1 | /* |
2 | * Copyright (c) 1999-2020 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 | * File: ubc_subr.c |
30 | * Author: Umesh Vaishampayan [umeshv@apple.com] |
31 | * 05-Aug-1999 umeshv Created. |
32 | * |
33 | * Functions related to Unified Buffer cache. |
34 | * |
35 | * Caller of UBC functions MUST have a valid reference on the vnode. |
36 | * |
37 | */ |
38 | |
39 | #include <sys/types.h> |
40 | #include <sys/param.h> |
41 | #include <sys/systm.h> |
42 | #include <sys/lock.h> |
43 | #include <sys/mman.h> |
44 | #include <sys/mount_internal.h> |
45 | #include <sys/vnode_internal.h> |
46 | #include <sys/ubc_internal.h> |
47 | #include <sys/ucred.h> |
48 | #include <sys/proc_internal.h> |
49 | #include <sys/kauth.h> |
50 | #include <sys/buf.h> |
51 | #include <sys/user.h> |
52 | #include <sys/codesign.h> |
53 | #include <sys/codedir_internal.h> |
54 | #include <sys/fsevents.h> |
55 | #include <sys/fcntl.h> |
56 | #include <sys/reboot.h> |
57 | #include <sys/code_signing.h> |
58 | |
59 | #include <mach/mach_types.h> |
60 | #include <mach/memory_object_types.h> |
61 | #include <mach/memory_object_control.h> |
62 | #include <mach/vm_map.h> |
63 | #include <mach/mach_vm.h> |
64 | #include <mach/upl.h> |
65 | |
66 | #include <kern/kern_types.h> |
67 | #include <kern/kalloc.h> |
68 | #include <kern/zalloc.h> |
69 | #include <kern/thread.h> |
70 | #include <vm/pmap.h> |
71 | #include <vm/vm_kern.h> |
72 | #include <vm/vm_protos.h> /* last */ |
73 | |
74 | #include <libkern/crypto/sha1.h> |
75 | #include <libkern/crypto/sha2.h> |
76 | #include <libkern/libkern.h> |
77 | |
78 | #include <security/mac_framework.h> |
79 | #include <stdbool.h> |
80 | #include <stdatomic.h> |
81 | #include <libkern/amfi/amfi.h> |
82 | |
83 | /* XXX These should be in a BSD accessible Mach header, but aren't. */ |
84 | extern kern_return_t memory_object_pages_resident(memory_object_control_t, |
85 | boolean_t *); |
86 | extern kern_return_t memory_object_signed(memory_object_control_t control, |
87 | boolean_t is_signed); |
88 | extern boolean_t memory_object_is_signed(memory_object_control_t); |
89 | extern void memory_object_mark_trusted( |
90 | memory_object_control_t control); |
91 | |
92 | extern void Debugger(const char *message); |
93 | |
94 | #if DIAGNOSTIC |
95 | #if defined(assert) |
96 | #undef assert |
97 | #endif |
98 | #define assert(cond) \ |
99 | ((void) ((cond) ? 0 : panic("Assert failed: %s", # cond))) |
100 | #else |
101 | #include <kern/assert.h> |
102 | #endif /* DIAGNOSTIC */ |
103 | |
104 | static int ubc_info_init_internal(struct vnode *vp, int withfsize, off_t filesize); |
105 | static int ubc_umcallback(vnode_t, void *); |
106 | static int ubc_msync_internal(vnode_t, off_t, off_t, off_t *, int, int *); |
107 | static void ubc_cs_free(struct ubc_info *uip); |
108 | |
109 | static boolean_t ubc_cs_supports_multilevel_hash(struct cs_blob *blob); |
110 | static kern_return_t ubc_cs_convert_to_multilevel_hash(struct cs_blob *blob); |
111 | |
112 | ZONE_DEFINE_TYPE(ubc_info_zone, "ubc_info zone" , struct ubc_info, |
113 | ZC_ZFREE_CLEARMEM); |
114 | static uint32_t cs_blob_generation_count = 1; |
115 | |
116 | /* |
117 | * CODESIGNING |
118 | * Routines to navigate code signing data structures in the kernel... |
119 | */ |
120 | |
121 | ZONE_DEFINE_ID(ZONE_ID_CS_BLOB, "cs_blob zone" , struct cs_blob, |
122 | ZC_READONLY | ZC_ZFREE_CLEARMEM); |
123 | |
124 | extern int cs_debug; |
125 | |
126 | #define PAGE_SHIFT_4K (12) |
127 | |
128 | static boolean_t |
129 | cs_valid_range( |
130 | const void *start, |
131 | const void *end, |
132 | const void *lower_bound, |
133 | const void *upper_bound) |
134 | { |
135 | if (upper_bound < lower_bound || |
136 | end < start) { |
137 | return FALSE; |
138 | } |
139 | |
140 | if (start < lower_bound || |
141 | end > upper_bound) { |
142 | return FALSE; |
143 | } |
144 | |
145 | return TRUE; |
146 | } |
147 | |
148 | typedef void (*cs_md_init)(void *ctx); |
149 | typedef void (*cs_md_update)(void *ctx, const void *data, size_t size); |
150 | typedef void (*cs_md_final)(void *hash, void *ctx); |
151 | |
152 | struct cs_hash { |
153 | uint8_t cs_type; /* type code as per code signing */ |
154 | size_t cs_size; /* size of effective hash (may be truncated) */ |
155 | size_t cs_digest_size;/* size of native hash */ |
156 | cs_md_init cs_init; |
157 | cs_md_update cs_update; |
158 | cs_md_final cs_final; |
159 | }; |
160 | |
161 | uint8_t |
