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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 #include <sys/codesign.h>
53
54 #include <mach/mach_types.h>
55 #include <mach/vm_map.h> /* vm_allocate() */
56 #include <mach/mach_vm.h> /* mach_vm_allocate() */
57 #include <mach/vm_statistics.h>
58 #include <mach/task.h>
59 #include <mach/thread_act.h>
60
61 #include <machine/vmparam.h>
62 #include <machine/exec.h>
63 #include <machine/pal_routines.h>
64
65 #include <kern/kern_types.h>
66 #include <kern/cpu_number.h>
67 #include <kern/mach_loader.h>
68 #include <kern/mach_fat.h>
69 #include <kern/kalloc.h>
70 #include <kern/task.h>
71 #include <kern/thread.h>
72 #include <kern/page_decrypt.h>
73
74 #include <mach-o/fat.h>
75 #include <mach-o/loader.h>
76
77 #include <vm/pmap.h>
78 #include <vm/vm_map.h>
79 #include <vm/vm_kern.h>
80 #include <vm/vm_pager.h>
81 #include <vm/vnode_pager.h>
82 #include <vm/vm_protos.h>
83 #include <IOKit/IOReturn.h> /* for kIOReturnNotPrivileged */
84
85 /*
86 * XXX vm/pmap.h should not treat these prototypes as MACH_KERNEL_PRIVATE
87 * when KERNEL is defined.
88 */
89 extern pmap_t pmap_create(ledger_t ledger, vm_map_size_t size,
90 boolean_t is_64bit);
91
92 /* XXX should have prototypes in a shared header file */
93 extern int get_map_nentries(vm_map_t);
94
95 extern kern_return_t memory_object_signed(memory_object_control_t control,
96 boolean_t is_signed);
97
98 /* An empty load_result_t */
99 static load_result_t load_result_null = {
100 .mach_header = MACH_VM_MIN_ADDRESS,
101 .entry_point = MACH_VM_MIN_ADDRESS,
102 .user_stack = MACH_VM_MIN_ADDRESS,
103 .user_stack_size = 0,
104 .all_image_info_addr = MACH_VM_MIN_ADDRESS,
105 .all_image_info_size = 0,
106 .thread_count = 0,
107 .unixproc = 0,
108 .dynlinker = 0,
109 .needs_dynlinker = 0,
110 .prog_allocated_stack = 0,
111 .prog_stack_size = 0,
112 .validentry = 0,
113 .csflags = 0,
114 .uuid = { 0 },
115 .min_vm_addr = MACH_VM_MAX_ADDRESS,
116 .max_vm_addr = MACH_VM_MIN_ADDRESS
117 };
118
119 /*
120 * Prototypes of static functions.
121 */
122 static load_return_t
123 parse_machfile(
124 struct vnode *vp,
125 vm_map_t map,
126 thread_t thread,
127 struct mach_header *header,
128 off_t file_offset,
129 off_t macho_size,
130 int depth,
131 int64_t slide,
132 int64_t dyld_slide,
133 load_result_t *result
134 );
135
136 static load_return_t
137 load_segment(
138 struct load_command *lcp,
139 uint32_t filetype,
140 void *control,
141 off_t pager_offset,
142 off_t macho_size,
143 struct vnode *vp,
144 vm_map_t map,
145 int64_t slide,
146 load_result_t *result
147 );
148
149 static load_return_t
150 load_uuid(
151 struct uuid_command *uulp,
152 char *command_end,
153 load_result_t *result
154 );
155
156 static load_return_t
157 load_code_signature(
158 struct linkedit_data_command *lcp,
159 struct vnode *vp,
160 off_t macho_offset,
161 off_t macho_size,
162 cpu_type_t cputype,
163 load_result_t *result);
164
165 #if CONFIG_CODE_DECRYPTION
166 static load_return_t
167 set_code_unprotect(
168 struct encryption_info_command *lcp,
169 caddr_t addr,
170 vm_map_t map,
171 int64_t slide,
172 struct vnode *vp,
173 cpu_type_t cputype,
174 cpu_subtype_t cpusubtype);
175 #endif
176
177 static
178 load_return_t
179 load_main(
180 struct entry_point_command *epc,
181 thread_t thread,
182 int64_t slide,
183 load_result_t *result
184 );
185
186 static load_return_t
187 load_unixthread(
188 struct thread_command *tcp,
189 thread_t thread,
190 int64_t slide,
191 load_result_t *result
192 );
193
194 static load_return_t
195 load_threadstate(
196 thread_t thread,
197 uint32_t *ts,
198 uint32_t total_size
199 );
200
201 static load_return_t
202 load_threadstack(
203 thread_t thread,
204 uint32_t *ts,
205 uint32_t total_size,
206 mach_vm_offset_t *user_stack,
207 int *customstack
208 );
209
210 static load_return_t
211 load_threadentry(
212 thread_t thread,
213 uint32_t *ts,
214 uint32_t total_size,
215 mach_vm_offset_t *entry_point
216 );
217
218 static load_return_t
219 load_dylinker(
220 struct dylinker_command *lcp,
221 integer_t archbits,
222 vm_map_t map,
223 thread_t thread,
224 int depth,
225 int64_t slide,
226 load_result_t *result
227 );
228
229 struct macho_data;
230
231 static load_return_t
232 get_macho_vnode(
233 char *path,
234 integer_t archbits,
235 struct mach_header *mach_header,
236 off_t *file_offset,
237 off_t *macho_size,
238 struct macho_data *macho_data,
239 struct vnode **vpp
240 );
241
242 static inline void
243 widen_segment_command(const struct segment_command *scp32,
244 struct segment_command_64 *scp)
245 {
246 scp->cmd = scp32->cmd;
247 scp->cmdsize = scp32->cmdsize;
248 bcopy(scp32->segname, scp->segname, sizeof(scp->segname));
249 scp->vmaddr = scp32->vmaddr;
250 scp->vmsize = scp32->vmsize;
251 scp->fileoff = scp32->fileoff;
252 scp->filesize = scp32->filesize;
253 scp->maxprot = scp32->maxprot;
254 scp->initprot = scp32->initprot;
255 scp->nsects = scp32->nsects;
256 scp->flags = scp32->flags;
257 }
258
259 static void
260 note_all_image_info_section(const struct segment_command_64 *scp,
261 boolean_t is64, size_t section_size, const void *sections,
262 int64_t slide, load_result_t *result)
263 {
264 const union {
265 struct section s32;
266 struct section_64 s64;
267 } *sectionp;
268 unsigned int i;
269
270 if (strncmp(scp->segname, "__DATA", sizeof(scp->segname)) != 0)
271 return;
272 for (i = 0; i < scp->nsects; ++i) {
273 sectionp = (const void *)
274 ((const char *)sections + section_size * i);
275 if (0 == strncmp(sectionp->s64.sectname, "__all_image_info",
276 sizeof(sectionp->s64.sectname))) {
277 result->all_image_info_addr =
278 is64 ? sectionp->s64.addr : sectionp->s32.addr;
279 result->all_image_info_addr += slide;
280 result->all_image_info_size =
281 is64 ? sectionp->s64.size : sectionp->s32.size;
282 return;
283 }
284 }
285 }
286
287 load_return_t
288 load_machfile(
289 struct image_params *imgp,
290 struct mach_header *header,
291 thread_t thread,
292 vm_map_t new_map,
293 load_result_t *result
294 )
295 {
296 struct vnode *vp = imgp->ip_vp;
297 off_t file_offset = imgp->ip_arch_offset;
298 off_t macho_size = imgp->ip_arch_size;
299 off_t file_size = imgp->ip_vattr->va_data_size;
300
301 pmap_t pmap = 0; /* protected by create_map */
302 vm_map_t map;
303 vm_map_t old_map;
304 task_t old_task = TASK_NULL; /* protected by create_map */
305 load_result_t myresult;
306 load_return_t lret;
307 boolean_t create_map = FALSE;
308 int spawn = (imgp->ip_flags & IMGPF_SPAWN);
309 task_t task = current_task();
310 proc_t p = current_proc();
311 mach_vm_offset_t aslr_offset = 0;
312 mach_vm_offset_t dyld_aslr_offset = 0;
313 kern_return_t kret;
314
315 if (macho_size > file_size) {
316 return(LOAD_BADMACHO);
317 }
318
319 if (new_map == VM_MAP_NULL) {
320 create_map = TRUE;
321 old_task = current_task();
322 }
323
324 /*
325 * If we are spawning, we have created backing objects for the process
326 * already, which include non-lazily creating the task map. So we
327 * are going to switch out the task map with one appropriate for the
328 * bitness of the image being loaded.
