1 /*
2 * Preloader for ld.so
3 *
4 * Copyright (C) 1995,96,97,98,99,2000,2001,2002 Free Software Foundation, Inc.
5 * Copyright (C) 2004 Mike McCormack for CodeWeavers
6 * Copyright (C) 2004 Alexandre Julliard
7 *
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with this library; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
21 */
22
23 /*
24 * Design notes
25 *
26 * The goal of this program is to be a workaround for exec-shield, as used
27 * by the Linux kernel distributed with Fedora Core and other distros.
28 *
29 * To do this, we implement our own shared object loader that reserves memory
30 * that is important to Wine, and then loads the main binary and its ELF
31 * interpreter.
32 *
33 * We will try to set up the stack and memory area so that the program that
34 * loads after us (eg. the wine binary) never knows we were here, except that
35 * areas of memory it needs are already magically reserved.
36 *
37 * The following memory areas are important to Wine:
38 * 0x00000000 - 0x00110000 the DOS area
39 * 0x80000000 - 0x81000000 the shared heap
40 * ??? - ??? the PE binary load address (usually starting at 0x00400000)
41 *
42 * If this program is used as the shared object loader, the only difference
43 * that the loaded programs should see is that this loader will be mapped
44 * into memory when it starts.
45 */
46
47 /*
48 * References (things I consulted to understand how ELF loading works):
49 *
50 * glibc 2.3.2 elf/dl-load.c
51 * http://www.gnu.org/directory/glibc.html
52 *
53 * Linux 2.6.4 fs/binfmt_elf.c
54 * ftp://ftp.kernel.org/pub/linux/kernel/v2.6/linux-2.6.4.tar.bz2
55 *
56 * Userland exec, by <grugq@hcunix.net>
57 * http://cert.uni-stuttgart.de/archive/bugtraq/2004/01/msg00002.html
58 *
59 * The ELF specification:
60 * http://www.linuxbase.org/spec/booksets/LSB-Embedded/LSB-Embedded/book387.html
61 */
62
63 #include "config.h"
64 #include "wine/port.h"
65
66 #include <stdarg.h>
67 #include <stdio.h>
68 #include <stdlib.h>
69 #include <string.h>
70 #include <sys/types.h>
71 #ifdef HAVE_SYS_STAT_H
72 # include <sys/stat.h>
73 #endif
74 #include <fcntl.h>
75 #ifdef HAVE_SYS_MMAN_H
76 # include <sys/mman.h>
77 #endif
78 #ifdef HAVE_SYS_SYSCALL_H
79 # include <sys/syscall.h>
80 #endif
81 #ifdef HAVE_UNISTD_H
82 # include <unistd.h>
83 #endif
84 #ifdef HAVE_ELF_H
85 # include <elf.h>
86 #endif
87 #ifdef HAVE_LINK_H
88 # include <link.h>
89 #endif
90 #ifdef HAVE_SYS_LINK_H
91 # include <sys/link.h>
92 #endif
93
94 #include "main.h"
95
96 /* ELF definitions */
97 #define ELF_PREFERRED_ADDRESS(loader, maplength, mapstartpref) (mapstartpref)
98 #define ELF_FIXED_ADDRESS(loader, mapstart) ((void) 0)
99
100 #define MAP_BASE_ADDR(l) 0
101
102 #ifndef MAP_COPY
103 #define MAP_COPY MAP_PRIVATE
104 #endif
105 #ifndef MAP_NORESERVE
106 #define MAP_NORESERVE 0
107 #endif
108
109 static struct wine_preload_info preload_info[] =
110 {
111 { (void *)0x00000000, 0x00010000 }, /* low 64k */
112 { (void *)0x00010000, 0x00100000 }, /* DOS area */
113 { (void *)0x00110000, 0x5fef0000 }, /* low memory area */
114 { (void *)0x7f000000, 0x02000000 }, /* top-down allocations + shared heap */
115 { 0, 0 }, /* PE exe range set with WINEPRELOADRESERVE */
116 { 0, 0 } /* end of list */
117 };
118
119 /* debugging */
120 #undef DUMP_SEGMENTS
121 #undef DUMP_AUX_INFO
122 #undef DUMP_SYMS
123
124 /* older systems may not define these */
125 #ifndef PT_TLS
126 #define PT_TLS 7
127 #endif
128
129 #ifndef AT_SYSINFO
130 #define AT_SYSINFO 32
131 #endif
132 #ifndef AT_SYSINFO_EHDR
133 #define AT_SYSINFO_EHDR 33
134 #endif
135
136 #ifndef DT_GNU_HASH
137 #define DT_GNU_HASH 0x6ffffef5
138 #endif
139
140 static unsigned int page_size, page_mask;
141 static char *preloader_start, *preloader_end;
142
143 struct wld_link_map {
144 ElfW(Addr) l_addr;
145 ElfW(Dyn) *l_ld;
146 ElfW(Phdr)*l_phdr;
147 ElfW(Addr) l_entry;
148 ElfW(Half) l_ldnum;
149 ElfW(Half) l_phnum;
150 ElfW(Addr) l_map_start, l_map_end;
151 ElfW(Addr) l_interp;
152 };
153
154
155 /*
156 * The __bb_init_func is an empty function only called when file is
157 * compiled with gcc flags "-fprofile-arcs -ftest-coverage". This
158 * function is normally provided by libc's startup files, but since we
159 * build the preloader with "-nostartfiles -nodefaultlibs", we have to
160 * provide our own (empty) version, otherwise linker fails.