162 | cs_hash_type( |
163 | struct cs_hash const * const cs_hash) |
164 | { |
165 | return cs_hash->cs_type; |
166 | } |
167 | |
168 | static const struct cs_hash cs_hash_sha1 = { |
169 | .cs_type = CS_HASHTYPE_SHA1, |
170 | .cs_size = CS_SHA1_LEN, |
171 | .cs_digest_size = SHA_DIGEST_LENGTH, |
172 | .cs_init = (cs_md_init)SHA1Init, |
173 | .cs_update = (cs_md_update)SHA1Update, |
174 | .cs_final = (cs_md_final)SHA1Final, |
175 | }; |
176 | #if CRYPTO_SHA2 |
177 | static const struct cs_hash cs_hash_sha256 = { |
178 | .cs_type = CS_HASHTYPE_SHA256, |
179 | .cs_size = SHA256_DIGEST_LENGTH, |
180 | .cs_digest_size = SHA256_DIGEST_LENGTH, |
181 | .cs_init = (cs_md_init)SHA256_Init, |
182 | .cs_update = (cs_md_update)SHA256_Update, |
183 | .cs_final = (cs_md_final)SHA256_Final, |
184 | }; |
185 | static const struct cs_hash cs_hash_sha256_truncate = { |
186 | .cs_type = CS_HASHTYPE_SHA256_TRUNCATED, |
187 | .cs_size = CS_SHA256_TRUNCATED_LEN, |
188 | .cs_digest_size = SHA256_DIGEST_LENGTH, |
189 | .cs_init = (cs_md_init)SHA256_Init, |
190 | .cs_update = (cs_md_update)SHA256_Update, |
191 | .cs_final = (cs_md_final)SHA256_Final, |
192 | }; |
193 | static const struct cs_hash cs_hash_sha384 = { |
194 | .cs_type = CS_HASHTYPE_SHA384, |
195 | .cs_size = SHA384_DIGEST_LENGTH, |
196 | .cs_digest_size = SHA384_DIGEST_LENGTH, |
197 | .cs_init = (cs_md_init)SHA384_Init, |
198 | .cs_update = (cs_md_update)SHA384_Update, |
199 | .cs_final = (cs_md_final)SHA384_Final, |
200 | }; |
201 | #endif |
202 | |
203 | static struct cs_hash const * |
204 | cs_find_md(uint8_t type) |
205 | { |
206 | if (type == CS_HASHTYPE_SHA1) { |
207 | return &cs_hash_sha1; |
208 | #if CRYPTO_SHA2 |
209 | } else if (type == CS_HASHTYPE_SHA256) { |
210 | return &cs_hash_sha256; |
211 | } else if (type == CS_HASHTYPE_SHA256_TRUNCATED) { |
212 | return &cs_hash_sha256_truncate; |
213 | } else if (type == CS_HASHTYPE_SHA384) { |
214 | return &cs_hash_sha384; |
215 | #endif |
216 | } |
217 | return NULL; |
218 | } |
219 | |
220 | union cs_hash_union { |
221 | SHA1_CTX sha1ctxt; |
222 | SHA256_CTX sha256ctx; |
223 | SHA384_CTX sha384ctx; |
224 | }; |
225 | |
226 | |
227 | /* |
228 | * Choose among different hash algorithms. |
229 | * Higher is better, 0 => don't use at all. |
230 | */ |
231 | static const uint32_t hashPriorities[] = { |
232 | CS_HASHTYPE_SHA1, |
233 | CS_HASHTYPE_SHA256_TRUNCATED, |
234 | CS_HASHTYPE_SHA256, |
235 | CS_HASHTYPE_SHA384, |
236 | }; |
237 | |
238 | static unsigned int |
239 | hash_rank(const CS_CodeDirectory *cd) |
240 | { |
241 | uint32_t type = cd->hashType; |
242 | unsigned int n; |
243 | |
244 | for (n = 0; n < sizeof(hashPriorities) / sizeof(hashPriorities[0]); ++n) { |
245 | if (hashPriorities[n] == type) { |
246 | return n + 1; |
247 | } |
248 | } |
249 | return 0; /* not supported */ |
250 | } |
251 | |
252 | |
253 | /* |
254 | * Locating a page hash |
255 | */ |
256 | static const unsigned char * |
257 | hashes( |
258 | const CS_CodeDirectory *cd, |
259 | uint32_t page, |
260 | size_t hash_len, |
261 | const char *lower_bound, |
262 | const char *upper_bound) |
263 | { |
264 | const unsigned char *base, *top, *hash; |
265 | uint32_t nCodeSlots = ntohl(cd->nCodeSlots); |
266 | |
267 | assert(cs_valid_range(cd, cd + 1, lower_bound, upper_bound)); |
268 | |
269 | if ((ntohl(cd->version) >= CS_SUPPORTSSCATTER) && (ntohl(cd->scatterOffset))) { |
270 | /* Get first scatter struct */ |
271 | const SC_Scatter *scatter = (const SC_Scatter*) |
272 | ((const char*)cd + ntohl(cd->scatterOffset)); |
273 | uint32_t hashindex = 0, scount, sbase = 0; |
274 | /* iterate all scatter structs */ |
275 | do { |
276 | if ((const char*)scatter > (const char*)cd + ntohl(cd->length)) { |
277 | if (cs_debug) { |
278 | printf("CODE SIGNING: Scatter extends past Code Directory\n" ); |
279 | } |
280 | return NULL; |
281 | } |
282 | |
283 | scount = ntohl(scatter->count); |
284 | uint32_t new_base = ntohl(scatter->base); |
285 | |
286 | /* last scatter? */ |
287 | if (scount == 0) { |
288 | return NULL; |
289 | } |
290 | |
291 | if ((hashindex > 0) && (new_base <= sbase)) { |
292 | if (cs_debug) { |
293 | printf("CODE SIGNING: unordered Scatter, prev base %d, cur base %d\n" , |
294 | sbase, new_base); |
295 | } |
296 | return NULL; /* unordered scatter array */ |
297 | } |
298 | sbase = new_base; |
299 | |
300 | /* this scatter beyond page we're looking for? */ |
301 | if (sbase > page) { |
302 | return NULL; |
