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[apple/xnu.git] / bsd / kern / mach_loader.c
1 /*
2 * Copyright (c) 2000-2010 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28 /*
29 * Copyright (C) 1988, 1989, NeXT, Inc.
30 *
31 * File: kern/mach_loader.c
32 * Author: Avadis Tevanian, Jr.
33 *
34 * Mach object file loader (kernel version, for now).
35 *
36 * 21-Jul-88 Avadis Tevanian, Jr. (avie) at NeXT
37 * Started.
38 */
39
40 #include <sys/param.h>
41 #include <sys/vnode_internal.h>
42 #include <sys/uio.h>
43 #include <sys/namei.h>
44 #include <sys/proc_internal.h>
45 #include <sys/kauth.h>
46 #include <sys/stat.h>
47 #include <sys/malloc.h>
48 #include <sys/mount_internal.h>
49 #include <sys/fcntl.h>
50 #include <sys/ubc_internal.h>
51 #include <sys/imgact.h>
52
53 #include <mach/mach_types.h>
54 #include <mach/vm_map.h> /* vm_allocate() */
55 #include <mach/mach_vm.h> /* mach_vm_allocate() */
56 #include <mach/vm_statistics.h>
57 #include <mach/task.h>
58 #include <mach/thread_act.h>
59
60 #include <machine/vmparam.h>
61 #include <machine/exec.h>
62 #include <machine/pal_routines.h>
63
64 #include <kern/kern_types.h>
65 #include <kern/cpu_number.h>
66 #include <kern/mach_loader.h>
67 #include <kern/mach_fat.h>
68 #include <kern/kalloc.h>
69 #include <kern/task.h>
70 #include <kern/thread.h>
71 #include <kern/page_decrypt.h>
72
73 #include <mach-o/fat.h>
74 #include <mach-o/loader.h>
75
76 #include <vm/pmap.h>
77 #include <vm/vm_map.h>
78 #include <vm/vm_kern.h>
79 #include <vm/vm_pager.h>
80 #include <vm/vnode_pager.h>
81 #include <vm/vm_protos.h>
82
83 /*
84 * XXX vm/pmap.h should not treat these prototypes as MACH_KERNEL_PRIVATE
85 * when KERNEL is defined.
86 */
87 extern pmap_t pmap_create(vm_map_size_t size, boolean_t is_64bit);
88 extern void pmap_switch(pmap_t);
89
90 /*
91 * XXX kern/thread.h should not treat these prototypes as MACH_KERNEL_PRIVATE
92 * when KERNEL is defined.
93 */
94 extern kern_return_t thread_setstatus(thread_t thread, int flavor,
95 thread_state_t tstate,
96 mach_msg_type_number_t count);
97
98 extern kern_return_t thread_state_initialize(thread_t thread);
99
100
101 /* XXX should have prototypes in a shared header file */
102 extern int get_map_nentries(vm_map_t);
103
104 extern kern_return_t memory_object_signed(memory_object_control_t control,
105 boolean_t is_signed);
106
107 /* An empty load_result_t */
108 static load_result_t load_result_null = {
109 .mach_header = MACH_VM_MIN_ADDRESS,
110 .entry_point = MACH_VM_MIN_ADDRESS,
111 .user_stack = MACH_VM_MIN_ADDRESS,
112 .all_image_info_addr = MACH_VM_MIN_ADDRESS,
113 .all_image_info_size = 0,
114 .thread_count = 0,
115 .unixproc = 0,
116 .dynlinker = 0,
117 .customstack = 0,
118 .validentry = 0,
119 .csflags = 0,
120 .uuid = { 0 },
121 .min_vm_addr = MACH_VM_MAX_ADDRESS,
122 .max_vm_addr = MACH_VM_MIN_ADDRESS
123 };
124
125 /*
126 * Prototypes of static functions.
127 */
128 static load_return_t
129 parse_machfile(
130 struct vnode *vp,
131 vm_map_t map,
132 thread_t thread,
133 struct mach_header *header,
134 off_t file_offset,
135 off_t macho_size,
136 int depth,
137 int64_t slide,
138 load_result_t *result
139 );
140
141 static load_return_t
142 load_segment(
143 struct load_command *lcp,
144 uint32_t filetype,
145 void *control,
146 off_t pager_offset,
147 off_t macho_size,
148 struct vnode *vp,
149 vm_map_t map,
150 int64_t slide,
151 load_result_t *result
152 );
153
154 static load_return_t
155 load_code_signature(
156 struct linkedit_data_command *lcp,
157 struct vnode *vp,
158 off_t macho_offset,
159 off_t macho_size,
160 cpu_type_t cputype,
161 load_result_t *result);
162
163 #if CONFIG_CODE_DECRYPTION
164 static load_return_t
165 set_code_unprotect(
166 struct encryption_info_command *lcp,
167 caddr_t addr,
168 vm_map_t map,
169 struct vnode *vp);
170 #endif
171
172 static load_return_t
173 load_unixthread(
174 struct thread_command *tcp,
175 thread_t thread,
176 int64_t slide,
177 load_result_t *result
178 );
179
180 static load_return_t
181 load_threadstate(
182 thread_t thread,
183 uint32_t *ts,
184 uint32_t total_size
185 );
186
187 static load_return_t
188 load_threadstack(
189 thread_t thread,
190 uint32_t *ts,
191 uint32_t total_size,
192 mach_vm_offset_t *user_stack,
193 int *customstack
194 );
195
196 static load_return_t
197 load_threadentry(
198 thread_t thread,
199 uint32_t *ts,
200 uint32_t total_size,
201 mach_vm_offset_t *entry_point
202 );
203
204 static load_return_t
205 load_dylinker(
206 struct dylinker_command *lcp,
207 integer_t archbits,
208 vm_map_t map,
209 thread_t thread,
210 int depth,
211 int64_t slide,
212 load_result_t *result
213 );
214
215 struct macho_data;
216
217 static load_return_t
218 get_macho_vnode(
219 char *path,
220 integer_t archbits,
221 struct mach_header *mach_header,
222 off_t *file_offset,
223 off_t *macho_size,
224 struct macho_data *macho_data,
225 struct vnode **vpp
226 );
227
228 static inline void
229 widen_segment_command(const struct segment_command *scp32,
230 struct segment_command_64 *scp)
231 {
232 scp->cmd = scp32->cmd;
233 scp->cmdsize = scp32->cmdsize;
234 bcopy(scp32->segname, scp->segname, sizeof(scp->segname));
235 scp->vmaddr = scp32->vmaddr;
236 scp->vmsize = scp32->vmsize;
237 scp->fileoff = scp32->fileoff;
238 scp->filesize = scp32->filesize;
239 scp->maxprot = scp32->maxprot;
240 scp->initprot = scp32->initprot;
241 scp->nsects = scp32->nsects;
242 scp->flags = scp32->flags;
243 }
244
245 static void
246 note_all_image_info_section(const struct segment_command_64 *scp,
247 boolean_t is64, size_t section_size, const void *sections,
248 int64_t slide, load_result_t *result)
249 {
250 const union {
251 struct section s32;
252 struct section_64 s64;
253 } *sectionp;
254 unsigned int i;
255
256 if (strncmp(scp->segname, "__DATA", sizeof(scp->segname)) != 0)
257 return;
258 for (i = 0; i < scp->nsects; ++i) {
259 sectionp = (const void *)
260 ((const char *)sections + section_size * i);
261 if (0 == strncmp(sectionp->s64.sectname, "__all_image_info",
262 sizeof(sectionp->s64.sectname))) {
263 result->all_image_info_addr =
264 is64 ? sectionp->s64.addr : sectionp->s32.addr;
265 result->all_image_info_addr += slide;
266 result->all_image_info_size =
267 is64 ? sectionp->s64.size : sectionp->s32.size;
268 return;
269 }
270 }
271 }
272
273 load_return_t
274 load_machfile(
275 struct image_params *imgp,
276 struct mach_header *header,
277 thread_t thread,
278 vm_map_t new_map,
279 load_result_t *result
280 )
281 {
282 struct vnode *vp = imgp->ip_vp;
283 off_t file_offset = imgp->ip_arch_offset;
284 off_t macho_size = imgp->ip_arch_size;
285
286 pmap_t pmap = 0; /* protected by create_map */
287 vm_map_t map;
288 vm_map_t old_map;
289 task_t old_task = TASK_NULL; /* protected by create_map */
290 load_result_t myresult;
291 load_return_t lret;
292 boolean_t create_map = FALSE;
293 int spawn = (imgp->ip_flags & IMGPF_SPAWN);
294 task_t task = current_task();
295 mach_vm_offset_t aslr_offset = 0;
296 kern_return_t kret;
297
298 if (new_map == VM_MAP_NULL) {
299 create_map = TRUE;
300 old_task = current_task();
301 }
302
303 /*
304 * If we are spawning, we have created backing objects for the process
305 * already, which include non-lazily creating the task map. So we
306 * are going to switch out the task map with one appropriate for the
307 * bitness of the image being loaded.