161 */
162 void __bb_init_func(void) { return; }
163
164 /* similar to the above but for -fstack-protector */
165 void *__stack_chk_guard = 0;
166 void __stack_chk_fail(void) { return; }
167
168 /* data for setting up the glibc-style thread-local storage in %gs */
169
170 static int thread_data[256];
171
172 struct
173 {
174 /* this is the kernel modify_ldt struct */
175 unsigned int entry_number;
176 unsigned long base_addr;
177 unsigned int limit;
178 unsigned int seg_32bit : 1;
179 unsigned int contents : 2;
180 unsigned int read_exec_only : 1;
181 unsigned int limit_in_pages : 1;
182 unsigned int seg_not_present : 1;
183 unsigned int usable : 1;
184 unsigned int garbage : 25;
185 } thread_ldt = { -1, (unsigned long)thread_data, 0xfffff, 1, 0, 0, 1, 0, 1, 0 };
186
187
188 /*
189 * The _start function is the entry and exit point of this program
190 *
191 * It calls wld_start, passing a pointer to the args it receives
192 * then jumps to the address wld_start returns.
193 */
194 void _start();
195 extern char _end[];
196 __ASM_GLOBAL_FUNC(_start,
197 "\tmovl $243,%eax\n" /* SYS_set_thread_area */
198 "\tmovl $thread_ldt,%ebx\n"
199 "\tint $0x80\n" /* allocate gs segment */
200 "\torl %eax,%eax\n"
201 "\tjl 1f\n"
202 "\tmovl thread_ldt,%eax\n" /* thread_ldt.entry_number */
203 "\tshl $3,%eax\n"
204 "\torl $3,%eax\n"
205 "\tmov %ax,%gs\n"
206 "\tmov %ax,%fs\n" /* set %fs too so libwine can retrieve it later on */
207 "1:\tmovl %esp,%eax\n"
208 "\tleal -136(%esp),%esp\n" /* allocate some space for extra aux values */
209 "\tpushl %eax\n" /* orig stack pointer */
210 "\tpushl %esp\n" /* ptr to orig stack pointer */
211 "\tcall wld_start\n"
212 "\tpopl %ecx\n" /* remove ptr to stack pointer */
213 "\tpopl %esp\n" /* new stack pointer */
214 "\tpush %eax\n" /* ELF interpreter entry point */
215 "\txor %eax,%eax\n"
216 "\txor %ecx,%ecx\n"
217 "\txor %edx,%edx\n"
218 "\tmov %ax,%gs\n" /* clear %gs again */
219 "\tret\n")
220
221 /* wrappers for Linux system calls */
222
223 #define SYSCALL_RET(ret) (((ret) < 0 && (ret) > -4096) ? -1 : (ret))
224
225 static inline __attribute__((noreturn)) void wld_exit( int code )
226 {
227 for (;;) /* avoid warning */
228 __asm__ __volatile__( "pushl %%ebx; movl %1,%%ebx; int $0x80; popl %%ebx"
229 : : "a" (SYS_exit), "r" (code) );
230 }
231
232 static inline int wld_open( const char *name, int flags )
233 {
234 int ret;
235 __asm__ __volatile__( "pushl %%ebx; movl %2,%%ebx; int $0x80; popl %%ebx"
236 : "=a" (ret) : "" (SYS_open), "r" (name), "c" (flags) );
237 return SYSCALL_RET(ret);
238 }
239
240 static inline int wld_close( int fd )
241 {
242 int ret;
243 __asm__ __volatile__( "pushl %%ebx; movl %2,%%ebx; int $0x80; popl %%ebx"
244 : "=a" (ret) : "" (SYS_close), "r" (fd) );
245 return SYSCALL_RET(ret);
246 }
247
248 static inline ssize_t wld_read( int fd, void *buffer, size_t len )
249 {
250 int ret;
251 __asm__ __volatile__( "pushl %%ebx; movl %2,%%ebx; int $0x80; popl %%ebx"
252 : "=a" (ret)
253 : "" (SYS_read), "r" (fd), "c" (buffer), "d" (len)
254 : "memory" );
255 return SYSCALL_RET(ret);
256 }
257
258 static inline ssize_t wld_write( int fd, const void *buffer, size_t len )
259 {
260 int ret;
261 __asm__ __volatile__( "pushl %%ebx; movl %2,%%ebx; int $0x80; popl %%ebx"
262 : "=a" (ret) : "" (SYS_write), "r" (fd), "c" (buffer), "d" (len) );
263 return SYSCALL_RET(ret);
264 }
265
266 static inline int wld_mprotect( const void *addr, size_t len, int prot )
267 {
268 int ret;
269 __asm__ __volatile__( "pushl %%ebx; movl %2,%%ebx; int $0x80; popl %%ebx"
270 : "=a" (ret) : "" (SYS_mprotect), "r" (addr), "c" (len), "d" (prot) );
271 return SYSCALL_RET(ret);