303 | } |
304 | |
305 | if (sbase + scount >= page) { |
306 | /* Found the scatter struct that is |
307 | * referencing our page */ |
308 | |
309 | /* base = address of first hash covered by scatter */ |
310 | base = (const unsigned char *)cd + ntohl(cd->hashOffset) + |
311 | hashindex * hash_len; |
312 | /* top = address of first hash after this scatter */ |
313 | top = base + scount * hash_len; |
314 | if (!cs_valid_range(start: base, end: top, lower_bound, |
315 | upper_bound) || |
316 | hashindex > nCodeSlots) { |
317 | return NULL; |
318 | } |
319 | |
320 | break; |
321 | } |
322 | |
323 | /* this scatter struct is before the page we're looking |
324 | * for. Iterate. */ |
325 | hashindex += scount; |
326 | scatter++; |
327 | } while (1); |
328 | |
329 | hash = base + (page - sbase) * hash_len; |
330 | } else { |
331 | base = (const unsigned char *)cd + ntohl(cd->hashOffset); |
332 | top = base + nCodeSlots * hash_len; |
333 | if (!cs_valid_range(start: base, end: top, lower_bound, upper_bound) || |
334 | page > nCodeSlots) { |
335 | return NULL; |
336 | } |
337 | assert(page < nCodeSlots); |
338 | |
339 | hash = base + page * hash_len; |
340 | } |
341 | |
342 | if (!cs_valid_range(start: hash, end: hash + hash_len, |
343 | lower_bound, upper_bound)) { |
344 | hash = NULL; |
345 | } |
346 | |
347 | return hash; |
348 | } |
349 | |
350 | /* |
351 | * cs_validate_codedirectory |
352 | * |
353 | * Validate that pointers inside the code directory to make sure that |
354 | * all offsets and lengths are constrained within the buffer. |
355 | * |
356 | * Parameters: cd Pointer to code directory buffer |
357 | * length Length of buffer |
358 | * |
359 | * Returns: 0 Success |
360 | * EBADEXEC Invalid code signature |
361 | */ |
362 | |
363 | static int |
364 | cs_validate_codedirectory(const CS_CodeDirectory *cd, size_t length) |
365 | { |
366 | struct cs_hash const *hashtype; |
367 | |
368 | if (length < sizeof(*cd)) { |
369 | return EBADEXEC; |
370 | } |
371 | if (ntohl(cd->magic) != CSMAGIC_CODEDIRECTORY) { |
372 | return EBADEXEC; |
373 | } |
374 | if ((cd->pageSize != PAGE_SHIFT_4K) && (cd->pageSize != PAGE_SHIFT)) { |
375 | printf("disallowing unsupported code signature page shift: %u\n" , cd->pageSize); |
376 | return EBADEXEC; |
377 | } |
378 | hashtype = cs_find_md(type: cd->hashType); |
379 | if (hashtype == NULL) { |
380 | return EBADEXEC; |
381 | } |
382 | |
383 | if (cd->hashSize != hashtype->cs_size) { |
384 | return EBADEXEC; |
385 | } |
386 | |
387 | if (length < ntohl(cd->hashOffset)) { |
388 | return EBADEXEC; |
389 | } |
390 | |
391 | /* check that nSpecialSlots fits in the buffer in front of hashOffset */ |
392 | if (ntohl(cd->hashOffset) / hashtype->cs_size < ntohl(cd->nSpecialSlots)) { |
393 | return EBADEXEC; |
394 | } |
395 | |
396 | /* check that codeslots fits in the buffer */ |
397 | if ((length - ntohl(cd->hashOffset)) / hashtype->cs_size < ntohl(cd->nCodeSlots)) { |
398 | return EBADEXEC; |
399 | } |
400 | |
401 | if (ntohl(cd->version) >= CS_SUPPORTSSCATTER && cd->scatterOffset) { |
402 | if (length < ntohl(cd->scatterOffset)) { |
403 | return EBADEXEC; |
404 | } |
405 | |
406 | const SC_Scatter *scatter = (const SC_Scatter *) |
407 | (((const uint8_t *)cd) + ntohl(cd->scatterOffset)); |
408 | uint32_t nPages = 0; |
409 | |
410 | /* |
411 | * Check each scatter buffer, since we don't know the |
412 | * length of the scatter buffer array, we have to |
413 | * check each entry. |
414 | */ |
415 | while (1) { |
416 | /* check that the end of each scatter buffer in within the length */ |
417 | if (((const uint8_t *)scatter) + sizeof(scatter[0]) > (const uint8_t *)cd + length) { |
418 | return EBADEXEC; |
419 | } |
420 | uint32_t scount = ntohl(scatter->count); |
421 | if (scount == 0) { |
422 | break; |
423 | } |
424 | if (nPages + scount < nPages) { |
425 | return EBADEXEC; |
426 | } |
427 | nPages += scount; |
428 | scatter++; |
429 | |
430 | /* XXX check that basees doesn't overlap */ |
431 | /* XXX check that targetOffset doesn't overlap */ |
432 | } |
433 | #if 0 /* rdar://12579439 */ |
434 | if (nPages != ntohl(cd->nCodeSlots)) { |
435 | return EBADEXEC; |
436 | } |
437 | #endif |
438 | } |
439 | |
440 | if (length < ntohl(cd->identOffset)) { |
441 | return EBADEXEC; |
442 | } |
443 | |
444 | /* identifier is NUL terminated string */ |
445 | if (cd->identOffset) { |
446 | const uint8_t *ptr = (const uint8_t *)cd + ntohl(cd->identOffset); |