329 */
330 if (spawn) {
331 create_map = TRUE;
332 old_task = get_threadtask(thread);
333 }
334
335 if (create_map) {
336 pmap = pmap_create(get_task_ledger(task), (vm_map_size_t) 0,
337 (imgp->ip_flags & IMGPF_IS_64BIT));
338 pal_switch_pmap(thread, pmap, imgp->ip_flags & IMGPF_IS_64BIT);
339 map = vm_map_create(pmap,
340 0,
341 vm_compute_max_offset((imgp->ip_flags & IMGPF_IS_64BIT)),
342 TRUE);
343 } else
344 map = new_map;
345
346 #ifndef CONFIG_ENFORCE_SIGNED_CODE
347 /* This turns off faulting for executable pages, which allows
348 * to circumvent Code Signing Enforcement. The per process
349 * flag (CS_ENFORCEMENT) is not set yet, but we can use the
350 * global flag.
351 */
352 if ( !cs_enforcement(NULL) && (header->flags & MH_ALLOW_STACK_EXECUTION) )
353 vm_map_disable_NX(map);
354 #endif
355
356 /* Forcibly disallow execution from data pages on even if the arch
357 * normally permits it. */
358 if ((header->flags & MH_NO_HEAP_EXECUTION) && !(imgp->ip_flags & IMGPF_ALLOW_DATA_EXEC))
359 vm_map_disallow_data_exec(map);
360
361 /*
362 * Compute a random offset for ASLR, and an independent random offset for dyld.
363 */
364 if (!(imgp->ip_flags & IMGPF_DISABLE_ASLR)) {
365 uint64_t max_slide_pages;
366
367 max_slide_pages = vm_map_get_max_aslr_slide_pages(map);
368
369 aslr_offset = random();
370 aslr_offset %= max_slide_pages;
371 aslr_offset <<= vm_map_page_shift(map);
372
373 dyld_aslr_offset = random();
374 dyld_aslr_offset %= max_slide_pages;
375 dyld_aslr_offset <<= vm_map_page_shift(map);
376 }
377
378 if (!result)
379 result = &myresult;
380
381 *result = load_result_null;
382
383 lret = parse_machfile(vp, map, thread, header, file_offset, macho_size,
384 0, (int64_t)aslr_offset, (int64_t)dyld_aslr_offset, result);
385
386 if (lret != LOAD_SUCCESS) {
387 if (create_map) {
388 vm_map_deallocate(map); /* will lose pmap reference too */
389 }
390 return(lret);
391 }
392
393 /*
394 * For 64-bit users, check for presence of a 4GB page zero
395 * which will enable the kernel to share the user's address space
396 * and hence avoid TLB flushes on kernel entry/exit
397 */
398
399 if ((imgp->ip_flags & IMGPF_IS_64BIT) &&
400 vm_map_has_4GB_pagezero(map)) {
401 vm_map_set_4GB_pagezero(map);
402 }
403 /*
404 * Commit to new map.
405 *
406 * Swap the new map for the old, which consumes our new map
407 * reference but each leaves us responsible for the old_map reference.
408 * That lets us get off the pmap associated with it, and
409 * then we can release it.
410 */
411
412 if (create_map) {
413 /*
414 * If this is an exec, then we are going to destroy the old
415 * task, and it's correct to halt it; if it's spawn, the
416 * task is not yet running, and it makes no sense.
417 */
418 if (!spawn) {
419 /*
420 * Mark the task as halting and start the other
421 * threads towards terminating themselves. Then
422 * make sure any threads waiting for a process
423 * transition get informed that we are committed to
424 * this transition, and then finally complete the
425 * task halting (wait for threads and then cleanup
426 * task resources).
427 *
428 * NOTE: task_start_halt() makes sure that no new
429 * threads are created in the task during the transition.
430 * We need to mark the workqueue as exiting before we
431 * wait for threads to terminate (at the end of which
432 * we no longer have a prohibition on thread creation).
433 *
434 * Finally, clean up any lingering workqueue data structures
435 * that may have been left behind by the workqueue threads
436 * as they exited (and then clean up the work queue itself).
437 */
438 kret = task_start_halt(task);
439 if (kret != KERN_SUCCESS) {
440 return(kret);
441 }
442 proc_transcommit(p, 0);
443 workqueue_mark_exiting(p);
444 task_complete_halt(task);
445 workqueue_exit(p);
446 }
447 old_map = swap_task_map(old_task, thread, map, !spawn);
448 vm_map_clear_4GB_pagezero(old_map);
449 vm_map_deallocate(old_map);
450 }
451 return(LOAD_SUCCESS);
452 }
453
454 /*
455 * The file size of a mach-o file is limited to 32 bits; this is because
456 * this is the limit on the kalloc() of enough bytes for a mach_header and
457 * the contents of its sizeofcmds, which is currently constrained to 32
458 * bits in the file format itself. We read into the kernel buffer the
459 * commands section, and then parse it in order to parse the mach-o file
460 * format load_command segment(s). We are only interested in a subset of
461 * the total set of possible commands. If "map"==VM_MAP_NULL or
462 * "thread"==THREAD_NULL, do not make permament VM modifications,
463 * just preflight the parse.
464 */
465 static
466 load_return_t
467 parse_machfile(
468 struct vnode *vp,
469 vm_map_t map,
470 thread_t thread,
471 struct mach_header *header,
472 off_t file_offset,
473 off_t macho_size,
474 int depth,
475 int64_t aslr_offset,
476 int64_t dyld_aslr_offset,
477 load_result_t *result
478 )
479 {
480 uint32_t ncmds;
481 struct load_command *lcp;
482 struct dylinker_command *dlp = 0;
483 integer_t dlarchbits = 0;
484 void * control;
485 load_return_t ret = LOAD_SUCCESS;
486 caddr_t addr;
487 void * kl_addr;
488 vm_size_t size,kl_size;
489 size_t offset;
490 size_t oldoffset; /* for overflow check */
491 int pass;
492 proc_t p = current_proc(); /* XXXX */
493 int error;
494 int resid=0;
495 size_t mach_header_sz = sizeof(struct mach_header);
496 boolean_t abi64;
497 boolean_t got_code_signatures = FALSE;
498 int64_t slide = 0;
499
500 if (header->magic == MH_MAGIC_64 ||
501 header->magic == MH_CIGAM_64) {
502 mach_header_sz = sizeof(struct mach_header_64);
503 }
504
505 /*
506 * Break infinite recursion
507 */
508 if (depth > 6) {
509 return(LOAD_FAILURE);
510 }
511
512 depth++;
513
514 /*
515 * Check to see if right machine type.
516 */
517 if (((cpu_type_t)(header->cputype & ~CPU_ARCH_MASK) != (cpu_type() & ~CPU_ARCH_MASK)) ||
518 !grade_binary(header->cputype,
519 header->cpusubtype & ~CPU_SUBTYPE_MASK))
520 return(LOAD_BADARCH);
521
522 abi64 = ((header->cputype & CPU_ARCH_ABI64) == CPU_ARCH_ABI64);
523
524 switch (header->filetype) {
525
526 case MH_OBJECT:
527 case MH_EXECUTE:
528 case MH_PRELOAD:
529 if (depth != 1) {
530 return (LOAD_FAILURE);
531 }
532 break;
533
534 case MH_FVMLIB:
535 case MH_DYLIB:
536 if (depth == 1) {
537 return (LOAD_FAILURE);
538 }
539 break;
540
541 case MH_DYLINKER:
542 if (depth != 2) {
543 return (LOAD_FAILURE);
544 }
545 break;
546
547 default:
548 return (LOAD_FAILURE);
549 }
550
551 /*
552 * Get the pager for the file.