272 }
273
274 static void *wld_mmap( void *start, size_t len, int prot, int flags, int fd, off_t offset )
275 {
276 int ret;
277
278 struct
279 {
280 void *addr;
281 unsigned int length;
282 unsigned int prot;
283 unsigned int flags;
284 unsigned int fd;
285 unsigned int offset;
286 } args;
287
288 args.addr = start;
289 args.length = len;
290 args.prot = prot;
291 args.flags = flags;
292 args.fd = fd;
293 args.offset = offset;
294 __asm__ __volatile__( "pushl %%ebx; movl %2,%%ebx; int $0x80; popl %%ebx"
295 : "=a" (ret) : "" (SYS_mmap), "q" (&args) : "memory" );
296 return (void *)SYSCALL_RET(ret);
297 }
298
299 static inline uid_t wld_getuid(void)
300 {
301 uid_t ret;
302 __asm__( "int $0x80" : "=a" (ret) : "" (SYS_getuid) );
303 return ret;
304 }
305
306 static inline uid_t wld_geteuid(void)
307 {
308 uid_t ret;
309 __asm__( "int $0x80" : "=a" (ret) : "" (SYS_geteuid) );
310 return ret;
311 }
312
313 static inline gid_t wld_getgid(void)
314 {
315 gid_t ret;
316 __asm__( "int $0x80" : "=a" (ret) : "" (SYS_getgid) );
317 return ret;
318 }
319
320 static inline gid_t wld_getegid(void)
321 {
322 gid_t ret;
323 __asm__( "int $0x80" : "=a" (ret) : "" (SYS_getegid) );
324 return ret;
325 }
326
327 static inline int wld_prctl( int code, int arg )
328 {
329 int ret;
330 __asm__ __volatile__( "pushl %%ebx; movl %2,%%ebx; int $0x80; popl %%ebx"
331 : "=a" (ret) : "" (SYS_prctl), "r" (code), "c" (arg) );
332 return SYSCALL_RET(ret);
333 }
334
335
336 /* replacement for libc functions */
337
338 static int wld_strcmp( const char *str1, const char *str2 )
339 {
340 while (*str1 && (*str1 == *str2)) { str1++; str2++; }
341 return *str1 - *str2;
342 }
343
344 static int wld_strncmp( const char *str1, const char *str2, size_t len )
345 {
346 if (len <= 0) return 0;
347 while ((--len > 0) && *str1 && (*str1 == *str2)) { str1++; str2++; }
348 return *str1 - *str2;
349 }
350
351 static inline void *wld_memset( void *dest, int val, size_t len )
352 {
353 char *dst = dest;
354 while (len--) *dst++ = val;
355 return dest;
356 }
357
358 /*
359 * wld_printf - just the basics
360 *
361 * %x prints a hex number
362 * %s prints a string
363 * %p prints a pointer
364 */
365 static int wld_vsprintf(char *buffer, const char *fmt, va_list args )
366 {
367 static const char hex_chars[16] = "0123456789abcdef";
368 const char *p = fmt;
369 char *str = buffer;
370 int i;
371
372 while( *p )
373 {
374 if( *p == '%' )
375 {
376 p++;
377 if( *p == 'x' )
378 {
379 unsigned int x = va_arg( args, unsigned int );
380 for(i=7; i>=0; i--)
381 *str++ = hex_chars[(x>>(i*4))&0xf];
382 }
383 else if (p[0] == 'l' && p[1] == 'x')
384 {
385 unsigned long x = va_arg( args, unsigned long );
386 for(i=7; i>=0; i--)
387 *str++ = hex_chars[(x>>(i*4))&0xf];
388 p++;
389 }
390 else if( *p == 'p' )
391 {
392 unsigned long x = (unsigned long)va_arg( args, void * );
393 for(i=7; i>=0; i--)
394 *str++ = hex_chars[(x>>(i*4))&0xf];
395 }
396 else if( *p == 's' )
397 {
398 char *s = va_arg( args, char * );
399 while(*s)
400 *str++ = *s++;
401 }
402 else if( *p == 0 )
403 break;
404 p++;
405 }
406 *str++ = *p++;
407 }
408 *str = 0;
409 return str - buffer;
410 }
411
412 static __attribute__((format(printf,1,2))) void wld_printf(const char *fmt, ... )
413 {
414 va_list args;
415 char buffer[256];
416 int len;
417
418 va_start( args, fmt );
419 len = wld_vsprintf(buffer, fmt, args );
420 va_end( args );
421 wld_write(2, buffer, len);
422 }
423
424 static __attribute__((noreturn,format(printf,1,2))) void fatal_error(const char *fmt, ... )
425 {
426 va_list args;
427 char buffer[256];
428 int len;
429
430 va_start( args, fmt );
431 len = wld_vsprintf(buffer, fmt, args );