447 | if (memchr(ptr, 0, length - ntohl(cd->identOffset)) == NULL) { |
448 | return EBADEXEC; |
449 | } |
450 | } |
451 | |
452 | /* team identifier is NULL terminated string */ |
453 | if (ntohl(cd->version) >= CS_SUPPORTSTEAMID && ntohl(cd->teamOffset)) { |
454 | if (length < ntohl(cd->teamOffset)) { |
455 | return EBADEXEC; |
456 | } |
457 | |
458 | const uint8_t *ptr = (const uint8_t *)cd + ntohl(cd->teamOffset); |
459 | if (memchr(ptr, 0, length - ntohl(cd->teamOffset)) == NULL) { |
460 | return EBADEXEC; |
461 | } |
462 | } |
463 | |
464 | /* linkage is variable length binary data */ |
465 | if (ntohl(cd->version) >= CS_SUPPORTSLINKAGE && cd->linkageHashType != 0) { |
466 | const uintptr_t ptr = (uintptr_t)cd + ntohl(cd->linkageOffset); |
467 | const uintptr_t ptr_end = ptr + ntohl(cd->linkageSize); |
468 | |
469 | if (ptr_end < ptr || ptr < (uintptr_t)cd || ptr_end > (uintptr_t)cd + length) { |
470 | return EBADEXEC; |
471 | } |
472 | } |
473 | |
474 | |
475 | return 0; |
476 | } |
477 | |
478 | /* |
479 | * |
480 | */ |
481 | |
482 | static int |
483 | cs_validate_blob(const CS_GenericBlob *blob, size_t length) |
484 | { |
485 | if (length < sizeof(CS_GenericBlob) || length < ntohl(blob->length)) { |
486 | return EBADEXEC; |
487 | } |
488 | return 0; |
489 | } |
490 | |
491 | /* |
492 | * cs_validate_csblob |
493 | * |
494 | * Validate that superblob/embedded code directory to make sure that |
495 | * all internal pointers are valid. |
496 | * |
497 | * Will validate both a superblob csblob and a "raw" code directory. |
498 | * |
499 | * |
500 | * Parameters: buffer Pointer to code signature |
501 | * length Length of buffer |
502 | * rcd returns pointer to code directory |
503 | * |
504 | * Returns: 0 Success |
505 | * EBADEXEC Invalid code signature |
506 | */ |
507 | |
508 | static int |
509 | cs_validate_csblob( |
510 | const uint8_t *addr, |
511 | const size_t blob_size, |
512 | const CS_CodeDirectory **rcd, |
513 | const CS_GenericBlob **rentitlements, |
514 | const CS_GenericBlob **rder_entitlements) |
515 | { |
516 | const CS_GenericBlob *blob; |
517 | int error; |
518 | size_t length; |
519 | const CS_GenericBlob *self_constraint = NULL; |
520 | const CS_GenericBlob *parent_constraint = NULL; |
521 | const CS_GenericBlob *responsible_proc_constraint = NULL; |
522 | const CS_GenericBlob *library_constraint = NULL; |
523 | |
524 | *rcd = NULL; |
525 | *rentitlements = NULL; |
526 | *rder_entitlements = NULL; |
527 | |
528 | blob = (const CS_GenericBlob *)(const void *)addr; |
529 | |
530 | length = blob_size; |
531 | error = cs_validate_blob(blob, length); |
532 | if (error) { |
533 | return error; |
534 | } |
535 | length = ntohl(blob->length); |
536 | |
537 | if (ntohl(blob->magic) == CSMAGIC_EMBEDDED_SIGNATURE) { |
538 | const CS_SuperBlob *sb; |
539 | uint32_t n, count; |
540 | const CS_CodeDirectory *best_cd = NULL; |
541 | unsigned int best_rank = 0; |
542 | #if XNU_PLATFORM_WatchOS |
543 | const CS_CodeDirectory *sha1_cd = NULL; |
544 | #endif |
545 | |
546 | if (length < sizeof(CS_SuperBlob)) { |
547 | return EBADEXEC; |
548 | } |
549 | |
550 | sb = (const CS_SuperBlob *)blob; |
551 | count = ntohl(sb->count); |
552 | |
553 | /* check that the array of BlobIndex fits in the rest of the data */ |
554 | if ((length - sizeof(CS_SuperBlob)) / sizeof(CS_BlobIndex) < count) { |
555 | return EBADEXEC; |
556 | } |
557 | |
558 | /* now check each BlobIndex */ |
559 | for (n = 0; n < count; n++) { |
560 | const CS_BlobIndex *blobIndex = &sb->index[n]; |
561 | uint32_t type = ntohl(blobIndex->type); |
562 | uint32_t offset = ntohl(blobIndex->offset); |
563 | if (length < offset) { |
564 | return EBADEXEC; |
565 | } |
566 | |
567 | const CS_GenericBlob *subBlob = |
568 | (const CS_GenericBlob *)(const void *)(addr + offset); |
569 | |
570 | size_t subLength = length - offset; |
571 | |
572 | if ((error = cs_validate_blob(blob: subBlob, length: subLength)) != 0) { |
573 | return error; |
574 | } |
575 | subLength = ntohl(subBlob->length); |
576 | |
577 | /* extra validation for CDs, that is also returned */ |
578 | if (type == CSSLOT_CODEDIRECTORY || (type >= CSSLOT_ALTERNATE_CODEDIRECTORIES && type < CSSLOT_ALTERNATE_CODEDIRECTORY_LIMIT)) { |
579 | const CS_CodeDirectory *candidate = (const CS_CodeDirectory *)subBlob; |
580 | if ((error = cs_validate_codedirectory(cd: candidate, length: subLength)) != 0) { |
581 | return error; |
582 | } |