553 */
554 control = ubc_getobject(vp, UBC_FLAGS_NONE);
555
556 /*
557 * Map portion that must be accessible directly into
558 * kernel's map.
559 */
560 if ((off_t)(mach_header_sz + header->sizeofcmds) > macho_size)
561 return(LOAD_BADMACHO);
562
563 /*
564 * Round size of Mach-O commands up to page boundry.
565 */
566 size = round_page(mach_header_sz + header->sizeofcmds);
567 if (size <= 0)
568 return(LOAD_BADMACHO);
569
570 /*
571 * Map the load commands into kernel memory.
572 */
573 addr = 0;
574 kl_size = size;
575 kl_addr = kalloc(size);
576 addr = (caddr_t)kl_addr;
577 if (addr == NULL)
578 return(LOAD_NOSPACE);
579
580 error = vn_rdwr(UIO_READ, vp, addr, size, file_offset,
581 UIO_SYSSPACE, 0, kauth_cred_get(), &resid, p);
582 if (error) {
583 if (kl_addr )
584 kfree(kl_addr, kl_size);
585 return(LOAD_IOERROR);
586 }
587
588 /*
589 * For PIE and dyld, slide everything by the ASLR offset.
590 */
591 if ((header->flags & MH_PIE) || (header->filetype == MH_DYLINKER)) {
592 slide = aslr_offset;
593 }
594
595 /*
596 * Scan through the commands, processing each one as necessary.
597 * We parse in three passes through the headers:
598 * 1: thread state, uuid, code signature
599 * 2: segments
600 * 3: dyld, encryption, check entry point
601 */
602
603 for (pass = 1; pass <= 3; pass++) {
604
605 /*
606 * Check that the entry point is contained in an executable segments
607 */
608 if ((pass == 3) && (result->validentry == 0)) {
609 thread_state_initialize(thread);
610 ret = LOAD_FAILURE;
611 break;
612 }
613
614 /*
615 * Loop through each of the load_commands indicated by the
616 * Mach-O header; if an absurd value is provided, we just
617 * run off the end of the reserved section by incrementing
618 * the offset too far, so we are implicitly fail-safe.
619 */
620 offset = mach_header_sz;
621 ncmds = header->ncmds;
622
623 while (ncmds--) {
624 /*
625 * Get a pointer to the command.
626 */
627 lcp = (struct load_command *)(addr + offset);
628 oldoffset = offset;
629 offset += lcp->cmdsize;
630
631 /*
632 * Perform prevalidation of the struct load_command
633 * before we attempt to use its contents. Invalid
634 * values are ones which result in an overflow, or
635 * which can not possibly be valid commands, or which
636 * straddle or exist past the reserved section at the
637 * start of the image.
638 */
639 if (oldoffset > offset ||
640 lcp->cmdsize < sizeof(struct load_command) ||
641 offset > header->sizeofcmds + mach_header_sz) {
642 ret = LOAD_BADMACHO;
643 break;
644 }
645
646 /*
647 * Act on struct load_command's for which kernel
648 * intervention is required.
649 */
650 switch(lcp->cmd) {
651 case LC_SEGMENT:
652 if (pass != 2)
653 break;
654
655 if (abi64) {
656 /*
657 * Having an LC_SEGMENT command for the
658 * wrong ABI is invalid <rdar://problem/11021230>
659 */
660 ret = LOAD_BADMACHO;
661 break;
662 }
663
664 ret = load_segment(lcp,
665 header->filetype,
666 control,
667 file_offset,
668 macho_size,
669 vp,
670 map,
671 slide,
672 result);
673 break;
674 case LC_SEGMENT_64:
675 if (pass != 2)
676 break;
677
678 if (!abi64) {
679 /*
680 * Having an LC_SEGMENT_64 command for the
681 * wrong ABI is invalid <rdar://problem/11021230>
682 */
683 ret = LOAD_BADMACHO;
684 break;
685 }
686
687 ret = load_segment(lcp,
688 header->filetype,
689 control,
690 file_offset,
691 macho_size,
692 vp,
693 map,
694 slide,
695 result);
696 break;
697 case LC_UNIXTHREAD:
698 if (pass != 1)
699 break;
700 ret = load_unixthread(
701 (struct thread_command *) lcp,
702 thread,
703 slide,
704 result);
705 break;
706 case LC_MAIN:
707 if (pass != 1)
708 break;
709 if (depth != 1)
710 break;
711 ret = load_main(
712 (struct entry_point_command *) lcp,
713 thread,
714 slide,
715 result);
716 break;
717 case LC_LOAD_DYLINKER:
718 if (pass != 3)
719 break;
720 if ((depth == 1) && (dlp == 0)) {
721 dlp = (struct dylinker_command *)lcp;
722 dlarchbits = (header->cputype & CPU_ARCH_MASK);
723 } else {
724 ret = LOAD_FAILURE;
725 }
726 break;
727 case LC_UUID:
728 if (pass == 1 && depth == 1) {
729 ret = load_uuid((struct uuid_command *) lcp,
730 (char *)addr + mach_header_sz + header->sizeofcmds,
731 result);
732 }
733 break;
734 case LC_CODE_SIGNATURE:
735 /* CODE SIGNING */
736 if (pass != 1)
737 break;
738 /* pager -> uip ->
739 load signatures & store in uip
740 set VM object "signed_pages"
741 */
742 ret = load_code_signature(
743 (struct linkedit_data_command *) lcp,
744 vp,
745 file_offset,
746 macho_size,
747 header->cputype,
748 (depth == 1) ? result : NULL);
749 if (ret != LOAD_SUCCESS) {
750 printf("proc %d: load code signature error %d "
751 "for file \"%s\"\n",
752 p->p_pid, ret, vp->v_name);
753 ret = LOAD_SUCCESS; /* ignore error */
754 } else {
755 got_code_signatures = TRUE;
756 }
757 break;
758 #if CONFIG_CODE_DECRYPTION
759 case LC_ENCRYPTION_INFO:
760 case LC_ENCRYPTION_INFO_64:
761 if (pass != 3)
762 break;
763 ret = set_code_unprotect(
764 (struct encryption_info_command *) lcp,
765 addr, map, slide, vp,
766 header->cputype, header->cpusubtype);
767 if (ret != LOAD_SUCCESS) {
768 printf("proc %d: set_code_unprotect() error %d "
769 "for file \"%s\"\n",
770 p->p_pid, ret, vp->v_name);
771 /*
772 * Don't let the app run if it's
773 * encrypted but we failed to set up the
774 * decrypter. If the keys are missing it will
775 * return LOAD_DECRYPTFAIL.
776 */
777 if (ret == LOAD_DECRYPTFAIL) {
778 /* failed to load due to missing FP keys */
779 proc_lock(p);
780 p->p_lflag |= P_LTERM_DECRYPTFAIL;
781 proc_unlock(p);
782 }
783 psignal(p, SIGKILL);
784 }
785 break;
786 #endif
787 default:
788 /* Other commands are ignored by the kernel */
789 ret = LOAD_SUCCESS;
790 break;
791 }
792 if (ret != LOAD_SUCCESS)
793 break;
794 }
795 if (ret != LOAD_SUCCESS)
796 break;
797 }
798 if (ret == LOAD_SUCCESS) {
799 if (! got_code_signatures) {
800 struct cs_blob *blob;
801 /* no embedded signatures: look for detached ones */
802 blob = ubc_cs_blob_get(vp, -1, file_offset);
803 if (blob != NULL) {
804 /* get flags to be applied to the process */
805 result->csflags |= blob->csb_flags;
806 }
807 }
808
809 /* Make sure if we need dyld, we got it */
810 if (result->needs_dynlinker && !dlp) {
811 ret = LOAD_FAILURE;
812 }
813
814 if ((ret == LOAD_SUCCESS) && (dlp != 0)) {
815 /*
816 * load the dylinker, and slide it by the independent DYLD ASLR
817 * offset regardless of the PIE-ness of the main binary.