432 va_end( args );
433 wld_write(2, buffer, len);
434 wld_exit(1);
435 }
436
437 #ifdef DUMP_AUX_INFO
438 /*
439 * Dump interesting bits of the ELF auxv_t structure that is passed
440 * as the 4th parameter to the _start function
441 */
442 static void dump_auxiliary( ElfW(auxv_t) *av )
443 {
444 #define NAME(at) { at, #at }
445 static const struct { int val; const char *name; } names[] =
446 {
447 NAME(AT_BASE),
448 NAME(AT_CLKTCK),
449 NAME(AT_EGID),
450 NAME(AT_ENTRY),
451 NAME(AT_EUID),
452 NAME(AT_FLAGS),
453 NAME(AT_GID),
454 NAME(AT_HWCAP),
455 NAME(AT_PAGESZ),
456 NAME(AT_PHDR),
457 NAME(AT_PHENT),
458 NAME(AT_PHNUM),
459 NAME(AT_PLATFORM),
460 NAME(AT_SYSINFO),
461 NAME(AT_SYSINFO_EHDR),
462 NAME(AT_UID),
463 { 0, NULL }
464 };
465 #undef NAME
466
467 int i;
468
469 for ( ; av->a_type != AT_NULL; av++)
470 {
471 for (i = 0; names[i].name; i++) if (names[i].val == av->a_type) break;
472 if (names[i].name) wld_printf("%s = %lx\n", names[i].name, av->a_un.a_val);
473 else wld_printf( "%x = %lx\n", av->a_type, av->a_un.a_val );
474 }
475 }
476 #endif
477
478 /*
479 * set_auxiliary_values
480 *
481 * Set the new auxiliary values
482 */
483 static void set_auxiliary_values( ElfW(auxv_t) *av, const ElfW(auxv_t) *new_av,
484 const ElfW(auxv_t) *delete_av, void **stack )
485 {
486 int i, j, av_count = 0, new_count = 0, delete_count = 0;
487 char *src, *dst;
488
489 /* count how many aux values we have already */
490 while (av[av_count].a_type != AT_NULL) av_count++;
491
492 /* delete unwanted values */
493 for (j = 0; delete_av[j].a_type != AT_NULL; j++)
494 {
495 for (i = 0; i < av_count; i++) if (av[i].a_type == delete_av[j].a_type)
496 {
497 av[i].a_type = av[av_count-1].a_type;
498 av[i].a_un.a_val = av[av_count-1].a_un.a_val;
499 av[--av_count].a_type = AT_NULL;
500 delete_count++;
501 break;
502 }
503 }
504
505 /* count how many values we have in new_av that aren't in av */
506 for (j = 0; new_av[j].a_type != AT_NULL; j++)
507 {
508 for (i = 0; i < av_count; i++) if (av[i].a_type == new_av[j].a_type) break;
509 if (i == av_count) new_count++;
510 }
511
512 src = (char *)*stack;
513 dst = src - (new_count - delete_count) * sizeof(*av);
514 if (new_count > delete_count) /* need to make room for the extra values */
515 {
516 int len = (char *)(av + av_count + 1) - src;
517 for (i = 0; i < len; i++) dst[i] = src[i];
518 }
519 else if (new_count < delete_count) /* get rid of unused values */
520 {
521 int len = (char *)(av + av_count + 1) - dst;
522 for (i = len - 1; i >= 0; i--) dst[i] = src[i];
523 }
524 *stack = dst;
525 av -= (new_count - delete_count);
526
527 /* now set the values */
528 for (j = 0; new_av[j].a_type != AT_NULL; j++)
529 {
530 for (i = 0; i < av_count; i++) if (av[i].a_type == new_av[j].a_type) break;
531 if (i < av_count) av[i].a_un.a_val = new_av[j].a_un.a_val;
532 else
533 {
534 av[av_count].a_type = new_av[j].a_type;
535 av[av_count].a_un.a_val = new_av[j].a_un.a_val;
536 av_count++;
537 }
538 }
539
540 #ifdef DUMP_AUX_INFO
541 wld_printf("New auxiliary info:\n");
542 dump_auxiliary( av );
543 #endif
544 }
545
546 /*
547 * get_auxiliary
548 *
549 * Get a field of the auxiliary structure
550 */
551 static int get_auxiliary( ElfW(auxv_t) *av, int type, int def_val )
552 {
553 for ( ; av->a_type != AT_NULL; av++)
554 if( av->a_type == type ) return av->a_un.a_val;
555 return def_val;
556 }
557
558 /*
559 * map_so_lib
560 *
561 * modelled after _dl_map_object_from_fd() from glibc-2.3.1/elf/dl-load.c
562 *
563 * This function maps the segments from an ELF object, and optionally
564 * stores information about the mapping into the auxv_t structure.