583 | unsigned int rank = hash_rank(cd: candidate); |
584 | if (cs_debug > 3) { |
585 | printf("CodeDirectory type %d rank %d at slot 0x%x index %d\n" , candidate->hashType, (int)rank, (int)type, (int)n); |
586 | } |
587 | if (best_cd == NULL || rank > best_rank) { |
588 | best_cd = candidate; |
589 | best_rank = rank; |
590 | |
591 | if (cs_debug > 2) { |
592 | printf("using CodeDirectory type %d (rank %d)\n" , (int)best_cd->hashType, best_rank); |
593 | } |
594 | *rcd = best_cd; |
595 | } else if (best_cd != NULL && rank == best_rank) { |
596 | /* repeat of a hash type (1:1 mapped to ranks), illegal and suspicious */ |
597 | printf("multiple hash=%d CodeDirectories in signature; rejecting\n" , best_cd->hashType); |
598 | return EBADEXEC; |
599 | } |
600 | #if XNU_PLATFORM_WatchOS |
601 | if (candidate->hashType == CS_HASHTYPE_SHA1) { |
602 | if (sha1_cd != NULL) { |
603 | printf("multiple sha1 CodeDirectories in signature; rejecting\n" ); |
604 | return EBADEXEC; |
605 | } |
606 | sha1_cd = candidate; |
607 | } |
608 | #endif |
609 | } else if (type == CSSLOT_ENTITLEMENTS) { |
610 | if (ntohl(subBlob->magic) != CSMAGIC_EMBEDDED_ENTITLEMENTS) { |
611 | return EBADEXEC; |
612 | } |
613 | if (*rentitlements != NULL) { |
614 | printf("multiple entitlements blobs\n" ); |
615 | return EBADEXEC; |
616 | } |
617 | *rentitlements = subBlob; |
618 | } else if (type == CSSLOT_DER_ENTITLEMENTS) { |
619 | if (ntohl(subBlob->magic) != CSMAGIC_EMBEDDED_DER_ENTITLEMENTS) { |
620 | return EBADEXEC; |
621 | } |
622 | if (*rder_entitlements != NULL) { |
623 | printf("multiple der entitlements blobs\n" ); |
624 | return EBADEXEC; |
625 | } |
626 | *rder_entitlements = subBlob; |
627 | } else if (type == CSSLOT_LAUNCH_CONSTRAINT_SELF) { |
628 | if (ntohl(subBlob->magic) != CSMAGIC_EMBEDDED_LAUNCH_CONSTRAINT) { |
629 | return EBADEXEC; |
630 | } |
631 | if (self_constraint != NULL) { |
632 | printf("multiple self constraint blobs\n" ); |
633 | return EBADEXEC; |
634 | } |
635 | self_constraint = subBlob; |
636 | } else if (type == CSSLOT_LAUNCH_CONSTRAINT_PARENT) { |
637 | if (ntohl(subBlob->magic) != CSMAGIC_EMBEDDED_LAUNCH_CONSTRAINT) { |
638 | return EBADEXEC; |
639 | } |
640 | if (parent_constraint != NULL) { |
641 | printf("multiple parent constraint blobs\n" ); |
642 | return EBADEXEC; |
643 | } |
644 | parent_constraint = subBlob; |
645 | } else if (type == CSSLOT_LAUNCH_CONSTRAINT_RESPONSIBLE) { |
646 | if (ntohl(subBlob->magic) != CSMAGIC_EMBEDDED_LAUNCH_CONSTRAINT) { |
647 | return EBADEXEC; |
648 | } |
649 | if (responsible_proc_constraint != NULL) { |
650 | printf("multiple responsible process constraint blobs\n" ); |
651 | return EBADEXEC; |
652 | } |
653 | responsible_proc_constraint = subBlob; |
654 | } else if (type == CSSLOT_LIBRARY_CONSTRAINT) { |
655 | if (ntohl(subBlob->magic) != CSMAGIC_EMBEDDED_LAUNCH_CONSTRAINT) { |
656 | return EBADEXEC; |
657 | } |
658 | if (library_constraint != NULL) { |
659 | printf("multiple library constraint blobs\n" ); |
660 | return EBADEXEC; |
661 | } |
662 | library_constraint = subBlob; |
663 | } |
664 | } |
665 | |
666 | #if XNU_PLATFORM_WatchOS |
667 | /* To keep watchOS fast enough, we have to resort to sha1 for |
668 | * some code. |
669 | * |
670 | * At the time of writing this comment, known sha1 attacks are |
671 | * collision attacks (not preimage or second preimage |
672 | * attacks), which do not apply to platform binaries since |
673 | * they have a fixed hash in the trust cache. Given this |
674 | * property, we only prefer sha1 code directories for adhoc |
675 | * signatures, which always have to be in a trust cache to be |
676 | * valid (can-load-cdhash does not exist for watchOS). Those |
677 | * are, incidentally, also the platform binaries, for which we |
678 | * care about the performance hit that sha256 would bring us. |
679 | * |
680 | * Platform binaries may still contain a (not chosen) sha256 |
681 | * code directory, which keeps software updates that switch to |
682 | * sha256-only small. |
683 | */ |
684 | |
685 | if (*rcd != NULL && sha1_cd != NULL && (ntohl(sha1_cd->flags) & CS_ADHOC)) { |
686 | if (sha1_cd->flags != (*rcd)->flags) { |
687 | printf("mismatched flags between hash %d (flags: %#x) and sha1 (flags: %#x) cd.\n" , |
688 | (int)(*rcd)->hashType, (*rcd)->flags, sha1_cd->flags); |
689 | *rcd = NULL; |
690 | return EBADEXEC; |
691 | } |
692 | |
693 | *rcd = sha1_cd; |
694 | } |
695 | #endif |