308 */
309 if (spawn) {
310 create_map = TRUE;
311 old_task = get_threadtask(thread);
312 }
313
314 if (create_map) {
315 pmap = pmap_create((vm_map_size_t) 0, (imgp->ip_flags & IMGPF_IS_64BIT));
316 pal_switch_pmap(thread, pmap, imgp->ip_flags & IMGPF_IS_64BIT);
317 map = vm_map_create(pmap,
318 0,
319 vm_compute_max_offset((imgp->ip_flags & IMGPF_IS_64BIT)),
320 TRUE);
321
322 } else
323 map = new_map;
324
325 #ifndef CONFIG_ENFORCE_SIGNED_CODE
326 /* This turns off faulting for executable pages, which allows to
327 * circumvent Code Signing Enforcement */
328 if ( (header->flags & MH_ALLOW_STACK_EXECUTION) )
329 vm_map_disable_NX(map);
330 #endif
331
332 /* Forcibly disallow execution from data pages on even if the arch
333 * normally permits it. */
334 if ((header->flags & MH_NO_HEAP_EXECUTION) && !(imgp->ip_flags & IMGPF_ALLOW_DATA_EXEC))
335 vm_map_disallow_data_exec(map);
336
337 /*
338 * Compute a random offset for ASLR.
339 */
340 if (!(imgp->ip_flags & IMGPF_DISABLE_ASLR)) {
341 aslr_offset = random();
342 aslr_offset %= 1 << ((imgp->ip_flags & IMGPF_IS_64BIT) ? 16 : 8);
343 aslr_offset <<= PAGE_SHIFT;
344 }
345
346 if (!result)
347 result = &myresult;
348
349 *result = load_result_null;
350
351 lret = parse_machfile(vp, map, thread, header, file_offset, macho_size,
352 0, (int64_t)aslr_offset, result);
353
354 if (lret != LOAD_SUCCESS) {
355 if (create_map) {
356 vm_map_deallocate(map); /* will lose pmap reference too */
357 }
358 return(lret);
359 }
360
361 /*
362 * For 64-bit users, check for presence of a 4GB page zero
363 * which will enable the kernel to share the user's address space
364 * and hence avoid TLB flushes on kernel entry/exit
365 */
366
367 if ((imgp->ip_flags & IMGPF_IS_64BIT) &&
368 vm_map_has_4GB_pagezero(map))
369 vm_map_set_4GB_pagezero(map);
370
371 /*
372 * Commit to new map.
373 *
374 * Swap the new map for the old, which consumes our new map
375 * reference but each leaves us responsible for the old_map reference.
376 * That lets us get off the pmap associated with it, and
377 * then we can release it.
378 */
379
380 if (create_map) {
381 /*
382 * If this is an exec, then we are going to destroy the old
383 * task, and it's correct to halt it; if it's spawn, the
384 * task is not yet running, and it makes no sense.
385 */
386 if (!spawn) {
387 /*
388 * Mark the task as halting and start the other
389 * threads towards terminating themselves. Then
390 * make sure any threads waiting for a process
391 * transition get informed that we are committed to
392 * this transition, and then finally complete the
393 * task halting (wait for threads and then cleanup
394 * task resources).
395 */
396 kret = task_start_halt(task);
397 if (kret != KERN_SUCCESS) {
398 return(kret);
399 }
400 proc_transcommit(current_proc(), 0);
401 task_complete_halt(task);
402 workqueue_exit(current_proc());
403 }
404 old_map = swap_task_map(old_task, thread, map, !spawn);
405 vm_map_clear_4GB_pagezero(old_map);
406 vm_map_deallocate(old_map);
407 }
408 return(LOAD_SUCCESS);
409 }
410
411 /*
412 * The file size of a mach-o file is limited to 32 bits; this is because
413 * this is the limit on the kalloc() of enough bytes for a mach_header and
414 * the contents of its sizeofcmds, which is currently constrained to 32
415 * bits in the file format itself. We read into the kernel buffer the
416 * commands section, and then parse it in order to parse the mach-o file
417 * format load_command segment(s). We are only interested in a subset of
418 * the total set of possible commands. If "map"==VM_MAP_NULL or
419 * "thread"==THREAD_NULL, do not make permament VM modifications,
420 * just preflight the parse.
421 */
422 static
423 load_return_t
424 parse_machfile(
425 struct vnode *vp,
426 vm_map_t map,
427 thread_t thread,
428 struct mach_header *header,
429 off_t file_offset,
430 off_t macho_size,
431 int depth,
432 int64_t aslr_offset,
433 load_result_t *result
434 )
435 {
436 uint32_t ncmds;
437 struct load_command *lcp;
438 struct dylinker_command *dlp = 0;
439 struct uuid_command *uulp = 0;
440 integer_t dlarchbits = 0;
441 void * control;
442 load_return_t ret = LOAD_SUCCESS;
443 caddr_t addr;
444 void * kl_addr;
445 vm_size_t size,kl_size;
446 size_t offset;
447 size_t oldoffset; /* for overflow check */
448 int pass;
449 proc_t p = current_proc(); /* XXXX */
450 int error;
451 int resid=0;
452 size_t mach_header_sz = sizeof(struct mach_header);
453 boolean_t abi64;
454 boolean_t got_code_signatures = FALSE;
455 int64_t slide = 0;
456
457 if (header->magic == MH_MAGIC_64 ||
458 header->magic == MH_CIGAM_64) {
459 mach_header_sz = sizeof(struct mach_header_64);
460 }
461
462 /*
463 * Break infinite recursion
464 */
465 if (depth > 6) {
466 return(LOAD_FAILURE);
467 }
468
469 depth++;
470
471 /*
472 * Check to see if right machine type.