818 */
819
820 ret = load_dylinker(dlp, dlarchbits, map, thread, depth,
821 dyld_aslr_offset, result);
822 }
823
824 if((ret == LOAD_SUCCESS) && (depth == 1)) {
825 if (result->thread_count == 0) {
826 ret = LOAD_FAILURE;
827 }
828 }
829 }
830
831 if (kl_addr )
832 kfree(kl_addr, kl_size);
833
834 return(ret);
835 }
836
837 #if CONFIG_CODE_DECRYPTION
838
839 #define APPLE_UNPROTECTED_HEADER_SIZE (3 * PAGE_SIZE_64)
840
841 static load_return_t
842 unprotect_segment(
843 uint64_t file_off,
844 uint64_t file_size,
845 struct vnode *vp,
846 off_t macho_offset,
847 vm_map_t map,
848 vm_map_offset_t map_addr,
849 vm_map_size_t map_size)
850 {
851 kern_return_t kr;
852
853 /*
854 * The first APPLE_UNPROTECTED_HEADER_SIZE bytes (from offset 0 of
855 * this part of a Universal binary) are not protected...
856 * The rest needs to be "transformed".
857 */
858 if (file_off <= APPLE_UNPROTECTED_HEADER_SIZE &&
859 file_off + file_size <= APPLE_UNPROTECTED_HEADER_SIZE) {
860 /* it's all unprotected, nothing to do... */
861 kr = KERN_SUCCESS;
862 } else {
863 if (file_off <= APPLE_UNPROTECTED_HEADER_SIZE) {
864 /*
865 * We start mapping in the unprotected area.
866 * Skip the unprotected part...
867 */
868 vm_map_offset_t delta;
869
870 delta = APPLE_UNPROTECTED_HEADER_SIZE;
871 delta -= file_off;
872 map_addr += delta;
873 map_size -= delta;
874 }
875 /* ... transform the rest of the mapping. */
876 struct pager_crypt_info crypt_info;
877 crypt_info.page_decrypt = dsmos_page_transform;
878 crypt_info.crypt_ops = NULL;
879 crypt_info.crypt_end = NULL;
880 #pragma unused(vp, macho_offset)
881 crypt_info.crypt_ops = (void *)0x2e69cf40;
882 kr = vm_map_apple_protected(map,
883 map_addr,
884 map_addr + map_size,
885 &crypt_info);
886 }
887
888 if (kr != KERN_SUCCESS) {
889 return LOAD_FAILURE;
890 }
891 return LOAD_SUCCESS;
892 }
893 #else /* CONFIG_CODE_DECRYPTION */
894 static load_return_t
895 unprotect_segment(
896 __unused uint64_t file_off,
897 __unused uint64_t file_size,
898 __unused struct vnode *vp,
899 __unused off_t macho_offset,
900 __unused vm_map_t map,
901 __unused vm_map_offset_t map_addr,
902 __unused vm_map_size_t map_size)
903 {
904 return LOAD_SUCCESS;
905 }
906 #endif /* CONFIG_CODE_DECRYPTION */
907
908 static
909 load_return_t
910 load_segment(
911 struct load_command *lcp,
912 uint32_t filetype,
913 void * control,
914 off_t pager_offset,
915 off_t macho_size,
916 struct vnode *vp,
917 vm_map_t map,
918 int64_t slide,
919 load_result_t *result
920 )
921 {
922 struct segment_command_64 segment_command, *scp;
923 kern_return_t ret;
924 vm_map_offset_t map_addr, map_offset;
925 vm_map_size_t map_size, seg_size, delta_size;
926 vm_prot_t initprot;
927 vm_prot_t maxprot;
928 size_t segment_command_size, total_section_size,
929 single_section_size;
930 boolean_t prohibit_pagezero_mapping = FALSE;
931
932 if (LC_SEGMENT_64 == lcp->cmd) {
933 segment_command_size = sizeof(struct segment_command_64);
934 single_section_size = sizeof(struct section_64);
935 } else {
936 segment_command_size = sizeof(struct segment_command);
937 single_section_size = sizeof(struct section);
938 }
939 if (lcp->cmdsize < segment_command_size)
940 return (LOAD_BADMACHO);
941 total_section_size = lcp->cmdsize - segment_command_size;
942
943 if (LC_SEGMENT_64 == lcp->cmd)
944 scp = (struct segment_command_64 *)lcp;
945 else {
946 scp = &segment_command;
947 widen_segment_command((struct segment_command *)lcp, scp);
948 }
949
950 /*
951 * Make sure what we get from the file is really ours (as specified
952 * by macho_size).
953 */
954 if (scp->fileoff + scp->filesize < scp->fileoff ||
955 scp->fileoff + scp->filesize > (uint64_t)macho_size)
956 return (LOAD_BADMACHO);
957 /*
958 * Ensure that the number of sections specified would fit
959 * within the load command size.
960 */
961 if (total_section_size / single_section_size < scp->nsects)
962 return (LOAD_BADMACHO);
963 /*
964 * Make sure the segment is page-aligned in the file.
965 */
966 if ((scp->fileoff & PAGE_MASK_64) != 0)
967 return (LOAD_BADMACHO);
968
969 /*
970 * Round sizes to page size.
971 */
972 seg_size = round_page_64(scp->vmsize);
973 map_size = round_page_64(scp->filesize);
974 map_addr = trunc_page_64(scp->vmaddr); /* JVXXX note that in XNU TOT this is round instead of trunc for 64 bits */
975
976 seg_size = vm_map_round_page(seg_size, vm_map_page_mask(map));
977 map_size = vm_map_round_page(map_size, vm_map_page_mask(map));
978
979 if (seg_size == 0)
980 return (KERN_SUCCESS);
981 if (map_addr == 0 &&
982 map_size == 0 &&
983 seg_size != 0 &&
984 (scp->initprot & VM_PROT_ALL) == VM_PROT_NONE &&
985 (scp->maxprot & VM_PROT_ALL) == VM_PROT_NONE) {
986 /*
987 * For PIE, extend page zero rather than moving it. Extending
988 * page zero keeps early allocations from falling predictably
989 * between the end of page zero and the beginning of the first
990 * slid segment.
991 */
992 seg_size += slide;
993 slide = 0;
994 /* XXX (4596982) this interferes with Rosetta, so limit to 64-bit tasks */
995 if (scp->cmd == LC_SEGMENT_64) {
996 prohibit_pagezero_mapping = TRUE;
997 }
998
999 if (prohibit_pagezero_mapping) {
1000 /*
1001 * This is a "page zero" segment: it starts at address 0,
1002 * is not mapped from the binary file and is not accessible.
1003 * User-space should never be able to access that memory, so
1004 * make it completely off limits by raising the VM map's
1005 * minimum offset.
1006 */
1007 ret = vm_map_raise_min_offset(map, seg_size);
1008 if (ret != KERN_SUCCESS) {
1009 return (LOAD_FAILURE);
1010 }
1011 return (LOAD_SUCCESS);
1012 }
1013 }
1014
1015 /* If a non-zero slide was specified by the caller, apply now */
1016 map_addr += slide;
1017
1018 if (map_addr < result->min_vm_addr)
1019 result->min_vm_addr = map_addr;
1020 if (map_addr+seg_size > result->max_vm_addr)
1021 result->max_vm_addr = map_addr+seg_size;
1022
1023 if (map == VM_MAP_NULL)
1024 return (LOAD_SUCCESS);
1025
1026 map_offset = pager_offset + scp->fileoff; /* limited to 32 bits */
1027
1028 if (map_size > 0) {
1029 initprot = (scp->initprot) & VM_PROT_ALL;
1030 maxprot = (scp->maxprot) & VM_PROT_ALL;
1031 /*
1032 * Map a copy of the file into the address space.