696 | } else if (ntohl(blob->magic) == CSMAGIC_CODEDIRECTORY) { |
697 | if ((error = cs_validate_codedirectory(cd: (const CS_CodeDirectory *)(const void *)addr, length)) != 0) { |
698 | return error; |
699 | } |
700 | *rcd = (const CS_CodeDirectory *)blob; |
701 | } else { |
702 | return EBADEXEC; |
703 | } |
704 | |
705 | if (*rcd == NULL) { |
706 | return EBADEXEC; |
707 | } |
708 | |
709 | return 0; |
710 | } |
711 | |
712 | /* |
713 | * cs_find_blob_bytes |
714 | * |
715 | * Find an blob from the superblob/code directory. The blob must have |
716 | * been been validated by cs_validate_csblob() before calling |
717 | * this. Use csblob_find_blob() instead. |
718 | * |
719 | * Will also find a "raw" code directory if its stored as well as |
720 | * searching the superblob. |
721 | * |
722 | * Parameters: buffer Pointer to code signature |
723 | * length Length of buffer |
724 | * type type of blob to find |
725 | * magic the magic number for that blob |
726 | * |
727 | * Returns: pointer Success |
728 | * NULL Buffer not found |
729 | */ |
730 | |
731 | const CS_GenericBlob * |
732 | csblob_find_blob_bytes(const uint8_t *addr, size_t length, uint32_t type, uint32_t magic) |
733 | { |
734 | const CS_GenericBlob *blob = (const CS_GenericBlob *)(const void *)addr; |
735 | |
736 | if ((addr + length) < addr) { |
737 | panic("CODE SIGNING: CS Blob length overflow for addr: %p" , addr); |
738 | } |
739 | |
740 | if (ntohl(blob->magic) == CSMAGIC_EMBEDDED_SIGNATURE) { |
741 | const CS_SuperBlob *sb = (const CS_SuperBlob *)blob; |
742 | size_t n, count = ntohl(sb->count); |
743 | |
744 | for (n = 0; n < count; n++) { |
745 | if (ntohl(sb->index[n].type) != type) { |
746 | continue; |
747 | } |
748 | uint32_t offset = ntohl(sb->index[n].offset); |
749 | if (length - sizeof(const CS_GenericBlob) < offset) { |
750 | return NULL; |
751 | } |
752 | blob = (const CS_GenericBlob *)(const void *)(addr + offset); |
753 | if (ntohl(blob->magic) != magic) { |
754 | continue; |
755 | } |
756 | if (((vm_address_t)blob + ntohl(blob->length)) < (vm_address_t)blob) { |
757 | panic("CODE SIGNING: CS Blob length overflow for blob at: %p" , blob); |
758 | } else if (((vm_address_t)blob + ntohl(blob->length)) > (vm_address_t)(addr + length)) { |
759 | continue; |
760 | } |
761 | return blob; |
762 | } |
763 | } else if (type == CSSLOT_CODEDIRECTORY && ntohl(blob->magic) == CSMAGIC_CODEDIRECTORY |
764 | && magic == CSMAGIC_CODEDIRECTORY) { |
765 | if (((vm_address_t)blob + ntohl(blob->length)) < (vm_address_t)blob) { |
766 | panic("CODE SIGNING: CS Blob length overflow for code directory blob at: %p" , blob); |
767 | } else if (((vm_address_t)blob + ntohl(blob->length)) > (vm_address_t)(addr + length)) { |
768 | return NULL; |
769 | } |
770 | return blob; |
771 | } |
772 | return NULL; |
773 | } |
774 | |
775 | |
776 | const CS_GenericBlob * |
777 | csblob_find_blob(struct cs_blob *csblob, uint32_t type, uint32_t magic) |
778 | { |
779 | if ((csblob->csb_flags & CS_VALID) == 0) { |
780 | return NULL; |
781 | } |
782 | return csblob_find_blob_bytes(addr: (const uint8_t *)csblob->csb_mem_kaddr, length: csblob->csb_mem_size, type, magic); |
783 | } |
784 | |
785 | static const uint8_t * |
786 | find_special_slot(const CS_CodeDirectory *cd, size_t slotsize, uint32_t slot) |
787 | { |
788 | /* there is no zero special slot since that is the first code slot */ |
789 | if (ntohl(cd->nSpecialSlots) < slot || slot == 0) { |
790 | return NULL; |
791 | } |
792 | |
793 | return (const uint8_t *)cd + ntohl(cd->hashOffset) - (slotsize * slot); |
794 | } |
795 | |
796 | static uint8_t cshash_zero[CS_HASH_MAX_SIZE] = { 0 }; |
797 | |
798 | static int |
799 | csblob_find_special_slot_blob(struct cs_blob* csblob, uint32_t slot, uint32_t magic, const CS_GenericBlob **out_start, size_t *out_length) |
800 | { |
801 | uint8_t computed_hash[CS_HASH_MAX_SIZE]; |
802 | const CS_GenericBlob *blob; |
803 | const CS_CodeDirectory *code_dir; |
804 | const uint8_t *embedded_hash; |
805 | union cs_hash_union context; |
806 | |
807 | if (out_start) { |
808 | *out_start = NULL; |
809 | } |
810 | if (out_length) { |
811 | *out_length = 0; |
812 | } |
813 | |
814 | if (csblob->csb_hashtype == NULL || csblob->csb_hashtype->cs_digest_size > sizeof(computed_hash)) { |
815 | return EBADEXEC; |
816 | } |
817 | |
818 | code_dir = csblob->csb_cd; |
819 | |
820 | blob = csblob_find_blob_bytes(addr: (const uint8_t *)csblob->csb_mem_kaddr, length: csblob->csb_mem_size, type: slot, magic); |