473 */
474 if (((cpu_type_t)(header->cputype & ~CPU_ARCH_MASK) != cpu_type()) ||
475 !grade_binary(header->cputype,
476 header->cpusubtype & ~CPU_SUBTYPE_MASK))
477 return(LOAD_BADARCH);
478
479 abi64 = ((header->cputype & CPU_ARCH_ABI64) == CPU_ARCH_ABI64);
480
481 switch (header->filetype) {
482
483 case MH_OBJECT:
484 case MH_EXECUTE:
485 case MH_PRELOAD:
486 if (depth != 1) {
487 return (LOAD_FAILURE);
488 }
489 break;
490
491 case MH_FVMLIB:
492 case MH_DYLIB:
493 if (depth == 1) {
494 return (LOAD_FAILURE);
495 }
496 break;
497
498 case MH_DYLINKER:
499 if (depth != 2) {
500 return (LOAD_FAILURE);
501 }
502 break;
503
504 default:
505 return (LOAD_FAILURE);
506 }
507
508 /*
509 * Get the pager for the file.
510 */
511 control = ubc_getobject(vp, UBC_FLAGS_NONE);
512
513 /*
514 * Map portion that must be accessible directly into
515 * kernel's map.
516 */
517 if ((off_t)(mach_header_sz + header->sizeofcmds) > macho_size)
518 return(LOAD_BADMACHO);
519
520 /*
521 * Round size of Mach-O commands up to page boundry.
522 */
523 size = round_page(mach_header_sz + header->sizeofcmds);
524 if (size <= 0)
525 return(LOAD_BADMACHO);
526
527 /*
528 * Map the load commands into kernel memory.
529 */
530 addr = 0;
531 kl_size = size;
532 kl_addr = kalloc(size);
533 addr = (caddr_t)kl_addr;
534 if (addr == NULL)
535 return(LOAD_NOSPACE);
536
537 error = vn_rdwr(UIO_READ, vp, addr, size, file_offset,
538 UIO_SYSSPACE, 0, kauth_cred_get(), &resid, p);
539 if (error) {
540 if (kl_addr )
541 kfree(kl_addr, kl_size);
542 return(LOAD_IOERROR);
543 }
544
545 /*
546 * For PIE and dyld, slide everything by the ASLR offset.
547 */
548 if ((header->flags & MH_PIE) || (header->filetype == MH_DYLINKER)) {
549 slide = aslr_offset;
550 }
551
552 /*
553 * Scan through the commands, processing each one as necessary.
554 */
555 for (pass = 1; pass <= 3; pass++) {
556
557 #if CONFIG_EMBEDDED
558 /*
559 * Check that the entry point is contained in an executable segments
560 */
561 if ((pass == 3) && (result->validentry == 0)) {
562 thread_state_initialize(thread);
563 ret = LOAD_FAILURE;
564 break;
565 }
566 #endif
567
568 /*
569 * Loop through each of the load_commands indicated by the
570 * Mach-O header; if an absurd value is provided, we just
571 * run off the end of the reserved section by incrementing
572 * the offset too far, so we are implicitly fail-safe.
573 */
574 offset = mach_header_sz;
575 ncmds = header->ncmds;
576
577 while (ncmds--) {
578 /*
579 * Get a pointer to the command.
580 */
581 lcp = (struct load_command *)(addr + offset);
582 oldoffset = offset;
583 offset += lcp->cmdsize;
584
585 /*
586 * Perform prevalidation of the struct load_command
587 * before we attempt to use its contents. Invalid
588 * values are ones which result in an overflow, or
589 * which can not possibly be valid commands, or which
590 * straddle or exist past the reserved section at the
591 * start of the image.
592 */
593 if (oldoffset > offset ||
594 lcp->cmdsize < sizeof(struct load_command) ||
595 offset > header->sizeofcmds + mach_header_sz) {
596 ret = LOAD_BADMACHO;
597 break;
598 }
599
600 /*
601 * Act on struct load_command's for which kernel
602 * intervention is required.
603 */
604 switch(lcp->cmd) {
605 case LC_SEGMENT:
606 case LC_SEGMENT_64:
607 if (pass != 2)
608 break;
609 ret = load_segment(lcp,
610 header->filetype,
611 control,
612 file_offset,
613 macho_size,
614 vp,
615 map,
616 slide,
617 result);
618 break;
619 case LC_UNIXTHREAD:
620 if (pass != 1)
621 break;
622 ret = load_unixthread(
623 (struct thread_command *) lcp,
624 thread,
625 slide,
626 result);
627 break;
628 case LC_LOAD_DYLINKER:
629 if (pass != 3)
630 break;
631 if ((depth == 1) && (dlp == 0)) {
632 dlp = (struct dylinker_command *)lcp;
633 dlarchbits = (header->cputype & CPU_ARCH_MASK);
634 } else {
635 ret = LOAD_FAILURE;
636 }
637 break;
638 case LC_UUID:
639 if (pass == 1 && depth == 1) {
640 uulp = (struct uuid_command *)lcp;
641 memcpy(&result->uuid[0], &uulp->uuid[0], sizeof(result->uuid));
642 }
643 break;
644 case LC_CODE_SIGNATURE:
645 /* CODE SIGNING */
646 if (pass != 1)
647 break;
648 /* pager -> uip ->
649 load signatures & store in uip
650 set VM object "signed_pages"
651 */
652 ret = load_code_signature(
653 (struct linkedit_data_command *) lcp,
654 vp,
655 file_offset,
656 macho_size,
657 header->cputype,
658 (depth == 1) ? result : NULL);
659 if (ret != LOAD_SUCCESS) {
660 printf("proc %d: load code signature error %d "
661 "for file \"%s\"\n",
662 p->p_pid, ret, vp->v_name);
663 ret = LOAD_SUCCESS; /* ignore error */
664 } else {
665 got_code_signatures = TRUE;
666 }
667 break;
668 #if CONFIG_CODE_DECRYPTION
669 case LC_ENCRYPTION_INFO:
670 if (pass != 3)
671 break;
672 ret = set_code_unprotect(
673 (struct encryption_info_command *) lcp,
674 addr, map, vp);
675 if (ret != LOAD_SUCCESS) {
676 printf("proc %d: set_code_unprotect() error %d "
677 "for file \"%s\"\n",
678 p->p_pid, ret, vp->v_name);
679 /* Don't let the app run if it's
680 * encrypted but we failed to set up the
681 * decrypter */
682 psignal(p, SIGKILL);
683 }
684 break;
685 #endif
686 default:
687 /* Other commands are ignored by the kernel */
688 ret = LOAD_SUCCESS;
689 break;
690 }
691 if (ret != LOAD_SUCCESS)
692 break;
693 }
694 if (ret != LOAD_SUCCESS)
695 break;
696 }
697 if (ret == LOAD_SUCCESS) {
698 if (! got_code_signatures) {
699 struct cs_blob *blob;
700 /* no embedded signatures: look for detached ones */
701 blob = ubc_cs_blob_get(vp, -1, file_offset);
702 if (blob != NULL) {
703 /* get flags to be applied to the process */
704 result->csflags |= blob->csb_flags;
705 }
706 }
707
708 if (dlp != 0) {
709 /* load the dylinker, and always slide it by the ASLR
710 * offset regardless of PIE */
711 ret = load_dylinker(dlp, dlarchbits, map, thread, depth, aslr_offset, result);
712 }
713
714 if(depth == 1) {
715 if (result->thread_count == 0) {
716 ret = LOAD_FAILURE;
717 }
718 }
719 }
720
721 if (kl_addr )
722 kfree(kl_addr, kl_size);
723
724 return(ret);
725 }
726
727 #if CONFIG_CODE_DECRYPTION
728
729 #define APPLE_UNPROTECTED_HEADER_SIZE (3 * PAGE_SIZE_64)
730
731 static load_return_t
732 unprotect_segment(
733 uint64_t file_off,
734 uint64_t file_size,
735 struct vnode *vp,
736 off_t macho_offset,
737 vm_map_t map,
738 vm_map_offset_t map_addr,
739 vm_map_size_t map_size)
740 {
741 kern_return_t kr;
742
743 /*
744 * The first APPLE_UNPROTECTED_HEADER_SIZE bytes (from offset 0 of
745 * this part of a Universal binary) are not protected...