1033 */
1034 ret = vm_map_enter_mem_object_control(map,
1035 &map_addr, map_size, (mach_vm_offset_t)0,
1036 VM_FLAGS_FIXED, control, map_offset, TRUE,
1037 initprot, maxprot,
1038 VM_INHERIT_DEFAULT);
1039 if (ret != KERN_SUCCESS) {
1040 return (LOAD_NOSPACE);
1041 }
1042
1043 /*
1044 * If the file didn't end on a page boundary,
1045 * we need to zero the leftover.
1046 */
1047 delta_size = map_size - scp->filesize;
1048 #if FIXME
1049 if (delta_size > 0) {
1050 mach_vm_offset_t tmp;
1051
1052 ret = mach_vm_allocate(kernel_map, &tmp, delta_size, VM_FLAGS_ANYWHERE);
1053 if (ret != KERN_SUCCESS)
1054 return(LOAD_RESOURCE);
1055
1056 if (copyout(tmp, map_addr + scp->filesize,
1057 delta_size)) {
1058 (void) mach_vm_deallocate(
1059 kernel_map, tmp, delta_size);
1060 return (LOAD_FAILURE);
1061 }
1062
1063 (void) mach_vm_deallocate(kernel_map, tmp, delta_size);
1064 }
1065 #endif /* FIXME */
1066 }
1067
1068 /*
1069 * If the virtual size of the segment is greater
1070 * than the size from the file, we need to allocate
1071 * zero fill memory for the rest.
1072 */
1073 delta_size = seg_size - map_size;
1074 if (delta_size > 0) {
1075 mach_vm_offset_t tmp = map_addr + map_size;
1076
1077 ret = mach_vm_map(map, &tmp, delta_size, 0, VM_FLAGS_FIXED,
1078 NULL, 0, FALSE,
1079 scp->initprot, scp->maxprot,
1080 VM_INHERIT_DEFAULT);
1081 if (ret != KERN_SUCCESS)
1082 return(LOAD_NOSPACE);
1083 }
1084
1085 if ( (scp->fileoff == 0) && (scp->filesize != 0) )
1086 result->mach_header = map_addr;
1087
1088 if (scp->flags & SG_PROTECTED_VERSION_1) {
1089 ret = unprotect_segment(scp->fileoff,
1090 scp->filesize,
1091 vp,
1092 pager_offset,
1093 map,
1094 map_addr,
1095 map_size);
1096 } else {
1097 ret = LOAD_SUCCESS;
1098 }
1099 if (LOAD_SUCCESS == ret && filetype == MH_DYLINKER &&
1100 result->all_image_info_addr == MACH_VM_MIN_ADDRESS)
1101 note_all_image_info_section(scp,
1102 LC_SEGMENT_64 == lcp->cmd, single_section_size,
1103 (const char *)lcp + segment_command_size, slide, result);
1104
1105 if ((result->entry_point >= map_addr) && (result->entry_point < (map_addr + map_size)))
1106 result->validentry = 1;
1107
1108 return ret;
1109 }
1110
1111 static
1112 load_return_t
1113 load_uuid(
1114 struct uuid_command *uulp,
1115 char *command_end,
1116 load_result_t *result
1117 )
1118 {
1119 /*
1120 * We need to check the following for this command:
1121 * - The command size should be atleast the size of struct uuid_command
1122 * - The UUID part of the command should be completely within the mach-o header
1123 */
1124
1125 if ((uulp->cmdsize < sizeof(struct uuid_command)) ||
1126 (((char *)uulp + sizeof(struct uuid_command)) > command_end)) {
1127 return (LOAD_BADMACHO);
1128 }
1129
1130 memcpy(&result->uuid[0], &uulp->uuid[0], sizeof(result->uuid));
1131 return (LOAD_SUCCESS);
1132 }
1133
1134 static
1135 load_return_t
1136 load_main(
1137 struct entry_point_command *epc,
1138 thread_t thread,
1139 int64_t slide,
1140 load_result_t *result
1141 )
1142 {
1143 mach_vm_offset_t addr;
1144 kern_return_t ret;
1145
1146 if (epc->cmdsize < sizeof(*epc))
1147 return (LOAD_BADMACHO);
1148 if (result->thread_count != 0) {
1149 printf("load_main: already have a thread!");
1150 return (LOAD_FAILURE);
1151 }
1152
1153 if (thread == THREAD_NULL)
1154 return (LOAD_SUCCESS);
1155
1156 /* LC_MAIN specifies stack size but not location */
1157 if (epc->stacksize) {
1158 result->prog_stack_size = 1;
1159 result->user_stack_size = epc->stacksize;
1160 } else {
1161 result->prog_stack_size = 0;
1162 result->user_stack_size = MAXSSIZ;
1163 }
1164 result->prog_allocated_stack = 0;
1165
1166 /* use default location for stack */
1167 ret = thread_userstackdefault(thread, &addr);
1168 if (ret != KERN_SUCCESS)
1169 return(LOAD_FAILURE);
1170
1171 /* The stack slides down from the default location */
1172 result->user_stack = addr;
1173 result->user_stack -= slide;
1174
1175 /* kernel does *not* use entryoff from LC_MAIN. Dyld uses it. */
1176 result->needs_dynlinker = TRUE;
1177 result->validentry = TRUE;
1178
1179 ret = thread_state_initialize( thread );
1180 if (ret != KERN_SUCCESS) {
1181 return(LOAD_FAILURE);
1182 }
1183
1184 result->unixproc = TRUE;
1185 result->thread_count++;
1186
1187 return(LOAD_SUCCESS);
1188 }
1189
1190
1191 static
1192 load_return_t
1193 load_unixthread(
1194 struct thread_command *tcp,
1195 thread_t thread,
1196 int64_t slide,
1197 load_result_t *result
1198 )
1199 {
1200 load_return_t ret;
1201 int customstack =0;
1202 mach_vm_offset_t addr;
1203
1204 if (tcp->cmdsize < sizeof(*tcp))
1205 return (LOAD_BADMACHO);
1206 if (result->thread_count != 0) {
1207 printf("load_unixthread: already have a thread!");
1208 return (LOAD_FAILURE);
1209 }
1210
1211 if (thread == THREAD_NULL)
1212 return (LOAD_SUCCESS);
1213
1214 ret = load_threadstack(thread,
1215 (uint32_t *)(((vm_offset_t)tcp) +
1216 sizeof(struct thread_command)),
1217 tcp->cmdsize - sizeof(struct thread_command),
1218 &addr,
1219 &customstack);
1220 if (ret != LOAD_SUCCESS)
1221 return(ret);
1222
1223 /* LC_UNIXTHREAD optionally specifies stack size and location */
1224
1225 if (customstack) {
1226 result->prog_stack_size = 0; /* unknown */
1227 result->prog_allocated_stack = 1;
1228 } else {
1229 result->prog_allocated_stack = 0;
1230 result->prog_stack_size = 0;
1231 result->user_stack_size = MAXSSIZ;
1232 }
1233
1234 /* The stack slides down from the default location */
1235 result->user_stack = addr;
1236 result->user_stack -= slide;
1237
1238 ret = load_threadentry(thread,
1239 (uint32_t *)(((vm_offset_t)tcp) +
1240 sizeof(struct thread_command)),
1241 tcp->cmdsize - sizeof(struct thread_command),
1242 &addr);
1243 if (ret != LOAD_SUCCESS)
1244 return(ret);
1245
1246 result->entry_point = addr;
1247 result->entry_point += slide;
1248
1249 ret = load_threadstate(thread,
1250 (uint32_t *)(((vm_offset_t)tcp) +
1251 sizeof(struct thread_command)),
1252 tcp->cmdsize - sizeof(struct thread_command));
1253 if (ret != LOAD_SUCCESS)
1254 return (ret);
1255
1256 result->unixproc = TRUE;
1257 result->thread_count++;
1258
1259 return(LOAD_SUCCESS);
1260 }
1261
1262 static
1263 load_return_t
1264 load_threadstate(
1265 thread_t thread,
1266 uint32_t *ts,
1267 uint32_t total_size
1268 )
1269 {
1270 kern_return_t ret;
1271 uint32_t size;
1272 int flavor;
1273 uint32_t thread_size;
1274
1275 ret = thread_state_initialize( thread );
1276 if (ret != KERN_SUCCESS) {
1277 return(LOAD_FAILURE);
1278 }
1279
1280 /*
1281 * Set the new thread state; iterate through the state flavors in
1282 * the mach-o file.