565 */
566 static void map_so_lib( const char *name, struct wld_link_map *l)
567 {
568 int fd;
569 unsigned char buf[0x800];
570 ElfW(Ehdr) *header = (ElfW(Ehdr)*)buf;
571 ElfW(Phdr) *phdr, *ph;
572 /* Scan the program header table, collecting its load commands. */
573 struct loadcmd
574 {
575 ElfW(Addr) mapstart, mapend, dataend, allocend;
576 off_t mapoff;
577 int prot;
578 } loadcmds[16], *c;
579 size_t nloadcmds = 0, maplength;
580
581 fd = wld_open( name, O_RDONLY );
582 if (fd == -1) fatal_error("%s: could not open\n", name );
583
584 if (wld_read( fd, buf, sizeof(buf) ) != sizeof(buf))
585 fatal_error("%s: failed to read ELF header\n", name);
586
587 phdr = (void*) (((unsigned char*)buf) + header->e_phoff);
588
589 if( ( header->e_ident[0] != 0x7f ) ||
590 ( header->e_ident[1] != 'E' ) ||
591 ( header->e_ident[2] != 'L' ) ||
592 ( header->e_ident[3] != 'F' ) )
593 fatal_error( "%s: not an ELF binary... don't know how to load it\n", name );
594
595 if( header->e_machine != EM_386 )
596 fatal_error("%s: not an i386 ELF binary... don't know how to load it\n", name );
597
598 if (header->e_phnum > sizeof(loadcmds)/sizeof(loadcmds[0]))
599 fatal_error( "%s: oops... not enough space for load commands\n", name );
600
601 maplength = header->e_phnum * sizeof (ElfW(Phdr));
602 if (header->e_phoff + maplength > sizeof(buf))
603 fatal_error( "%s: oops... not enough space for ELF headers\n", name );
604
605 l->l_ld = 0;
606 l->l_addr = 0;
607 l->l_phdr = 0;
608 l->l_phnum = header->e_phnum;
609 l->l_entry = header->e_entry;
610 l->l_interp = 0;
611
612 for (ph = phdr; ph < &phdr[l->l_phnum]; ++ph)
613 {
614
615 #ifdef DUMP_SEGMENTS
616 wld_printf( "ph = %p\n", ph );
617 wld_printf( " p_type = %x\n", ph->p_type );
618 wld_printf( " p_flags = %x\n", ph->p_flags );
619 wld_printf( " p_offset = %x\n", ph->p_offset );
620 wld_printf( " p_vaddr = %x\n", ph->p_vaddr );
621 wld_printf( " p_paddr = %x\n", ph->p_paddr );
622 wld_printf( " p_filesz = %x\n", ph->p_filesz );
623 wld_printf( " p_memsz = %x\n", ph->p_memsz );
624 wld_printf( " p_align = %x\n", ph->p_align );
625 #endif
626
627 switch (ph->p_type)
628 {
629 /* These entries tell us where to find things once the file's
630 segments are mapped in. We record the addresses it says
631 verbatim, and later correct for the run-time load address. */
632 case PT_DYNAMIC:
633 l->l_ld = (void *) ph->p_vaddr;
634 l->l_ldnum = ph->p_memsz / sizeof (Elf32_Dyn);
635 break;
636
637 case PT_PHDR:
638 l->l_phdr = (void *) ph->p_vaddr;
639 break;
640
641 case PT_LOAD:
642 {
643 if ((ph->p_align & page_mask) != 0)
644 fatal_error( "%s: ELF load command alignment not page-aligned\n", name );
645
646 if (((ph->p_vaddr - ph->p_offset) & (ph->p_align - 1)) != 0)
647 fatal_error( "%s: ELF load command address/offset not properly aligned\n", name );
648
649 c = &loadcmds[nloadcmds++];
650 c->mapstart = ph->p_vaddr & ~(ph->p_align - 1);
651 c->mapend = ((ph->p_vaddr + ph->p_filesz + page_mask) & ~page_mask);
652 c->dataend = ph->p_vaddr + ph->p_filesz;
653 c->allocend = ph->p_vaddr + ph->p_memsz;
654 c->mapoff = ph->p_offset & ~(ph->p_align - 1);
655
656 c->prot = 0;
657 if (ph->p_flags & PF_R)
658 c->prot |= PROT_READ;
659 if (ph->p_flags & PF_W)
660 c->prot |= PROT_WRITE;
661 if (ph->p_flags & PF_X)
662 c->prot |= PROT_EXEC;
663 }
664 break;
665
666 case PT_INTERP:
667 l->l_interp = ph->p_vaddr;
668 break;
669
670 case PT_TLS:
671 /*
672 * We don't need to set anything up because we're
673 * emulating the kernel, not ld-linux.so.2
674 * The ELF loader will set up the TLS data itself.
