filesz = %x\n", ph->p_filesz );
wld_printf( " p_memsz = %x\n", ph->p_memsz );
wld_printf( " p_align = %x\n", ph->p_align );
#endif
switch (ph->p_type)
{
/* These entries tell us where to find things once the file's
segments are mapped in. We record the addresses it says
verbatim, and later correct for the run-time load address. */
case PT_DYNAMIC:
l->l_ld = (void *) ph->p_vaddr;
l->l_ldnum = ph->p_memsz / sizeof (Elf32_Dyn);
break;
case PT_PHDR:
l->l_phdr = (void *) ph->p_vaddr;
break;
case PT_LOAD:
{
if ((ph->p_align & page_mask) != 0)
fatal_error( "%s: ELF load command alignment not page-aligned\n", name );
if (((ph->p_vaddr - ph->p_offset) & (ph->p_align - 1)) != 0)
fatal_error( "%s: ELF load command address/offset not properly aligned\n", name );
c = &loadcmds[nloadcmds++];
c->mapstart = ph->p_vaddr & ~(ph->p_align - 1);
c->mapend = ((ph->p_vaddr + ph->p_filesz + page_mask) & ~page_mask);
c->dataend = ph->p_vaddr + ph->p_filesz;
c->allocend = ph->p_vaddr + ph->p_memsz;
c->mapoff = ph->p_offset & ~(ph->p_align - 1);
c->prot = 0;
if (ph->p_flags & PF_R)
c->prot |= PROT_READ;
if (ph->p_flags & PF_W)
c->prot |= PROT_WRITE;
if (ph->p_flags & PF_X)
c->prot |= PROT_EXEC;
}
break;
case PT_INTERP:
l->l_interp = ph->p_vaddr;
break;
case PT_TLS:
/*
* We don't need to set anything up because we're
* emulating the kernel, not ld-linux.so.2
* The ELF loader will set up the TLS data itself.
*/
case PT_SHLIB:
case PT_NOTE:
default:
break;
}
}
/* Now process the load commands and map segments into memory. */
c = loadcmds;
/* Length of the sections to be loaded. */
maplength = loadcmds[nloadcmds - 1].allocend - c->mapstart;
if( header->e_type == ET_DYN )
{
ElfW(Addr) mappref;
mappref = (ELF_PREFERRED_ADDRESS (loader, maplength, c->mapstart)
- MAP_BASE_ADDR (l));
/* Remember which part of the address space this object uses. */
l->l_map_start = (ElfW(Addr)) wld_mmap ((void *) mappref, maplength,
c->prot, MAP_COPY | MAP_FILE,
fd, c->mapoff);
/* wld_printf("set : offset = %x\n", c->mapoff); */
/* wld_printf("l->l_map_start = %x\n", l->l_map_start); */
l->l_map_end = l->l_map_start + maplength;
l->l_addr = l->l_map_start - c->mapstart;
wld_mprotect ((caddr_t) (l->l_addr + c->mapend),
loadcmds[nloadcmds - 1].allocend - c->mapend,
PROT_NONE);
goto postmap;
}
else
{
/* sanity check */
if ((char *)c->mapstart + maplength > preloader_start &&
(char *)c->mapstart <= preloader_end)
fatal_error( "%s: binary overlaps preloader (%p-%p)\n",
name, (char *)c->mapstart, (char *)c->mapstart + maplength );
ELF_FIXED_ADDRESS (loader, c->mapstart);
}
/* Remember which part of the address space this object uses. */
l->l_map_start = c->mapstart + l->l_addr;
l->l_map_end = l->l_map_start + maplength;
while (c < &loadcmds[nloadcmds])
{
if (c->mapend > c->mapstart)
/* Map the segment contents from the file. */
wld_mmap ((void *) (l->l_addr + c->mapstart),
c->mapend - c->mapstart, c->prot,
MAP_FIXED | MAP_COPY | MAP_FILE, fd, c->mapoff);
postmap:
if (l->l_phdr == 0
&& (ElfW(Off)) c->mapoff <= header->e_phoff
&& ((size_t) (c->mapend - c->mapstart + c->mapoff)
>= header->e_phoff + header->e_phnum * sizeof (ElfW(Phdr))))
/* Found the program header in this segment. */
l->l_phdr = (void *)(unsigned int) (c->mapstart + header->e_phoff - c->mapoff);
if (c->allocend > c->dataend)
{
/* Extra zero pages should appear at the end of this segment,
after the data mapped from the file. */
ElfW(Addr) zero, zeroend, zeropage;
zero = l->l_addr + c->dataend;
zeroend = l->l_addr + c->allocend;
zeropage = (zero + page_mask) & ~page_mask;
/*
* This is different from the dl-load load...