1283 */
1284 while (total_size > 0) {
1285 flavor = *ts++;
1286 size = *ts++;
1287 if (UINT32_MAX-2 < size ||
1288 UINT32_MAX/sizeof(uint32_t) < size+2)
1289 return (LOAD_BADMACHO);
1290 thread_size = (size+2)*sizeof(uint32_t);
1291 if (thread_size > total_size)
1292 return(LOAD_BADMACHO);
1293 total_size -= thread_size;
1294 /*
1295 * Third argument is a kernel space pointer; it gets cast
1296 * to the appropriate type in machine_thread_set_state()
1297 * based on the value of flavor.
1298 */
1299 ret = thread_setstatus(thread, flavor, (thread_state_t)ts, size);
1300 if (ret != KERN_SUCCESS) {
1301 return(LOAD_FAILURE);
1302 }
1303 ts += size; /* ts is a (uint32_t *) */
1304 }
1305 return(LOAD_SUCCESS);
1306 }
1307
1308 static
1309 load_return_t
1310 load_threadstack(
1311 thread_t thread,
1312 uint32_t *ts,
1313 uint32_t total_size,
1314 mach_vm_offset_t *user_stack,
1315 int *customstack
1316 )
1317 {
1318 kern_return_t ret;
1319 uint32_t size;
1320 int flavor;
1321 uint32_t stack_size;
1322
1323 while (total_size > 0) {
1324 flavor = *ts++;
1325 size = *ts++;
1326 if (UINT32_MAX-2 < size ||
1327 UINT32_MAX/sizeof(uint32_t) < size+2)
1328 return (LOAD_BADMACHO);
1329 stack_size = (size+2)*sizeof(uint32_t);
1330 if (stack_size > total_size)
1331 return(LOAD_BADMACHO);
1332 total_size -= stack_size;
1333
1334 /*
1335 * Third argument is a kernel space pointer; it gets cast
1336 * to the appropriate type in thread_userstack() based on
1337 * the value of flavor.
1338 */
1339 ret = thread_userstack(thread, flavor, (thread_state_t)ts, size, user_stack, customstack);
1340 if (ret != KERN_SUCCESS) {
1341 return(LOAD_FAILURE);
1342 }
1343 ts += size; /* ts is a (uint32_t *) */
1344 }
1345 return(LOAD_SUCCESS);
1346 }
1347
1348 static
1349 load_return_t
1350 load_threadentry(
1351 thread_t thread,
1352 uint32_t *ts,
1353 uint32_t total_size,
1354 mach_vm_offset_t *entry_point
1355 )
1356 {
1357 kern_return_t ret;
1358 uint32_t size;
1359 int flavor;
1360 uint32_t entry_size;
1361
1362 /*
1363 * Set the thread state.
1364 */
1365 *entry_point = MACH_VM_MIN_ADDRESS;
1366 while (total_size > 0) {
1367 flavor = *ts++;
1368 size = *ts++;
1369 if (UINT32_MAX-2 < size ||
1370 UINT32_MAX/sizeof(uint32_t) < size+2)
1371 return (LOAD_BADMACHO);
1372 entry_size = (size+2)*sizeof(uint32_t);
1373 if (entry_size > total_size)
1374 return(LOAD_BADMACHO);
1375 total_size -= entry_size;
1376 /*
1377 * Third argument is a kernel space pointer; it gets cast
1378 * to the appropriate type in thread_entrypoint() based on
1379 * the value of flavor.
1380 */
1381 ret = thread_entrypoint(thread, flavor, (thread_state_t)ts, size, entry_point);
1382 if (ret != KERN_SUCCESS) {
1383 return(LOAD_FAILURE);
1384 }
1385 ts += size; /* ts is a (uint32_t *) */
1386 }
1387 return(LOAD_SUCCESS);
1388 }
1389
1390 struct macho_data {
1391 struct nameidata __nid;
1392 union macho_vnode_header {
1393 struct mach_header mach_header;
1394 struct fat_header fat_header;
1395 char __pad[512];
1396 } __header;
1397 };
1398
1399 static load_return_t
1400 load_dylinker(
1401 struct dylinker_command *lcp,
1402 integer_t archbits,
1403 vm_map_t map,
1404 thread_t thread,
1405 int depth,
1406 int64_t slide,
1407 load_result_t *result
1408 )
1409 {
1410 char *name;
1411 char *p;
1412 struct vnode *vp = NULLVP; /* set by get_macho_vnode() */
1413 struct mach_header *header;
1414 off_t file_offset = 0; /* set by get_macho_vnode() */
1415 off_t macho_size = 0; /* set by get_macho_vnode() */
1416 load_result_t *myresult;
1417 kern_return_t ret;
1418 struct macho_data *macho_data;
1419 struct {
1420 struct mach_header __header;
1421 load_result_t __myresult;
1422 struct macho_data __macho_data;
1423 } *dyld_data;
1424
1425 if (lcp->cmdsize < sizeof(*lcp))
1426 return (LOAD_BADMACHO);
1427
1428 name = (char *)lcp + lcp->name.offset;
1429 /*
1430 * Check for a proper null terminated string.
1431 */
1432 p = name;
1433 do {
1434 if (p >= (char *)lcp + lcp->cmdsize)
1435 return(LOAD_BADMACHO);
1436 } while (*p++);
1437
1438 /* Allocate wad-of-data from heap to reduce excessively deep stacks */
1439
1440 MALLOC(dyld_data, void *, sizeof (*dyld_data), M_TEMP, M_WAITOK);
1441 header = &dyld_data->__header;
1442 myresult = &dyld_data->__myresult;
1443 macho_data = &dyld_data->__macho_data;
1444
1445 ret = get_macho_vnode(name, archbits, header,
1446 &file_offset, &macho_size, macho_data, &vp);
1447 if (ret)
1448 goto novp_out;
1449
1450 *myresult = load_result_null;
1451
1452 /*
1453 * First try to map dyld in directly. This should work most of
1454 * the time since there shouldn't normally be something already
1455 * mapped to its address.
1456 */
1457
1458 ret = parse_machfile(vp, map, thread, header, file_offset,
1459 macho_size, depth, slide, 0, myresult);
1460
1461 /*
1462 * If it turned out something was in the way, then we'll take
1463 * take this longer path to preflight dyld's vm ranges, then
1464 * map it at a free location in the address space.