821 | |
822 | embedded_hash = find_special_slot(cd: code_dir, slotsize: csblob->csb_hashtype->cs_size, slot); |
823 | |
824 | if (embedded_hash == NULL) { |
825 | if (blob) { |
826 | return EBADEXEC; |
827 | } |
828 | return 0; |
829 | } else if (blob == NULL) { |
830 | if (memcmp(s1: embedded_hash, s2: cshash_zero, n: csblob->csb_hashtype->cs_size) != 0) { |
831 | return EBADEXEC; |
832 | } else { |
833 | return 0; |
834 | } |
835 | } |
836 | |
837 | csblob->csb_hashtype->cs_init(&context); |
838 | csblob->csb_hashtype->cs_update(&context, blob, ntohl(blob->length)); |
839 | csblob->csb_hashtype->cs_final(computed_hash, &context); |
840 | |
841 | if (memcmp(s1: computed_hash, s2: embedded_hash, n: csblob->csb_hashtype->cs_size) != 0) { |
842 | return EBADEXEC; |
843 | } |
844 | if (out_start) { |
845 | *out_start = blob; |
846 | } |
847 | if (out_length) { |
848 | *out_length = ntohl(blob->length); |
849 | } |
850 | |
851 | return 0; |
852 | } |
853 | |
854 | int |
855 | csblob_get_entitlements(struct cs_blob *csblob, void **out_start, size_t *out_length) |
856 | { |
857 | uint8_t computed_hash[CS_HASH_MAX_SIZE]; |
858 | const CS_GenericBlob *entitlements; |
859 | const CS_CodeDirectory *code_dir; |
860 | const uint8_t *embedded_hash; |
861 | union cs_hash_union context; |
862 | |
863 | *out_start = NULL; |
864 | *out_length = 0; |
865 | |
866 | if (csblob->csb_hashtype == NULL || csblob->csb_hashtype->cs_digest_size > sizeof(computed_hash)) { |
867 | return EBADEXEC; |
868 | } |
869 | |
870 | code_dir = csblob->csb_cd; |
871 | |
872 | if ((csblob->csb_flags & CS_VALID) == 0) { |
873 | entitlements = NULL; |
874 | } else { |
875 | entitlements = csblob->csb_entitlements_blob; |
876 | } |
877 | embedded_hash = find_special_slot(cd: code_dir, slotsize: csblob->csb_hashtype->cs_size, slot: CSSLOT_ENTITLEMENTS); |
878 | |
879 | if (embedded_hash == NULL) { |
880 | if (entitlements) { |
881 | return EBADEXEC; |
882 | } |
883 | return 0; |
884 | } else if (entitlements == NULL) { |
885 | if (memcmp(s1: embedded_hash, s2: cshash_zero, n: csblob->csb_hashtype->cs_size) != 0) { |
886 | return EBADEXEC; |
887 | } else { |
888 | return 0; |
889 | } |
890 | } |
891 | |
892 | csblob->csb_hashtype->cs_init(&context); |
893 | csblob->csb_hashtype->cs_update(&context, entitlements, ntohl(entitlements->length)); |
894 | csblob->csb_hashtype->cs_final(computed_hash, &context); |
895 | |
896 | if (memcmp(s1: computed_hash, s2: embedded_hash, n: csblob->csb_hashtype->cs_size) != 0) { |
897 | return EBADEXEC; |
898 | } |
899 | |
900 | *out_start = __DECONST(void *, entitlements); |
901 | *out_length = ntohl(entitlements->length); |
902 | |
903 | return 0; |
904 | } |
905 | |
906 | const CS_GenericBlob* |
907 | csblob_get_der_entitlements_unsafe(struct cs_blob * csblob) |
908 | { |
909 | if ((csblob->csb_flags & CS_VALID) == 0) { |
910 | return NULL; |
911 | } |
912 | |
913 | return csblob->csb_der_entitlements_blob; |
914 | } |
915 | |
916 | int |
917 | csblob_get_der_entitlements(struct cs_blob *csblob, const CS_GenericBlob **out_start, size_t *out_length) |
918 | { |
919 | uint8_t computed_hash[CS_HASH_MAX_SIZE]; |
920 | const CS_GenericBlob *der_entitlements; |
921 | const CS_CodeDirectory *code_dir; |
922 | const uint8_t *embedded_hash; |
923 | union cs_hash_union context; |
924 | |
925 | *out_start = NULL; |
926 | *out_length = 0; |
927 | |
928 | if (csblob->csb_hashtype == NULL || csblob->csb_hashtype->cs_digest_size > sizeof(computed_hash)) { |
929 | return EBADEXEC; |
930 | } |
931 | |
932 | code_dir = csblob->csb_cd; |
933 | |
934 | if ((csblob->csb_flags & CS_VALID) == 0) { |
935 | der_entitlements = NULL; |
936 | } else { |
937 | der_entitlements = csblob->csb_der_entitlements_blob; |
938 | } |
939 | embedded_hash = find_special_slot(cd: code_dir, slotsize: csblob->csb_hashtype->cs_size, slot: CSSLOT_DER_ENTITLEMENTS); |
940 | |
941 | if (embedded_hash == NULL) { |
942 | if (der_entitlements) { |
943 | return EBADEXEC; |
944 | } |
945 | return 0; |
946 | } else if (der_entitlements == NULL) { |
947 | if (memcmp(s1: embedded_hash, s2: cshash_zero, n: csblob->csb_hashtype->cs_size) != 0) { |
948 | return EBADEXEC; |
949 | } else { |
950 | return 0; |
951 | } |
952 | } |
953 | |
954 | csblob->csb_hashtype->cs_init(&context); |
955 | csblob->csb_hashtype->cs_update(&context, der_entitlements, ntohl(der_entitlements->length)); |