675 */
676 case PT_SHLIB:
677 case PT_NOTE:
678 default:
679 break;
680 }
681 }
682
683 /* Now process the load commands and map segments into memory. */
684 c = loadcmds;
685
686 /* Length of the sections to be loaded. */
687 maplength = loadcmds[nloadcmds - 1].allocend - c->mapstart;
688
689 if( header->e_type == ET_DYN )
690 {
691 ElfW(Addr) mappref;
692 mappref = (ELF_PREFERRED_ADDRESS (loader, maplength, c->mapstart)
693 - MAP_BASE_ADDR (l));
694
695 /* Remember which part of the address space this object uses. */
696 l->l_map_start = (ElfW(Addr)) wld_mmap ((void *) mappref, maplength,
697 c->prot, MAP_COPY | MAP_FILE,
698 fd, c->mapoff);
699 /* wld_printf("set : offset = %x\n", c->mapoff); */
700 /* wld_printf("l->l_map_start = %x\n", l->l_map_start); */
701
702 l->l_map_end = l->l_map_start + maplength;
703 l->l_addr = l->l_map_start - c->mapstart;
704
705 wld_mprotect ((caddr_t) (l->l_addr + c->mapend),
706 loadcmds[nloadcmds - 1].allocend - c->mapend,
707 PROT_NONE);
708 goto postmap;
709 }
710 else
711 {
712 /* sanity check */
713 if ((char *)c->mapstart + maplength > preloader_start &&
714 (char *)c->mapstart <= preloader_end)
715 fatal_error( "%s: binary overlaps preloader (%p-%p)\n",
716 name, (char *)c->mapstart, (char *)c->mapstart + maplength );
717
718 ELF_FIXED_ADDRESS (loader, c->mapstart);
719 }
720
721 /* Remember which part of the address space this object uses. */
722 l->l_map_start = c->mapstart + l->l_addr;
723 l->l_map_end = l->l_map_start + maplength;
724
725 while (c < &loadcmds[nloadcmds])
726 {
727 if (c->mapend > c->mapstart)
728 /* Map the segment contents from the file. */
729 wld_mmap ((void *) (l->l_addr + c->mapstart),
730 c->mapend - c->mapstart, c->prot,
731 MAP_FIXED | MAP_COPY | MAP_FILE, fd, c->mapoff);
732
733 postmap:
734 if (l->l_phdr == 0
735 && (ElfW(Off)) c->mapoff <= header->e_phoff
736 && ((size_t) (c->mapend - c->mapstart + c->mapoff)
737 >= header->e_phoff + header->e_phnum * sizeof (ElfW(Phdr))))
738 /* Found the program header in this segment. */
739 l->l_phdr = (void *)(unsigned int) (c->mapstart + header->e_phoff - c->mapoff);
740
741 if (c->allocend > c->dataend)
742 {
743 /* Extra zero pages should appear at the end of this segment,
744 after the data mapped from the file. */
745 ElfW(Addr) zero, zeroend, zeropage;
746
747 zero = l->l_addr + c->dataend;
748 zeroend = l->l_addr + c->allocend;
749 zeropage = (zero + page_mask) & ~page_mask;
750
751 /*
752 * This is different from the dl-load load...
753 * ld-linux.so.2 relies on the whole page being zero'ed
754 */
755 zeroend = (zeroend + page_mask) & ~page_mask;
756
757 if (zeroend < zeropage)
758 {
759 /* All the extra data is in the last page of the segment.