1465 */
1466
1467 if (ret == LOAD_NOSPACE) {
1468 mach_vm_offset_t dyl_start, map_addr;
1469 mach_vm_size_t dyl_length;
1470 int64_t slide_amount;
1471
1472 *myresult = load_result_null;
1473
1474 /*
1475 * Preflight parsing the Mach-O file with a NULL
1476 * map, which will return the ranges needed for a
1477 * subsequent map attempt (with a slide) in "myresult"
1478 */
1479 ret = parse_machfile(vp, VM_MAP_NULL, THREAD_NULL, header,
1480 file_offset, macho_size, depth,
1481 0 /* slide */, 0, myresult);
1482
1483 if (ret != LOAD_SUCCESS) {
1484 goto out;
1485 }
1486
1487 dyl_start = myresult->min_vm_addr;
1488 dyl_length = myresult->max_vm_addr - myresult->min_vm_addr;
1489
1490 dyl_length += slide;
1491
1492 /* To find an appropriate load address, do a quick allocation */
1493 map_addr = dyl_start;
1494 ret = mach_vm_allocate(map, &map_addr, dyl_length, VM_FLAGS_ANYWHERE);
1495 if (ret != KERN_SUCCESS) {
1496 ret = LOAD_NOSPACE;
1497 goto out;
1498 }
1499
1500 ret = mach_vm_deallocate(map, map_addr, dyl_length);
1501 if (ret != KERN_SUCCESS) {
1502 ret = LOAD_NOSPACE;
1503 goto out;
1504 }
1505
1506 if (map_addr < dyl_start)
1507 slide_amount = -(int64_t)(dyl_start - map_addr);
1508 else
1509 slide_amount = (int64_t)(map_addr - dyl_start);
1510
1511 slide_amount += slide;
1512
1513 *myresult = load_result_null;
1514
1515 ret = parse_machfile(vp, map, thread, header,
1516 file_offset, macho_size, depth,
1517 slide_amount, 0, myresult);
1518
1519 if (ret) {
1520 goto out;
1521 }
1522 }
1523
1524 if (ret == LOAD_SUCCESS) {
1525 result->dynlinker = TRUE;
1526 result->entry_point = myresult->entry_point;
1527 result->validentry = myresult->validentry;
1528 result->all_image_info_addr = myresult->all_image_info_addr;
1529 result->all_image_info_size = myresult->all_image_info_size;
1530 }
1531 out:
1532 vnode_put(vp);
1533 novp_out:
1534 FREE(dyld_data, M_TEMP);
1535 return (ret);
1536
1537 }
1538
1539 static load_return_t
1540 load_code_signature(
1541 struct linkedit_data_command *lcp,
1542 struct vnode *vp,
1543 off_t macho_offset,
1544 off_t macho_size,
1545 cpu_type_t cputype,
1546 load_result_t *result)
1547 {
1548 int ret;
1549 kern_return_t kr;
1550 vm_offset_t addr;
1551 int resid;
1552 struct cs_blob *blob;
1553 int error;
1554 vm_size_t blob_size;
1555
1556 addr = 0;
1557 blob = NULL;
1558
1559 if (lcp->cmdsize != sizeof (struct linkedit_data_command) ||
1560 lcp->dataoff + lcp->datasize > macho_size) {
1561 ret = LOAD_BADMACHO;
1562 goto out;
1563 }
1564
1565 blob = ubc_cs_blob_get(vp, cputype, -1);
1566 if (blob != NULL &&
1567 blob->csb_cpu_type == cputype &&
1568 blob->csb_base_offset == macho_offset &&
1569 blob->csb_blob_offset == lcp->dataoff &&
1570 blob->csb_mem_size == lcp->datasize) {
1571 /*
1572 * we already have a blob for this vnode and cputype
1573 * and its at the same offset in Mach-O. Optimize to
1574 * not reload, revalidate, and compare the blob hashes.
1575 * Security will not be compromised, but we might miss
1576 * out on some messagetracer info about the differences
1577 * in blob content.
1578 */
1579 ret = LOAD_SUCCESS;
1580 goto out;
1581 }
1582
1583 blob_size = lcp->datasize;
1584 kr = ubc_cs_blob_allocate(&addr, &blob_size);
1585 if (kr != KERN_SUCCESS) {
1586 ret = LOAD_NOSPACE;
1587 goto out;
1588 }
1589
1590 resid = 0;
1591 error = vn_rdwr(UIO_READ,
1592 vp,
1593 (caddr_t) addr,
1594 lcp->datasize,
1595 macho_offset + lcp->dataoff,
1596 UIO_SYSSPACE,
1597 0,
1598 kauth_cred_get(),
1599 &resid,
1600 current_proc());
1601 if (error || resid != 0) {
1602 ret = LOAD_IOERROR;
1603 goto out;
1604 }
1605
1606 if (ubc_cs_blob_add(vp,
1607 cputype,
1608 macho_offset,
1609 addr,
1610 lcp->dataoff,
1611 lcp->datasize)) {
1612 ret = LOAD_FAILURE;
1613 goto out;
1614 } else {
1615 /* ubc_cs_blob_add() has consumed "addr" */
1616 addr = 0;
1617 }
1618
1619 #if CHECK_CS_VALIDATION_BITMAP
1620 ubc_cs_validation_bitmap_allocate( vp );
1621 #endif
1622
1623 blob = ubc_cs_blob_get(vp, cputype, -1);
1624
1625 ret = LOAD_SUCCESS;
1626 out:
1627 if (result && ret == LOAD_SUCCESS) {
1628 result->csflags |= blob->csb_flags;
1629 }
1630 if (addr != 0) {
1631 ubc_cs_blob_deallocate(addr, blob_size);
1632 addr = 0;
1633 }
1634
1635 return ret;
1636 }
1637
1638
1639 #if CONFIG_CODE_DECRYPTION
1640
1641 static load_return_t
1642 set_code_unprotect(
1643 struct encryption_info_command *eip,
1644 caddr_t addr,
1645 vm_map_t map,
1646 int64_t slide,
1647 struct vnode *vp,
1648 cpu_type_t cputype,
1649 cpu_subtype_t cpusubtype)
1650 {
1651 int result, len;
1652 pager_crypt_info_t crypt_info;
1653 const char * cryptname = 0;
1654 char *vpath;
1655
1656 size_t offset;
1657 struct segment_command_64 *seg64;
1658 struct segment_command *seg32;
1659 vm_map_offset_t map_offset, map_size;
1660 kern_return_t kr;
1661
1662 if (eip->cmdsize < sizeof(*eip)) return LOAD_BADMACHO;
1663
1664 switch(eip->cryptid) {
1665 case 0:
1666 /* not encrypted, just an empty load command */
1667 return LOAD_SUCCESS;
1668 case 1:
1669 cryptname="com.apple.unfree";
1670 break;
1671 case 0x10:
1672 /* some random cryptid that you could manually put into
1673 * your binary if you want NULL */
1674 cryptname="com.apple.null";
1675 break;
1676 default:
1677 return LOAD_BADMACHO;
1678 }
1679
1680 if (map == VM_MAP_NULL) return (LOAD_SUCCESS);
1681 if (NULL == text_crypter_create) return LOAD_FAILURE;
1682
1683 MALLOC_ZONE(vpath, char *, MAXPATHLEN, M_NAMEI, M_WAITOK);
1684 if(vpath == NULL) return LOAD_FAILURE;
1685
1686 len = MAXPATHLEN;
1687 result = vn_getpath(vp, vpath, &len);
1688 if(result) {
1689 FREE_ZONE(vpath, MAXPATHLEN, M_NAMEI);
1690 return LOAD_FAILURE;
1691 }
1692
1693 /* set up decrypter first */
1694 crypt_file_data_t crypt_data = {
1695 .filename = vpath,
1696 .cputype = cputype,
1697 .cpusubtype = cpusubtype};
1698 kr=text_crypter_create(&crypt_info, cryptname, (void*)&crypt_data);
1699 FREE_ZONE(vpath, MAXPATHLEN, M_NAMEI);
1700
1701 if(kr) {
1702 printf("set_code_unprotect: unable to create decrypter %s, kr=%d\n",
1703 cryptname, kr);
1704 if (kr == kIOReturnNotPrivileged) {
1705 /* text encryption returned decryption failure */
1706 return(LOAD_DECRYPTFAIL);
1707 }else
1708 return LOAD_RESOURCE;
1709 }
1710
1711 /* this is terrible, but we have to rescan the load commands to find the
1712 * virtual address of this encrypted stuff. This code is gonna look like
1713 * the dyld source one day... */
1714 struct mach_header *header = (struct mach_header *)addr;
1715 size_t mach_header_sz = sizeof(struct mach_header);
1716 if (header->magic == MH_MAGIC_64 ||
1717 header->magic == MH_CIGAM_64) {
1718 mach_header_sz = sizeof(struct mach_header_64);
1719 }
1720 offset = mach_header_sz;
1721 uint32_t ncmds = header->ncmds;
1722 while (ncmds--) {
1723 /*
1724 * Get a pointer to the command.