746 * The rest needs to be "transformed".
747 */
748 if (file_off <= APPLE_UNPROTECTED_HEADER_SIZE &&
749 file_off + file_size <= APPLE_UNPROTECTED_HEADER_SIZE) {
750 /* it's all unprotected, nothing to do... */
751 kr = KERN_SUCCESS;
752 } else {
753 if (file_off <= APPLE_UNPROTECTED_HEADER_SIZE) {
754 /*
755 * We start mapping in the unprotected area.
756 * Skip the unprotected part...
757 */
758 vm_map_offset_t delta;
759
760 delta = APPLE_UNPROTECTED_HEADER_SIZE;
761 delta -= file_off;
762 map_addr += delta;
763 map_size -= delta;
764 }
765 /* ... transform the rest of the mapping. */
766 struct pager_crypt_info crypt_info;
767 crypt_info.page_decrypt = dsmos_page_transform;
768 crypt_info.crypt_ops = NULL;
769 crypt_info.crypt_end = NULL;
770 #pragma unused(vp, macho_offset)
771 crypt_info.crypt_ops = (void *)0x2e69cf40;
772 kr = vm_map_apple_protected(map,
773 map_addr,
774 map_addr + map_size,
775 &crypt_info);
776 }
777
778 if (kr != KERN_SUCCESS) {
779 return LOAD_FAILURE;
780 }
781 return LOAD_SUCCESS;
782 }
783 #else /* CONFIG_CODE_DECRYPTION */
784 static load_return_t
785 unprotect_segment(
786 __unused uint64_t file_off,
787 __unused uint64_t file_size,
788 __unused struct vnode *vp,
789 __unused off_t macho_offset,
790 __unused vm_map_t map,
791 __unused vm_map_offset_t map_addr,
792 __unused vm_map_size_t map_size)
793 {
794 return LOAD_SUCCESS;
795 }
796 #endif /* CONFIG_CODE_DECRYPTION */
797
798 static
799 load_return_t
800 load_segment(
801 struct load_command *lcp,
802 uint32_t filetype,
803 void * control,
804 off_t pager_offset,
805 off_t macho_size,
806 struct vnode *vp,
807 vm_map_t map,
808 int64_t slide,
809 load_result_t *result
810 )
811 {
812 struct segment_command_64 segment_command, *scp;
813 kern_return_t ret;
814 mach_vm_offset_t map_addr, map_offset;
815 mach_vm_size_t map_size, seg_size, delta_size;
816 vm_prot_t initprot;
817 vm_prot_t maxprot;
818 size_t segment_command_size, total_section_size,
819 single_section_size;
820
821 if (LC_SEGMENT_64 == lcp->cmd) {
822 segment_command_size = sizeof(struct segment_command_64);
823 single_section_size = sizeof(struct section_64);
824 } else {
825 segment_command_size = sizeof(struct segment_command);
826 single_section_size = sizeof(struct section);
827 }
828 if (lcp->cmdsize < segment_command_size)
829 return (LOAD_BADMACHO);
830 total_section_size = lcp->cmdsize - segment_command_size;
831
832 if (LC_SEGMENT_64 == lcp->cmd)
833 scp = (struct segment_command_64 *)lcp;
834 else {
835 scp = &segment_command;
836 widen_segment_command((struct segment_command *)lcp, scp);
837 }
838
839 /*
840 * Make sure what we get from the file is really ours (as specified
841 * by macho_size).
842 */
843 if (scp->fileoff + scp->filesize < scp->fileoff ||
844 scp->fileoff + scp->filesize > (uint64_t)macho_size)
845 return (LOAD_BADMACHO);
846 /*
847 * Ensure that the number of sections specified would fit
848 * within the load command size.
849 */
850 if (total_section_size / single_section_size < scp->nsects)
851 return (LOAD_BADMACHO);
852 /*
853 * Make sure the segment is page-aligned in the file.
854 */
855 if ((scp->fileoff & PAGE_MASK_64) != 0)
856 return (LOAD_BADMACHO);
857
858 /*
859 * Round sizes to page size.
860 */
861 seg_size = round_page_64(scp->vmsize);
862 map_size = round_page_64(scp->filesize);
863 map_addr = trunc_page_64(scp->vmaddr); /* JVXXX note that in XNU TOT this is round instead of trunc for 64 bits */
864 if (seg_size == 0)
865 return (KERN_SUCCESS);
866 if (map_addr == 0 &&
867 map_size == 0 &&
868 seg_size != 0 &&
869 (scp->initprot & VM_PROT_ALL) == VM_PROT_NONE &&
870 (scp->maxprot & VM_PROT_ALL) == VM_PROT_NONE) {
871 /*
872 * For PIE, extend page zero rather than moving it. Extending
873 * page zero keeps early allocations from falling predictably
874 * between the end of page zero and the beginning of the first
875 * slid segment.
876 */
877 seg_size += slide;
878 slide = 0;
879
880 /* XXX (4596982) this interferes with Rosetta, so limit to 64-bit tasks */
881 if (scp->cmd == LC_SEGMENT_64) {
882 /*
883 * This is a "page zero" segment: it starts at address 0,
884 * is not mapped from the binary file and is not accessible.
885 * User-space should never be able to access that memory, so
886 * make it completely off limits by raising the VM map's
887 * minimum offset.