760 We can just zero it. */
761 zeropage = zeroend;
762 }
763
764 if (zeropage > zero)
765 {
766 /* Zero the final part of the last page of the segment. */
767 if ((c->prot & PROT_WRITE) == 0)
768 {
769 /* Dag nab it. */
770 wld_mprotect ((caddr_t) (zero & ~page_mask), page_size, c->prot|PROT_WRITE);
771 }
772 wld_memset ((void *) zero, '\0', zeropage - zero);
773 if ((c->prot & PROT_WRITE) == 0)
774 wld_mprotect ((caddr_t) (zero & ~page_mask), page_size, c->prot);
775 }
776
777 if (zeroend > zeropage)
778 {
779 /* Map the remaining zero pages in from the zero fill FD. */
780 caddr_t mapat;
781 mapat = wld_mmap ((caddr_t) zeropage, zeroend - zeropage,
782 c->prot, MAP_ANON|MAP_PRIVATE|MAP_FIXED,
783 -1, 0);
784 }
785 }
786
787 ++c;
788 }
789
790 if (l->l_phdr == NULL) fatal_error("no program header\n");
791
792 l->l_phdr = (void *)((ElfW(Addr))l->l_phdr + l->l_addr);
793 l->l_entry += l->l_addr;
794
795 wld_close( fd );
796 }
797
798
799 static unsigned int elf_hash( const char *name )
800 {
801 unsigned int hi, hash = 0;
802 while (*name)
803 {
804 hash = (hash << 4) + (unsigned char)*name++;
805 hi = hash & 0xf0000000;
806 hash ^= hi;
807 hash ^= hi >> 24;
808 }
809 return hash;
810 }
811
812 static unsigned int gnu_hash( const char *name )
813 {
814 unsigned int h = 5381;
815 while (*name) h = h * 33 + (unsigned char)*name++;
816 return h;
817 }
818
819 /*
820 * Find a symbol in the symbol table of the executable loaded
821 */
822 static void *find_symbol( const ElfW(Phdr) *phdr, int num, const char *var, int type )
823 {
824 const ElfW(Dyn) *dyn = NULL;
825 const ElfW(Phdr) *ph;
826 const ElfW(Sym) *symtab = NULL;
827 const Elf_Symndx *hashtab = NULL;
828 const Elf32_Word *gnu_hashtab = NULL;
829 const char *strings = NULL;
830 Elf_Symndx idx;
831
832 /* check the values */
833 #ifdef DUMP_SYMS
834 wld_printf("%p %x\n", phdr, num );
835 #endif
836 if( ( phdr == NULL ) || ( num == 0 ) )
837 {
838 wld_printf("could not find PT_DYNAMIC header entry\n");
839 return NULL;
840 }
841
842 /* parse the (already loaded) ELF executable's header */
843 for (ph = phdr; ph < &phdr[num]; ++ph)
844 {
845 if( PT_DYNAMIC == ph->p_type )
846 {
847 dyn = (void *) ph->p_vaddr;
848 num = ph->p_memsz / sizeof (Elf32_Dyn);
849 break;
850 }
851 }
852 if( !dyn ) return NULL;
853
854 while( dyn->d_tag )
855 {
856 if( dyn->d_tag == DT_STRTAB )
857 strings = (const char*) dyn->d_un.d_ptr;
858 if( dyn->d_tag == DT_SYMTAB )
859 symtab = (const ElfW(Sym) *)dyn->d_un.d_ptr;
860 if( dyn->d_tag == DT_HASH )
861 hashtab = (const Elf_Symndx *)dyn->d_un.d_ptr;
862 if( dyn->d_tag == DT_GNU_HASH )
863 gnu_hashtab = (const Elf32_Word *)dyn->d_un.d_ptr;
864 #ifdef DUMP_SYMS
865 wld_printf("%x %x\n", dyn->d_tag, dyn->d_un.d_ptr );
866 #endif
867 dyn++;
868 }
869
870 if( (!symtab) || (!strings) ) return NULL;
871
872 if (gnu_hashtab) /* new style hash table */
873 {
874 const unsigned int hash = gnu_hash(var);
875 const Elf32_Word nbuckets = gnu_hashtab[0];
876 const Elf32_Word symbias = gnu_hashtab[1];
877 const Elf32_Word nwords = gnu_hashtab[2];
878 const ElfW(Addr) *bitmask = (const ElfW(Addr) *)(gnu_hashtab + 4);
879 const Elf32_Word *buckets = (const Elf32_Word *)(bitmask + nwords);
880 const Elf32_Word *chains = buckets + nbuckets - symbias;
881
882 if (!(idx = buckets[hash % nbuckets])) return NULL;
883 do
884 {
885 if ((chains[idx] & ~1u) == (hash & ~1u) &&
886 symtab[idx].st_info == ELF32_ST_INFO( STB_GLOBAL, type ) &&
887 !wld_strcmp( strings + symtab[idx].st_name, var ))
888 goto found;
889 } while (!(chains[idx++] & 1u));
890 }
891 else if (hashtab) /* old style hash table */
892 {
893 const unsigned int hash = elf_hash(var);
894 const Elf_Symndx nbuckets = hashtab[0];
895 const Elf_Symndx *buckets = hashtab + 2;
896 const Elf_Symndx *chains = buckets + nbuckets;
897
898 for (idx = buckets[hash % nbuckets]; idx != STN_UNDEF; idx = chains[idx])
899 {
900 if (symtab[idx].st_info == ELF32_ST_INFO( STB_GLOBAL, type ) &&
901 !wld_strcmp( strings + symtab[idx].st_name, var ))
902 goto found;
903 }
904 }