* ld-linux.so.2 relies on the whole page being zero'ed
*/
zeroend = (zeroend + page_mask) & ~page_mask;
if (zeroend < zeropage)
{
/* All the extra data is in the last page of the segment.
We can just zero it. */
zeropage = zeroend;
}
if (zeropage > zero)
{
/* Zero the final part of the last page of the segment. */
if ((c->prot & PROT_WRITE) == 0)
{
/* Dag nab it. */
wld_mprotect ((caddr_t) (zero & ~page_mask), page_size, c->prot|PROT_WRITE);
}
wld_memset ((void *) zero, '\0', zeropage - zero);
if ((c->prot & PROT_WRITE) == 0)
wld_mprotect ((caddr_t) (zero & ~page_mask), page_size, c->prot);
}
if (zeroend > zeropage)
{
/* Map the remaining zero pages in from the zero fill FD. */
caddr_t mapat;
mapat = wld_mmap ((caddr_t) zeropage, zeroend - zeropage,
c->prot, MAP_ANON|MAP_PRIVATE|MAP_FIXED,
-1, 0);
}
}
++c;
}
if (l->l_phdr == NULL) fatal_error("no program header\n");
l->l_phdr = (void *)((ElfW(Addr))l->l_phdr + l->l_addr);
l->l_entry += l->l_addr;
wld_close( fd );
}
static unsigned int elf_hash( const char *name )
{
unsigned int hi, hash = 0;
while (*name)
{
hash = (hash << 4) + (unsigned char)*name++;
hi = hash & 0xf0000000;
hash ^= hi;
hash ^= hi >> 24;
}
return hash;
}
static unsigned int gnu_hash( const char *name )
{
unsigned int h = 5381;
while (*name) h = h * 33 + (unsigned char)*name++;
return h;
}
/*
* Find a symbol in the symbol table of the executable loaded
*/
static void *find_symbol( const ElfW(Phdr) *phdr, int num, const char *var, int type )
{
const ElfW(Dyn) *dyn = NULL;
const ElfW(Phdr) *ph;
const ElfW(Sym) *symtab = NULL;
const Elf_Symndx *hashtab = NULL;
const Elf32_Word *gnu_hashtab = NULL;
const char *strings = NULL;
Elf_Symndx idx;
/* check the values */
#ifdef DUMP_SYMS
wld_printf("%p %x\n", phdr, num );
#endif
if( ( phdr == NULL ) || ( num == 0 ) )
{
wld_printf("could not find PT_DYNAMIC header entry\n");
return NULL;
}
/* parse the (already loaded) ELF executable's header */
for (ph = phdr; ph < &phdr[num]; ++ph)
{
if( PT_DYNAMIC == ph->p_type )
{
dyn = (void *) ph->p_vaddr;
num = ph->p_memsz / sizeof (Elf32_Dyn);
break;
}
}
if( !dyn ) return NULL;
while( dyn->d_tag )
{
if( dyn->d_tag == DT_STRTAB )
strings = (const char*) dyn->d_un.d_ptr;
if( dyn->d_tag == DT_SYMTAB )
symtab = (const ElfW(Sym) *)dyn->d_un.d_ptr;
if( dyn->d_tag == DT_HASH )
hashtab = (const Elf_Symndx *)dyn->d_un.d_ptr;
if( dyn->d_tag == DT_GNU_HASH )
gnu_hashtab = (const Elf32_Word *)dyn->d_un.d_ptr;
#ifdef DUMP_SYMS
wld_printf("%x %x\n", dyn->d_tag, dyn->d_un.d_ptr );
#endif
dyn++;
}
if( (!symtab) || (!strings) ) return NULL;
if (gnu_hashtab) /* new style hash table */
{
const unsigned int hash = gnu_hash(var);
const Elf32_Word nbuckets = gnu_hashtab[0];
const Elf32_Word symbias = gnu_hashtab[1];
const Elf32_Word nwords = gnu_hashtab[2];
const ElfW(Addr) *bitmask = (const ElfW(Addr) *)(gnu_hashtab + 4);
const Elf32_Word *buckets = (const Elf32_Word *)(bitmask + nwords);
const Elf32_Word *chains = buckets + nbuckets - symbias;
if (!(idx = buckets[hash % nbuckets])) return NULL;
do
{
if ((chains[idx] & ~1u) == (hash & ~1u) &&
symtab[idx].st_info == ELF32_ST_INFO( STB_GLOBAL, type ) &&
!wld_strcmp( strings + symtab[idx].st_name, var ))
goto found;
} while (!(chains[idx++] & 1u));
}
else if (hashtab) /* old style hash table */
{
const unsigned int hash = elf_hash(var);
const Elf_Symndx nbuckets = hashtab[0];
const Elf_Symndx *buckets = hashtab + 2;
const Elf_Symndx *chains = buckets + nbuckets;