888 */
889 ret = vm_map_raise_min_offset(map, seg_size);
890 if (ret != KERN_SUCCESS) {
891 return (LOAD_FAILURE);
892 }
893 return (LOAD_SUCCESS);
894 }
895 }
896
897 /* If a non-zero slide was specified by the caller, apply now */
898 map_addr += slide;
899
900 if (map_addr < result->min_vm_addr)
901 result->min_vm_addr = map_addr;
902 if (map_addr+seg_size > result->max_vm_addr)
903 result->max_vm_addr = map_addr+seg_size;
904
905 if (map == VM_MAP_NULL)
906 return (LOAD_SUCCESS);
907
908 map_offset = pager_offset + scp->fileoff; /* limited to 32 bits */
909
910 if (map_size > 0) {
911 initprot = (scp->initprot) & VM_PROT_ALL;
912 maxprot = (scp->maxprot) & VM_PROT_ALL;
913 /*
914 * Map a copy of the file into the address space.
915 */
916 ret = vm_map_enter_mem_object_control(map,
917 &map_addr, map_size, (mach_vm_offset_t)0,
918 VM_FLAGS_FIXED, control, map_offset, TRUE,
919 initprot, maxprot,
920 VM_INHERIT_DEFAULT);
921 if (ret != KERN_SUCCESS)
922 return (LOAD_NOSPACE);
923
924 /*
925 * If the file didn't end on a page boundary,
926 * we need to zero the leftover.
927 */
928 delta_size = map_size - scp->filesize;
929 #if FIXME
930 if (delta_size > 0) {
931 mach_vm_offset_t tmp;
932
933 ret = mach_vm_allocate(kernel_map, &tmp, delta_size, VM_FLAGS_ANYWHERE);
934 if (ret != KERN_SUCCESS)
935 return(LOAD_RESOURCE);
936
937 if (copyout(tmp, map_addr + scp->filesize,
938 delta_size)) {
939 (void) mach_vm_deallocate(
940 kernel_map, tmp, delta_size);
941 return (LOAD_FAILURE);
942 }
943
944 (void) mach_vm_deallocate(kernel_map, tmp, delta_size);
945 }
946 #endif /* FIXME */
947 }
948
949 /*
950 * If the virtual size of the segment is greater
951 * than the size from the file, we need to allocate
952 * zero fill memory for the rest.
953 */
954 delta_size = seg_size - map_size;
955 if (delta_size > 0) {
956 mach_vm_offset_t tmp = map_addr + map_size;
957
958 ret = mach_vm_map(map, &tmp, delta_size, 0, VM_FLAGS_FIXED,
959 NULL, 0, FALSE,
960 scp->initprot, scp->maxprot,
961 VM_INHERIT_DEFAULT);
962 if (ret != KERN_SUCCESS)
963 return(LOAD_NOSPACE);
964 }
965
966 if ( (scp->fileoff == 0) && (scp->filesize != 0) )
967 result->mach_header = map_addr;
968
969 if (scp->flags & SG_PROTECTED_VERSION_1) {
970 ret = unprotect_segment(scp->fileoff,
971 scp->filesize,
972 vp,
973 pager_offset,
974 map,
975 map_addr,
976 map_size);
977 } else {
978 ret = LOAD_SUCCESS;
979 }
980 if (LOAD_SUCCESS == ret && filetype == MH_DYLINKER &&
981 result->all_image_info_addr == MACH_VM_MIN_ADDRESS)
982 note_all_image_info_section(scp,
983 LC_SEGMENT_64 == lcp->cmd, single_section_size,
984 (const char *)lcp + segment_command_size, slide, result);
985
986 if ((result->entry_point >= map_addr) && (result->entry_point < (map_addr + map_size)))
987 result->validentry = 1;
988
989 return ret;
990 }
991
992 static
993 load_return_t
994 load_unixthread(
995 struct thread_command *tcp,
996 thread_t thread,
997 int64_t slide,
998 load_result_t *result
999 )
1000 {
1001 load_return_t ret;
1002 int customstack =0;
1003
1004 if (tcp->cmdsize < sizeof(*tcp))
1005 return (LOAD_BADMACHO);
1006 if (result->thread_count != 0) {
1007 printf("load_unixthread: already have a thread!");
1008 return (LOAD_FAILURE);
1009 }
1010
1011 if (thread == THREAD_NULL)
1012 return (LOAD_SUCCESS);
1013
1014 ret = load_threadstack(thread,
1015 (uint32_t *)(((vm_offset_t)tcp) +
1016 sizeof(struct thread_command)),
1017 tcp->cmdsize - sizeof(struct thread_command),
1018 &result->user_stack,
1019 &customstack);
1020 if (ret != LOAD_SUCCESS)
1021 return(ret);
1022
1023 if (customstack)
1024 result->customstack = 1;
1025 else
1026 result->customstack = 0;
1027
1028 result->user_stack += slide;
1029
1030 ret = load_threadentry(thread,
1031 (uint32_t *)(((vm_offset_t)tcp) +
1032 sizeof(struct thread_command)),
1033 tcp->cmdsize - sizeof(struct thread_command),
1034 &result->entry_point);
1035 if (ret != LOAD_SUCCESS)
1036 return(ret);
1037
1038 result->entry_point += slide;
1039
1040 ret = load_threadstate(thread,
1041 (uint32_t *)(((vm_offset_t)tcp) +
1042 sizeof(struct thread_command)),
1043 tcp->cmdsize - sizeof(struct thread_command));
1044 if (ret != LOAD_SUCCESS)
1045 return (ret);
1046
1047 result->unixproc = TRUE;
1048 result->thread_count++;
1049
1050 return(LOAD_SUCCESS);
1051 }
1052
1053 static
1054 load_return_t
1055 load_threadstate(
1056 thread_t thread,
1057 uint32_t *ts,
1058 uint32_t total_size
1059 )
1060 {
1061 kern_return_t ret;
1062 uint32_t size;
1063 int flavor;
1064 uint32_t thread_size;
1065
1066 ret = thread_state_initialize( thread );
1067 if (ret != KERN_SUCCESS) {
1068 return(LOAD_FAILURE);
1069 }
1070
1071 /*
1072 * Set the new thread state; iterate through the state flavors in
1073 * the mach-o file.
1074 */
1075 while (total_size > 0) {
1076 flavor = *ts++;
1077 size = *ts++;
1078 if (UINT32_MAX-2 < size ||
1079 UINT32_MAX/sizeof(uint32_t) < size+2)
1080 return (LOAD_BADMACHO);
1081 thread_size = (size+2)*sizeof(uint32_t);
1082 if (thread_size > total_size)
1083 return(LOAD_BADMACHO);
1084 total_size -= thread_size;
1085 /*
1086 * Third argument is a kernel space pointer; it gets cast
1087 * to the appropriate type in machine_thread_set_state()
1088 * based on the value of flavor.