905 return NULL;
906
907 found:
908 #ifdef DUMP_SYMS
909 wld_printf("Found %s -> %x\n", strings + symtab[idx].st_name, symtab[idx].st_value );
910 #endif
911 return (void *)symtab[idx].st_value;
912 }
913
914 /*
915 * preload_reserve
916 *
917 * Reserve a range specified in string format
918 */
919 static void preload_reserve( const char *str )
920 {
921 const char *p;
922 unsigned long result = 0;
923 void *start = NULL, *end = NULL;
924 int i, first = 1;
925
926 for (p = str; *p; p++)
927 {
928 if (*p >= '' && *p <= '9') result = result * 16 + *p - '';
929 else if (*p >= 'a' && *p <= 'f') result = result * 16 + *p - 'a' + 10;
930 else if (*p >= 'A' && *p <= 'F') result = result * 16 + *p - 'A' + 10;
931 else if (*p == '-')
932 {
933 if (!first) goto error;
934 start = (void *)(result & ~page_mask);
935 result = 0;
936 first = 0;
937 }
938 else goto error;
939 }
940 if (!first) end = (void *)((result + page_mask) & ~page_mask);
941 else if (result) goto error; /* single value '' is allowed */
942
943 /* sanity checks */
944 if (end <= start) start = end = NULL;
945 else if ((char *)end > preloader_start &&
946 (char *)start <= preloader_end)
947 {
948 wld_printf( "WINEPRELOADRESERVE range %p-%p overlaps preloader %p-%p\n",
949 start, end, preloader_start, preloader_end );
950 start = end = NULL;
951 }
952
953 /* check for overlap with low memory areas */
954 for (i = 0; preload_info[i].size; i++)
955 {
956 if ((char *)preload_info[i].addr > (char *)0x00110000) break;
957 if ((char *)end <= (char *)preload_info[i].addr + preload_info[i].size)
958 {
959 start = end = NULL;
960 break;
961 }
962 if ((char *)start < (char *)preload_info[i].addr + preload_info[i].size)
963 start = (char *)preload_info[i].addr + preload_info[i].size;
964 }
965
966 while (preload_info[i].size) i++;
967 preload_info[i].addr = start;
968 preload_info[i].size = (char *)end - (char *)start;
969 return;
970
971 error:
972 fatal_error( "invalid WINEPRELOADRESERVE value '%s'\n", str );
973 }
974
975 /* check if address is in one of the reserved ranges */
976 static int is_addr_reserved( const void *addr )
977 {
978 int i;
979
980 for (i = 0; preload_info[i].size; i++)
981 {
982 if ((const char *)addr >= (const char *)preload_info[i].addr &&
983 (const char *)addr < (const char *)preload_info[i].addr + preload_info[i].size)
984 return 1;
985 }
986 return 0;
987 }
988
989 /* remove a range from the preload list */
990 static void remove_preload_range( int i )
991 {
992 while (preload_info[i].size)
993 {
994 preload_info[i].addr = preload_info[i+1].addr;
995 preload_info[i].size = preload_info[i+1].size;
996 i++;
997 }
998 }
999
1000 /*
1001 * is_in_preload_range
1002 *
1003 * Check if address of the given aux value is in one of the reserved ranges
1004 */
1005 static int is_in_preload_range( const ElfW(auxv_t) *av, int type )
1006 {
1007 while (av->a_type != AT_NULL)
1008 {
1009 if (av->a_type == type) return is_addr_reserved( (const void *)av->a_un.a_val );
1010 av++;
1011 }
1012 return 0;
1013 }
1014
1015 /* set the process name if supported */
1016 static void set_process_name( int argc, char *argv[] )
1017 {
1018 int i;
1019 unsigned int off;
1020 char *p, *name, *end;
1021
1022 /* set the process short name */
1023 for (p = name = argv[1]; *p; p++) if (p[0] == '/' && p[1]) name = p + 1;
1024 if (wld_prctl( 15 /* PR_SET_NAME */, (int)name ) == -1) return;
1025
1026 /* find the end of the argv array and move everything down */
1027 end = argv[argc - 1];
1028 while (*end) end++;
1029 off = argv[1] - argv[0];
1030 for (p = argv[1]; p <= end; p++) *(p - off) = *p;
1031 wld_memset( end - off, 0, off );
1032 for (i = 1; i < argc; i++) argv[i] -= off;
1033 }
1034
1035
1036 /*
1037 * wld_start
1038 *
1039 * Repeat the actions the kernel would do when loading a dynamically linked .so
1040 * Load the binary and then its ELF interpreter.
1041 * Note, we assume that the binary is a dynamically linked ELF shared object.
1042 */
1043 void* wld_start( void **stack )
1044 {
1045 int i, *pargc;
1046 char **argv, **p;