for (idx = buckets[hash % nbuckets]; idx != STN_UNDEF; idx = chains[idx])
{
if (symtab[idx].st_info == ELF32_ST_INFO( STB_GLOBAL, type ) &&
!wld_strcmp( strings + symtab[idx].st_name, var ))
goto found;
}
}
return NULL;
found:
#ifdef DUMP_SYMS
wld_printf("Found %s -> %x\n", strings + symtab[idx].st_name, symtab[idx].st_value );
#endif
return (void *)symtab[idx].st_value;
}
/*
* preload_reserve
*
* Reserve a range specified in string format
*/
static void preload_reserve( const char *str )
{
const char *p;
unsigned long result = 0;
void *start = NULL, *end = NULL;
int first = 1;
for (p = str; *p; p++)
{
if (*p >= '0' && *p <= '9') result = result * 16 + *p - '0';
else if (*p >= 'a' && *p <= 'f') result = result * 16 + *p - 'a' + 10;
else if (*p >= 'A' && *p <= 'F') result = result * 16 + *p - 'A' + 10;
else if (*p == '-')
{
if (!first) goto error;
start = (void *)(result & ~page_mask);
result = 0;
first = 0;
}
else goto error;
}
if (!first) end = (void *)((result + page_mask) & ~page_mask);
else if (result) goto error; /* single value '0' is allowed */
/* sanity checks */
if (end <= start) start = end = NULL;
else if ((char *)end > preloader_start &&
(char *)start <= preloader_end)
{
wld_printf( "WINEPRELOADRESERVE range %p-%p overlaps preloader %p-%p\n",
start, end, preloader_start, preloader_end );
start = end = NULL;
}
/* check for overlap with low memory area */
if ((char *)end <= (char *)preload_info[0].addr + preload_info[0].size)
start = end = NULL;
else if ((char *)start < (char *)preload_info[0].addr + preload_info[0].size)
start = (char *)preload_info[0].addr + preload_info[0].size;
/* entry 2 is for the PE exe */
preload_info[2].addr = start;
preload_info[2].size = (char *)end - (char *)start;
return;
error:
fatal_error( "invalid WINEPRELOADRESERVE value '%s'\n", str );
}
/* check if address is in one of the reserved ranges */
static int is_addr_reserved( const void *addr )
{
int i;
for (i = 0; preload_info[i].size; i++)
{
if ((const char *)addr >= (const char *)preload_info[i].addr &&
(const char *)addr < (const char *)preload_info[i].addr + preload_info[i].size)
return 1;
}
return 0;
}
/* remove a range from the preload list */
static void remove_preload_range( int i )
{
while (preload_info[i].size)
{
preload_info[i].addr = preload_info[i+1].addr;
preload_info[i].size = preload_info[i+1].size;
i++;
}
}
/*
* is_in_preload_range
*
* Check if address of the given aux value is in one of the reserved ranges
*/
static int is_in_preload_range( const ElfW(auxv_t) *av, int type )
{
while (av->a_type != AT_NULL)
{
if (av->a_type == type) return is_addr_reserved( (const void *)av->a_un.a_val );
av++;
}
return 0;
}
/* set the process name if supported */
static void set_process_name( int argc, char *argv[] )
{
unsigned int i, off;
char *p, *name, *end;
/* set the process short name */
for (p = name = argv[1]; *p; p++) if (p[0] == '/' && p[1]) name = p + 1;
if (wld_prctl( 15 /* PR_SET_NAME */, (int)name ) == -1) return;
/* find the end of the argv array and move everything down */
end = argv[argc - 1];
while (*end) end++;
off = argv[1] - argv[0];
for (p = argv[1]; p <= end; p++) *(p - off) = *p;
wld_memset( end - off, 0, off );
for (i = 1; i < argc; i++) argv[i] -= off;
}
/*
* wld_start
*
* Repeat the actions the kernel would do when loading a dynamically linked .so
* Load the binary and then its ELF interpreter.
* Note, we assume that the binary is a dynamically linked ELF shared object.