1725 */
1726 struct load_command *lcp = (struct load_command *)(addr + offset);
1727 offset += lcp->cmdsize;
1728
1729 switch(lcp->cmd) {
1730 case LC_SEGMENT_64:
1731 seg64 = (struct segment_command_64 *)lcp;
1732 if ((seg64->fileoff <= eip->cryptoff) &&
1733 (seg64->fileoff+seg64->filesize >=
1734 eip->cryptoff+eip->cryptsize)) {
1735 map_offset = seg64->vmaddr + eip->cryptoff - seg64->fileoff + slide;
1736 map_size = eip->cryptsize;
1737 goto remap_now;
1738 }
1739 case LC_SEGMENT:
1740 seg32 = (struct segment_command *)lcp;
1741 if ((seg32->fileoff <= eip->cryptoff) &&
1742 (seg32->fileoff+seg32->filesize >=
1743 eip->cryptoff+eip->cryptsize)) {
1744 map_offset = seg32->vmaddr + eip->cryptoff - seg32->fileoff + slide;
1745 map_size = eip->cryptsize;
1746 goto remap_now;
1747 }
1748 }
1749 }
1750
1751 /* if we get here, did not find anything */
1752 return LOAD_BADMACHO;
1753
1754 remap_now:
1755 /* now remap using the decrypter */
1756 kr = vm_map_apple_protected(map, map_offset, map_offset+map_size, &crypt_info);
1757 if(kr) {
1758 printf("set_code_unprotect(): mapping failed with %x\n", kr);
1759 crypt_info.crypt_end(crypt_info.crypt_ops);
1760 return LOAD_PROTECT;
1761 }
1762
1763 return LOAD_SUCCESS;
1764 }
1765
1766 #endif
1767
1768 /*
1769 * This routine exists to support the load_dylinker().
1770 *
1771 * This routine has its own, separate, understanding of the FAT file format,
1772 * which is terrifically unfortunate.
1773 */
1774 static
1775 load_return_t
1776 get_macho_vnode(
1777 char *path,
1778 integer_t archbits,
1779 struct mach_header *mach_header,
1780 off_t *file_offset,
1781 off_t *macho_size,
1782 struct macho_data *data,
1783 struct vnode **vpp
1784 )
1785 {
1786 struct vnode *vp;
1787 vfs_context_t ctx = vfs_context_current();
1788 proc_t p = vfs_context_proc(ctx);
1789 kauth_cred_t kerncred;
1790 struct nameidata *ndp = &data->__nid;
1791 boolean_t is_fat;
1792 struct fat_arch fat_arch;
1793 int error;
1794 int resid;
1795 union macho_vnode_header *header = &data->__header;
1796 off_t fsize = (off_t)0;
1797
1798 /*
1799 * Capture the kernel credential for use in the actual read of the
1800 * file, since the user doing the execution may have execute rights
1801 * but not read rights, but to exec something, we have to either map
1802 * or read it into the new process address space, which requires
1803 * read rights. This is to deal with lack of common credential
1804 * serialization code which would treat NOCRED as "serialize 'root'".
1805 */
1806 kerncred = vfs_context_ucred(vfs_context_kernel());
1807
1808 /* init the namei data to point the file user's program name */
1809 NDINIT(ndp, LOOKUP, OP_OPEN, FOLLOW | LOCKLEAF, UIO_SYSSPACE, CAST_USER_ADDR_T(path), ctx);
1810
1811 if ((error = namei(ndp)) != 0) {
1812 if (error == ENOENT) {
1813 error = LOAD_ENOENT;
1814 } else {
1815 error = LOAD_FAILURE;
1816 }
1817 return(error);
1818 }
1819 nameidone(ndp);
1820 vp = ndp->ni_vp;
1821
1822 /* check for regular file */
1823 if (vp->v_type != VREG) {
1824 error = LOAD_PROTECT;
1825 goto bad1;
1826 }
1827
1828 /* get size */
1829 if ((error = vnode_size(vp, &fsize, ctx)) != 0) {
1830 error = LOAD_FAILURE;
1831 goto bad1;
1832 }
1833
1834 /* Check mount point */
1835 if (vp->v_mount->mnt_flag & MNT_NOEXEC) {
1836 error = LOAD_PROTECT;
1837 goto bad1;
1838 }
1839
1840 /* check access */
1841 if ((error = vnode_authorize(vp, NULL, KAUTH_VNODE_EXECUTE | KAUTH_VNODE_READ_DATA, ctx)) != 0) {
1842 error = LOAD_PROTECT;
1843 goto bad1;
1844 }
1845
1846 /* try to open it */
1847 if ((error = VNOP_OPEN(vp, FREAD, ctx)) != 0) {
1848 error = LOAD_PROTECT;
1849 goto bad1;
1850 }
1851
1852 if ((error = vn_rdwr(UIO_READ, vp, (caddr_t)header, sizeof (*header), 0,
1853 UIO_SYSSPACE, IO_NODELOCKED, kerncred, &resid, p)) != 0) {
1854 error = LOAD_IOERROR;
1855 goto bad2;
1856 }
1857
1858 if (header->mach_header.magic == MH_MAGIC ||
1859 header->mach_header.magic == MH_MAGIC_64) {
1860 is_fat = FALSE;
1861 } else if (header->fat_header.magic == FAT_MAGIC ||
1862 header->fat_header.magic == FAT_CIGAM) {
1863 is_fat = TRUE;
1864 } else {
1865 error = LOAD_BADMACHO;
1866 goto bad2;
1867 }
1868
1869 if (is_fat) {
1870 /* Look up our architecture in the fat file. */
1871 error = fatfile_getarch_with_bits(vp, archbits,
1872 (vm_offset_t)(&header->fat_header), &fat_arch);
1873 if (error != LOAD_SUCCESS)
1874 goto bad2;
1875
1876 /* Read the Mach-O header out of it */
1877 error = vn_rdwr(UIO_READ, vp, (caddr_t)&header->mach_header,
1878 sizeof (header->mach_header), fat_arch.offset,
1879 UIO_SYSSPACE, IO_NODELOCKED, kerncred, &resid, p);
1880 if (error) {
1881 error = LOAD_IOERROR;
1882 goto bad2;
1883 }
1884
1885 /* Is this really a Mach-O? */
1886 if (header->mach_header.magic != MH_MAGIC &&
1887 header->mach_header.magic != MH_MAGIC_64) {
1888 error = LOAD_BADMACHO;
1889 goto bad2;
1890 }
1891
1892 *file_offset = fat_arch.offset;
1893 *macho_size = fat_arch.size;
1894 } else {
1895 /*
1896 * Force get_macho_vnode() to fail if the architecture bits
1897 * do not match the expected architecture bits. This in
1898 * turn causes load_dylinker() to fail for the same reason,
1899 * so it ensures the dynamic linker and the binary are in
1900 * lock-step. This is potentially bad, if we ever add to
1901 * the CPU_ARCH_* bits any bits that are desirable but not
1902 * required, since the dynamic linker might work, but we will
1903 * refuse to load it because of this check.
1904 */
1905 if ((cpu_type_t)(header->mach_header.cputype & CPU_ARCH_MASK) != archbits) {
1906 error = LOAD_BADARCH;
1907 goto bad2;
1908 }
1909
1910 *file_offset = 0;
1911 *macho_size = fsize;
1912 }
1913
1914 *mach_header = header->mach_header;
1915 *vpp = vp;
1916
1917 ubc_setsize(vp, fsize);
1918 return (error);
1919
1920 bad2:
1921 (void) VNOP_CLOSE(vp, FREAD, ctx);
1922 bad1:
1923 vnode_put(vp);
1924 return(error);
1925 }
mirror of XNU