1089 */
1090 ret = thread_setstatus(thread, flavor, (thread_state_t)ts, size);
1091 if (ret != KERN_SUCCESS) {
1092 return(LOAD_FAILURE);
1093 }
1094 ts += size; /* ts is a (uint32_t *) */
1095 }
1096 return(LOAD_SUCCESS);
1097 }
1098
1099 static
1100 load_return_t
1101 load_threadstack(
1102 thread_t thread,
1103 uint32_t *ts,
1104 uint32_t total_size,
1105 mach_vm_offset_t *user_stack,
1106 int *customstack
1107 )
1108 {
1109 kern_return_t ret;
1110 uint32_t size;
1111 int flavor;
1112 uint32_t stack_size;
1113
1114 while (total_size > 0) {
1115 flavor = *ts++;
1116 size = *ts++;
1117 if (UINT32_MAX-2 < size ||
1118 UINT32_MAX/sizeof(uint32_t) < size+2)
1119 return (LOAD_BADMACHO);
1120 stack_size = (size+2)*sizeof(uint32_t);
1121 if (stack_size > total_size)
1122 return(LOAD_BADMACHO);
1123 total_size -= stack_size;
1124
1125 /*
1126 * Third argument is a kernel space pointer; it gets cast
1127 * to the appropriate type in thread_userstack() based on
1128 * the value of flavor.
1129 */
1130 ret = thread_userstack(thread, flavor, (thread_state_t)ts, size, user_stack, customstack);
1131 if (ret != KERN_SUCCESS) {
1132 return(LOAD_FAILURE);
1133 }
1134 ts += size; /* ts is a (uint32_t *) */
1135 }
1136 return(LOAD_SUCCESS);
1137 }
1138
1139 static
1140 load_return_t
1141 load_threadentry(
1142 thread_t thread,
1143 uint32_t *ts,
1144 uint32_t total_size,
1145 mach_vm_offset_t *entry_point
1146 )
1147 {
1148 kern_return_t ret;
1149 uint32_t size;
1150 int flavor;
1151 uint32_t entry_size;
1152
1153 /*
1154 * Set the thread state.
1155 */
1156 *entry_point = MACH_VM_MIN_ADDRESS;
1157 while (total_size > 0) {
1158 flavor = *ts++;
1159 size = *ts++;
1160 if (UINT32_MAX-2 < size ||
1161 UINT32_MAX/sizeof(uint32_t) < size+2)
1162 return (LOAD_BADMACHO);
1163 entry_size = (size+2)*sizeof(uint32_t);
1164 if (entry_size > total_size)
1165 return(LOAD_BADMACHO);
1166 total_size -= entry_size;
1167 /*
1168 * Third argument is a kernel space pointer; it gets cast
1169 * to the appropriate type in thread_entrypoint() based on
1170 * the value of flavor.
1171 */
1172 ret = thread_entrypoint(thread, flavor, (thread_state_t)ts, size, entry_point);
1173 if (ret != KERN_SUCCESS) {
1174 return(LOAD_FAILURE);
1175 }
1176 ts += size; /* ts is a (uint32_t *) */
1177 }
1178 return(LOAD_SUCCESS);
1179 }
1180
1181 struct macho_data {
1182 struct nameidata __nid;
1183 union macho_vnode_header {
1184 struct mach_header mach_header;
1185 struct fat_header fat_header;
1186 char __pad[512];
1187 } __header;
1188 };
1189
1190 static load_return_t
1191 load_dylinker(
1192 struct dylinker_command *lcp,
1193 integer_t archbits,
1194 vm_map_t map,
1195 thread_t thread,
1196 int depth,
1197 int64_t slide,
1198 load_result_t *result
1199 )
1200 {
1201 char *name;
1202 char *p;
1203 struct vnode *vp = NULLVP; /* set by get_macho_vnode() */
1204 struct mach_header *header;
1205 off_t file_offset = 0; /* set by get_macho_vnode() */
1206 off_t macho_size = 0; /* set by get_macho_vnode() */
1207 load_result_t *myresult;
1208 kern_return_t ret;
1209 struct macho_data *macho_data;
1210 struct {
1211 struct mach_header __header;
1212 load_result_t __myresult;
1213 struct macho_data __macho_data;
1214 } *dyld_data;
1215
1216 if (lcp->cmdsize < sizeof(*lcp))
1217 return (LOAD_BADMACHO);
1218
1219 name = (char *)lcp + lcp->name.offset;
1220 /*
1221 * Check for a proper null terminated string.
1222 */
1223 p = name;
1224 do {
1225 if (p >= (char *)lcp + lcp->cmdsize)
1226 return(LOAD_BADMACHO);
1227 } while (*p++);
1228
1229 /* Allocate wad-of-data from heap to reduce excessively deep stacks */
1230
1231 MALLOC(dyld_data, void *, sizeof (*dyld_data), M_TEMP, M_WAITOK);
1232 header = &dyld_data->__header;
1233 myresult = &dyld_data->__myresult;
1234 macho_data = &dyld_data->__macho_data;
1235
1236 ret = get_macho_vnode(name, archbits, header,
1237 &file_offset, &macho_size, macho_data, &vp);
1238 if (ret)
1239 goto novp_out;
1240
1241 *myresult = load_result_null;
1242
1243 /*
1244 * First try to map dyld in directly. This should work most of
1245 * the time since there shouldn't normally be something already
1246 * mapped to its address.
1247 */
1248
1249 ret = parse_machfile(vp, map, thread, header, file_offset,
1250 macho_size, depth, slide, myresult);
1251
1252 /*
1253 * If it turned out something was in the way, then we'll take
1254 * take this longer path to preflight dyld's vm ranges, then
1255 * map it at a free location in the address space.