*/
void* wld_start( void **stack )
{
int i, *pargc;
char **argv, **p;
char *interp, *reserve = NULL;
ElfW(auxv_t) new_av[12], delete_av[3], *av;
struct wld_link_map main_binary_map, ld_so_map;
struct wine_preload_info **wine_main_preload_info;
pargc = *stack;
argv = (char **)pargc + 1;
if (*pargc < 2) fatal_error( "Usage: %s wine_binary [args]\n", argv[0] );
/* skip over the parameters */
p = argv + *pargc + 1;
/* skip over the environment */
while (*p)
{
static const char res[] = "WINEPRELOADRESERVE=";
if (!wld_strncmp( *p, res, sizeof(res)-1 )) reserve = *p + sizeof(res) - 1;
p++;
}
av = (ElfW(auxv_t)*) (p+1);
page_size = get_auxiliary( av, AT_PAGESZ, 4096 );
page_mask = page_size - 1;
preloader_start = (char *)_start - ((unsigned int)_start & page_mask);
preloader_end = (char *)((unsigned int)(_end + page_mask) & ~page_mask);
#ifdef DUMP_AUX_INFO
wld_printf( "stack = %p\n", *stack );
for( i = 0; i < *pargc; i++ ) wld_printf("argv[%x] = %s\n", i, argv[i]);
dump_auxiliary( av );
#endif
/* reserve memory that Wine needs */
if (reserve) preload_reserve( reserve );
for (i = 0; preload_info[i].size; i++)
{
if (wld_mmap( preload_info[i].addr, preload_info[i].size, PROT_NONE,
MAP_FIXED | MAP_PRIVATE | MAP_ANON | MAP_NORESERVE, -1, 0 ) == (void *)-1)
{
wld_printf( "preloader: Warning: failed to reserve range %p-%p\n",
preload_info[i].addr, (char *)preload_info[i].addr + preload_info[i].size );
remove_preload_range( i );
i--;
}
}
/* add an executable page at the top of the address space to defeat
* broken no-exec protections that play with the code selector limit */
if (is_addr_reserved( (char *)0x80000000 - page_size ))
wld_mprotect( (char *)0x80000000 - page_size, page_size, PROT_EXEC | PROT_READ );
/* load the main binary */
map_so_lib( argv[1], &main_binary_map );
/* load the ELF interpreter */
interp = (char *)main_binary_map.l_addr + main_binary_map.l_interp;
map_so_lib( interp, &ld_so_map );
/* store pointer to the preload info into the appropriate main binary variable */
wine_main_preload_info = find_symbol( main_binary_map.l_phdr, main_binary_map.l_phnum,
"wine_main_preload_info", STT_OBJECT );
if (wine_main_preload_info) *wine_main_preload_info = preload_info;
else wld_printf( "wine_main_preload_info not found\n" );
#define SET_NEW_AV(n,type,val) new_av[n].a_type = (type); new_av[n].a_un.a_val = (val);
SET_NEW_AV( 0, AT_PHDR, (unsigned long)main_binary_map.l_phdr );
SET_NEW_AV( 1, AT_PHENT, sizeof(ElfW(Phdr)) );
SET_NEW_AV( 2, AT_PHNUM, main_binary_map.l_phnum );
SET_NEW_AV( 3, AT_PAGESZ, page_size );
SET_NEW_AV( 4, AT_BASE, ld_so_map.l_addr );
SET_NEW_AV( 5, AT_FLAGS, get_auxiliary( av, AT_FLAGS, 0 ) );
SET_NEW_AV( 6, AT_ENTRY, main_binary_map.l_entry );
SET_NEW_AV( 7, AT_UID, get_auxiliary( av, AT_UID, wld_getuid() ) );
SET_NEW_AV( 8, AT_EUID, get_auxiliary( av, AT_EUID, wld_geteuid() ) );
SET_NEW_AV( 9, AT_GID, get_auxiliary( av, AT_GID, wld_getgid() ) );
SET_NEW_AV(10, AT_EGID, get_auxiliary( av, AT_EGID, wld_getegid() ) );
SET_NEW_AV(11, AT_NULL, 0 );
#undef SET_NEW_AV
i = 0;
/* delete sysinfo values if addresses conflict */
if (is_in_preload_range( av, AT_SYSINFO ) || is_in_preload_range( av, AT_SYSINFO_EHDR ))
{
delete_av[i++].a_type = AT_SYSINFO;
delete_av[i++].a_type = AT_SYSINFO_EHDR;
}
delete_av[i].a_type = AT_NULL;
/* get rid of first argument */
set_process_name( *pargc, argv );
pargc[1] = pargc[0] - 1;
*stack = pargc + 1;
set_auxiliary_values( av, new_av, delete_av, stack );
#ifdef DUMP_AUX_INFO
wld_printf("new stack = %p\n", *stack);
wld_printf("jumping to %x\n", ld_so_map.l_entry);
#endif
return (void *)ld_so_map.l_entry;
}