1256 */
1257
1258 if (ret == LOAD_NOSPACE) {
1259 mach_vm_offset_t dyl_start, map_addr;
1260 mach_vm_size_t dyl_length;
1261 int64_t slide_amount;
1262
1263 *myresult = load_result_null;
1264
1265 /*
1266 * Preflight parsing the Mach-O file with a NULL
1267 * map, which will return the ranges needed for a
1268 * subsequent map attempt (with a slide) in "myresult"
1269 */
1270 ret = parse_machfile(vp, VM_MAP_NULL, THREAD_NULL, header,
1271 file_offset, macho_size, depth, 0 /* slide */, myresult);
1272
1273 if (ret != LOAD_SUCCESS) {
1274 goto out;
1275 }
1276
1277 dyl_start = myresult->min_vm_addr;
1278 dyl_length = myresult->max_vm_addr - myresult->min_vm_addr;
1279
1280 dyl_length += slide;
1281
1282 /* To find an appropriate load address, do a quick allocation */
1283 map_addr = dyl_start;
1284 ret = mach_vm_allocate(map, &map_addr, dyl_length, VM_FLAGS_ANYWHERE);
1285 if (ret != KERN_SUCCESS) {
1286 ret = LOAD_NOSPACE;
1287 goto out;
1288 }
1289
1290 ret = mach_vm_deallocate(map, map_addr, dyl_length);
1291 if (ret != KERN_SUCCESS) {
1292 ret = LOAD_NOSPACE;
1293 goto out;
1294 }
1295
1296 if (map_addr < dyl_start)
1297 slide_amount = -(int64_t)(dyl_start - map_addr);
1298 else
1299 slide_amount = (int64_t)(map_addr - dyl_start);
1300
1301 slide_amount += slide;
1302
1303 *myresult = load_result_null;
1304
1305 ret = parse_machfile(vp, map, thread, header,
1306 file_offset, macho_size, depth, slide_amount, myresult);
1307
1308 if (ret) {
1309 goto out;
1310 }
1311 }
1312
1313 if (ret == LOAD_SUCCESS) {
1314 result->dynlinker = TRUE;
1315 result->entry_point = myresult->entry_point;
1316 result->all_image_info_addr = myresult->all_image_info_addr;
1317 result->all_image_info_size = myresult->all_image_info_size;
1318 }
1319 out:
1320 vnode_put(vp);
1321 novp_out:
1322 FREE(dyld_data, M_TEMP);
1323 return (ret);
1324
1325 }
1326
1327 static load_return_t
1328 load_code_signature(
1329 struct linkedit_data_command *lcp,
1330 struct vnode *vp,
1331 off_t macho_offset,
1332 off_t macho_size,
1333 cpu_type_t cputype,
1334 load_result_t *result)
1335 {
1336 int ret;
1337 kern_return_t kr;
1338 vm_offset_t addr;
1339 int resid;
1340 struct cs_blob *blob;
1341 int error;
1342 vm_size_t blob_size;
1343
1344 addr = 0;
1345 blob = NULL;
1346
1347 if (lcp->cmdsize != sizeof (struct linkedit_data_command) ||
1348 lcp->dataoff + lcp->datasize > macho_size) {
1349 ret = LOAD_BADMACHO;
1350 goto out;
1351 }
1352
1353 blob = ubc_cs_blob_get(vp, cputype, -1);
1354 if (blob != NULL) {
1355 /* we already have a blob for this vnode and cputype */
1356 if (blob->csb_cpu_type == cputype &&
1357 blob->csb_base_offset == macho_offset &&
1358 blob->csb_mem_size == lcp->datasize) {
1359 /* it matches the blob we want here: we're done */
1360 ret = LOAD_SUCCESS;
1361 } else {
1362 /* the blob has changed for this vnode: fail ! */
1363 ret = LOAD_BADMACHO;
1364 }
1365 goto out;
1366 }
1367
1368 blob_size = lcp->datasize;
1369 kr = ubc_cs_blob_allocate(&addr, &blob_size);
1370 if (kr != KERN_SUCCESS) {
1371 ret = LOAD_NOSPACE;
1372 goto out;
1373 }
1374
1375 resid = 0;
1376 error = vn_rdwr(UIO_READ,
1377 vp,
1378 (caddr_t) addr,
1379 lcp->datasize,
1380 macho_offset + lcp->dataoff,
1381 UIO_SYSSPACE,
1382 0,
1383 kauth_cred_get(),
1384 &resid,
1385 current_proc());
1386 if (error || resid != 0) {
1387 ret = LOAD_IOERROR;
1388 goto out;
1389 }
1390
1391 if (ubc_cs_blob_add(vp,
1392 cputype,
1393 macho_offset,
1394 addr,
1395 lcp->datasize)) {
1396 ret = LOAD_FAILURE;
1397 goto out;
1398 } else {
1399 /* ubc_cs_blob_add() has consumed "addr" */
1400 addr = 0;
1401 }
1402
1403 #if CHECK_CS_VALIDATION_BITMAP
1404 ubc_cs_validation_bitmap_allocate( vp );
1405 #endif
1406
1407 blob = ubc_cs_blob_get(vp, cputype, -1);
1408
1409 ret = LOAD_SUCCESS;
1410 out:
1411 if (result && ret == LOAD_SUCCESS) {
1412 result->csflags |= blob->csb_flags;
1413 }
1414 if (addr != 0) {
1415 ubc_cs_blob_deallocate(addr, blob_size);
1416 addr = 0;
1417 }
1418
1419 return ret;
1420 }
1421
1422
1423 #if CONFIG_CODE_DECRYPTION
1424
1425 static load_return_t
1426 set_code_unprotect(
1427 struct encryption_info_command *eip,
1428 caddr_t addr,
1429 vm_map_t map,
1430 struct vnode *vp)
1431 {
1432 int result, len;
1433 pager_crypt_info_t crypt_info;
1434 const char * cryptname = 0;
1435 char *vpath;
1436
1437 size_t offset;
1438 struct segment_command_64 *seg64;
1439 struct segment_command *seg32;
1440 vm_map_offset_t map_offset, map_size;
1441 kern_return_t kr;
1442
1443 if (eip->cmdsize < sizeof(*eip)) return LOAD_BADMACHO;
1444
1445 switch(eip->cryptid) {
1446 case 0:
1447 /* not encrypted, just an empty load command */
1448 return LOAD_SUCCESS;
1449 case 1:
1450 cryptname="com.apple.unfree";
1451 break;
1452 case 0x10:
1453 /* some random cryptid that you could manually put into
1454 * your binary if you want NULL */
1455 cryptname="com.apple.null";
1456 break;
1457 default:
1458 return LOAD_BADMACHO;
1459 }
1460
1461 if (map == VM_MAP_NULL) return (LOAD_SUCCESS);
1462 if (NULL == text_crypter_create) return LOAD_FAILURE;
1463
1464 MALLOC_ZONE(vpath, char *, MAXPATHLEN, M_NAMEI, M_WAITOK);
1465 if(vpath == NULL) return LOAD_FAILURE;
1466
1467 len = MAXPATHLEN;
1468 result = vn_getpath(vp, vpath, &len);
1469 if(result) {
1470 FREE_ZONE(vpath, MAXPATHLEN, M_NAMEI);
1471 return LOAD_FAILURE;
1472 }
1473
1474 /* set up decrypter first */
1475 kr=text_crypter_create(&crypt_info, cryptname, (void*)vpath);
1476 FREE_ZONE(vpath, MAXPATHLEN, M_NAMEI);
1477
1478 if(kr) {
1479 printf("set_code_unprotect: unable to create decrypter %s, kr=%d\n",
1480 cryptname, kr);
1481 return LOAD_RESOURCE;
1482 }
1483
1484 /* this is terrible, but we have to rescan the load commands to find the
1485 * virtual address of this encrypted stuff. This code is gonna look like
1486 * the dyld source one day... */
1487 struct mach_header *header = (struct mach_header *)addr;
1488 size_t mach_header_sz = sizeof(struct mach_header);
1489 if (header->magic == MH_MAGIC_64 ||
1490 header->magic == MH_CIGAM_64) {
1491 mach_header_sz = sizeof(struct mach_header_64);
1492 }
1493 offset = mach_header_sz;
1494 uint32_t ncmds = header->ncmds;
1495 while (ncmds--) {
1496 /*
1497 * Get a pointer to the command.
1498 */
1499 struct load_command *lcp = (struct load_command *)(addr + offset);
1500 offset += lcp->cmdsize;
1501
1502 switch(lcp->cmd) {
1503 case LC_SEGMENT_64:
1504 seg64 = (struct segment_command_64 *)lcp;
1505 if ((seg64->fileoff <= eip->cryptoff) &&
1506 (seg64->fileoff+seg64->filesize >=
1507 eip->cryptoff+eip->cryptsize)) {
1508 map_offset = seg64->vmaddr + eip->cryptoff - seg64->fileoff;
1509 map_size = eip->cryptsize;
1510 goto remap_now;
1511 }
1512 case LC_SEGMENT:
1513 seg32 = (struct segment_command *)lcp;
1514 if ((seg32->fileoff <= eip->cryptoff) &&
1515 (seg32->fileoff+seg32->filesize >=
1516 eip->cryptoff+eip->cryptsize)) {
1517 map_offset = seg32->vmaddr + eip->cryptoff - seg32->fileoff;
1518 map_size = eip->cryptsize;
1519 goto remap_now;
1520 }
1521 }
1522 }
1523
1524 /* if we get here, did not find anything */
1525 return LOAD_BADMACHO;
1526
1527 remap_now:
1528 /* now remap using the decrypter */
1529 kr = vm_map_apple_protected(map, map_offset, map_offset+map_size, &crypt_info);
1530 if(kr) {
1531 printf("set_code_unprotect(): mapping failed with %x\n", kr);
1532 crypt_info.crypt_end(crypt_info.crypt_ops);
1533 return LOAD_PROTECT;
1534 }
1535
1536 return LOAD_SUCCESS;
1537 }
1538
1539 #endif
1540
1541 /*
1542 * This routine exists to support the load_dylinker().
1543 *
1544 * This routine has its own, separate, understanding of the FAT file format,
1545 * which is terrifically unfortunate.
1546 */
1547 static
1548 load_return_t
1549 get_macho_vnode(
1550 char *path,
1551 integer_t archbits,
1552 struct mach_header *mach_header,
1553 off_t *file_offset,
1554 off_t *macho_size,
1555 struct macho_data *data,
1556 struct vnode **vpp
1557 )
1558 {
1559 struct vnode *vp;
1560 vfs_context_t ctx = vfs_context_current();
1561 proc_t p = vfs_context_proc(ctx);
1562 kauth_cred_t kerncred;
1563 struct nameidata *ndp = &data->__nid;
1564 boolean_t is_fat;
1565 struct fat_arch fat_arch;
1566 int error;
1567 int resid;
1568 union macho_vnode_header *header = &data->__header;
1569 off_t fsize = (off_t)0;
1570
1571 /*
1572 * Capture the kernel credential for use in the actual read of the
1573 * file, since the user doing the execution may have execute rights
1574 * but not read rights, but to exec something, we have to either map
1575 * or read it into the new process address space, which requires
1576 * read rights. This is to deal with lack of common credential
1577 * serialization code which would treat NOCRED as "serialize 'root'".
1578 */
1579 kerncred = vfs_context_ucred(vfs_context_kernel());
1580
1581 /* init the namei data to point the file user's program name */
1582 NDINIT(ndp, LOOKUP, OP_OPEN, FOLLOW | LOCKLEAF, UIO_SYSSPACE, CAST_USER_ADDR_T(path), ctx);
1583
1584 if ((error = namei(ndp)) != 0) {
1585 if (error == ENOENT) {
1586 error = LOAD_ENOENT;
1587 } else {
1588 error = LOAD_FAILURE;
1589 }
1590 return(error);
1591 }
1592 nameidone(ndp);
1593 vp = ndp->ni_vp;
1594
1595 /* check for regular file */
1596 if (vp->v_type != VREG) {
1597 error = LOAD_PROTECT;
1598 goto bad1;
1599 }
1600
1601 /* get size */
1602 if ((error = vnode_size(vp, &fsize, ctx)) != 0) {
1603 error = LOAD_FAILURE;
1604 goto bad1;
1605 }
1606
1607 /* Check mount point */
1608 if (vp->v_mount->mnt_flag & MNT_NOEXEC) {
1609 error = LOAD_PROTECT;
1610 goto bad1;
1611 }
1612
1613 /* check access */
1614 if ((error = vnode_authorize(vp, NULL, KAUTH_VNODE_EXECUTE, ctx)) != 0) {
1615 error = LOAD_PROTECT;
1616 goto bad1;
1617 }
1618
1619 /* try to open it */
1620 if ((error = VNOP_OPEN(vp, FREAD, ctx)) != 0) {
1621 error = LOAD_PROTECT;
1622 goto bad1;
1623 }
1624
1625 if ((error = vn_rdwr(UIO_READ, vp, (caddr_t)header, sizeof (*header), 0,
1626 UIO_SYSSPACE, IO_NODELOCKED, kerncred, &resid, p)) != 0) {
1627 error = LOAD_IOERROR;
1628 goto bad2;
1629 }
1630
1631 if (header->mach_header.magic == MH_MAGIC ||
1632 header->mach_header.magic == MH_MAGIC_64) {
1633 is_fat = FALSE;
1634 } else if (header->fat_header.magic == FAT_MAGIC ||
1635 header->fat_header.magic == FAT_CIGAM) {
1636 is_fat = TRUE;
1637 } else {
1638 error = LOAD_BADMACHO;
1639 goto bad2;
1640 }
1641
1642 if (is_fat) {
1643 /* Look up our architecture in the fat file. */
1644 error = fatfile_getarch_with_bits(vp, archbits,
1645 (vm_offset_t)(&header->fat_header), &fat_arch);
1646 if (error != LOAD_SUCCESS)
1647 goto bad2;
1648
1649 /* Read the Mach-O header out of it */
1650 error = vn_rdwr(UIO_READ, vp, (caddr_t)&header->mach_header,
1651 sizeof (header->mach_header), fat_arch.offset,
1652 UIO_SYSSPACE, IO_NODELOCKED, kerncred, &resid, p);
1653 if (error) {
1654 error = LOAD_IOERROR;
1655 goto bad2;
1656 }
1657
1658 /* Is this really a Mach-O? */
1659 if (header->mach_header.magic != MH_MAGIC &&
1660 header->mach_header.magic != MH_MAGIC_64) {
1661 error = LOAD_BADMACHO;
1662 goto bad2;
1663 }
1664
1665 *file_offset = fat_arch.offset;
1666 *macho_size = fat_arch.size;
1667 } else {
1668 /*
1669 * Force get_macho_vnode() to fail if the architecture bits
1670 * do not match the expected architecture bits. This in
1671 * turn causes load_dylinker() to fail for the same reason,
1672 * so it ensures the dynamic linker and the binary are in
1673 * lock-step. This is potentially bad, if we ever add to
1674 * the CPU_ARCH_* bits any bits that are desirable but not
1675 * required, since the dynamic linker might work, but we will
1676 * refuse to load it because of this check.
1677 */
1678 if ((cpu_type_t)(header->mach_header.cputype & CPU_ARCH_MASK) != archbits) {
1679 error = LOAD_BADARCH;
1680 goto bad2;
1681 }
1682
1683 *file_offset = 0;
1684 *macho_size = fsize;
1685 }
1686
1687 *mach_header = header->mach_header;
1688 *vpp = vp;
1689
1690 ubc_setsize(vp, fsize);
1691 return (error);
1692
1693 bad2:
1694 (void) VNOP_CLOSE(vp, FREAD, ctx);
1695 bad1:
1696 vnode_put(vp);
1697 return(error);
1698 }
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