956 | csblob->csb_hashtype->cs_final(computed_hash, &context); |
957 | |
958 | if (memcmp(s1: computed_hash, s2: embedded_hash, n: csblob->csb_hashtype->cs_size) != 0) { |
959 | return EBADEXEC; |
960 | } |
961 | |
962 | *out_start = der_entitlements; |
963 | *out_length = ntohl(der_entitlements->length); |
964 | |
965 | return 0; |
966 | } |
967 | |
968 | static bool |
969 | ubc_cs_blob_pagewise_allocate( |
970 | __unused vm_size_t size) |
971 | { |
972 | #if CODE_SIGNING_MONITOR |
973 | /* If the monitor isn't enabled, then we don't need to page-align */ |
974 | if (csm_enabled() == false) { |
975 | return false; |
976 | } |
977 | |
978 | /* |
979 | * Small allocations can be maanged by the monitor itself. We only need to allocate |
980 | * page-wise when it is a sufficiently large allocation and the monitor cannot manage |
981 | * it on its own. |
982 | */ |
983 | if (size <= csm_signature_size_limit()) { |
984 | return false; |
985 | } |
986 | |
987 | return true; |
988 | #else |
989 | /* Without a monitor, we never need to page align */ |
990 | return false; |
991 | #endif /* CODE_SIGNING_MONITOR */ |
992 | } |
993 | |
994 | int |
995 | csblob_register_profile_uuid( |
996 | struct cs_blob __unused *csblob, |
997 | const uuid_t __unused profile_uuid, |
998 | void __unused *profile_addr, |
999 | vm_size_t __unused profile_size) |
1000 | { |
1001 | #if CODE_SIGNING_MONITOR |
1002 | /* Profiles only need to be registered for monitor environments */ |
1003 | assert(profile_addr != NULL); |
1004 | assert(profile_size != 0); |
1005 | assert(csblob != NULL); |
1006 | |
1007 | kern_return_t kr = csm_register_provisioning_profile( |
1008 | profile_uuid, |
1009 | profile_addr, profile_size); |
1010 | |
1011 | if ((kr != KERN_SUCCESS) && (kr != KERN_ALREADY_IN_SET)) { |
1012 | return EPERM; |
1013 | } |
1014 | |
1015 | /* Associate the profile with the monitor's signature object */ |
1016 | kr = csm_associate_provisioning_profile( |
1017 | csblob->csb_csm_obj, |
1018 | profile_uuid); |
1019 | |
1020 | if ((kr != KERN_SUCCESS) && (kr != KERN_NOT_SUPPORTED)) { |
1021 | return EPERM; |
1022 | } |
1023 | |
1024 | return 0; |
1025 | #else |
1026 | return 0; |
1027 | #endif /* CODE_SIGNING_MONITOR */ |
1028 | } |
1029 | |
1030 | /* |
1031 | * CODESIGNING |
1032 | * End of routines to navigate code signing data structures in the kernel. |
1033 | */ |
1034 | |
1035 | |
1036 | |
1037 | /* |
1038 | * ubc_info_init |
1039 | * |
1040 | * Allocate and attach an empty ubc_info structure to a vnode |
1041 | * |
1042 | * Parameters: vp Pointer to the vnode |
1043 | * |
1044 | * Returns: 0 Success |
1045 | * vnode_size:ENOMEM Not enough space |
1046 | * vnode_size:??? Other error from vnode_getattr |
1047 | * |
1048 | */ |
1049 | int |
1050 | ubc_info_init(struct vnode *vp) |
1051 | { |
1052 | return ubc_info_init_internal(vp, withfsize: 0, filesize: 0); |
1053 | } |
1054 | |
1055 | |
1056 | /* |
1057 | * ubc_info_init_withsize |
1058 | * |
1059 | * Allocate and attach a sized ubc_info structure to a vnode |
1060 | * |
1061 | * Parameters: vp Pointer to the vnode |
1062 | * filesize The size of the file |
1063 | * |
1064 | * Returns: 0 Success |
1065 | * vnode_size:ENOMEM Not enough space |
1066 | * vnode_size:??? Other error from vnode_getattr |
1067 | */ |
1068 | int |
1069 | ubc_info_init_withsize(struct vnode *vp, off_t filesize) |
1070 | { |
1071 | return ubc_info_init_internal(vp, withfsize: 1, filesize); |
1072 | } |
1073 | |
1074 | |
1075 | /* |
1076 | * ubc_info_init_internal |
1077 | * |
1078 | * Allocate and attach a ubc_info structure to a vnode |
1079 | * |
1080 | * Parameters: vp Pointer to the vnode |
1081 | * withfsize{0,1} Zero if the size should be obtained |
1082 | * from the vnode; otherwise, use filesize |
1083 | * filesize The size of the file, if withfsize == 1 |
1084 | * |
1085 | * Returns: 0 Success |
1086 | * vnode_size:ENOMEM Not enough space |
1087 | * vnode_size:??? Other error from vnode_getattr |
1088 | * |
1089 | * Notes: We call a blocking zalloc(), and the zone was created as an |
1090 | * expandable and collectable zone, so if no memory is available, |
1091 | * it is possible for zalloc() to block indefinitely. zalloc() |
1092 | * may also panic if the zone of zones is exhausted, since it's |
1093 | * NOT expandable. |
1094 | * |
1095 | * We unconditionally call vnode_pager_setup(), even if this is |
1096 | * a reuse of a ubc_info; in that case, we should probably assert |
1097 | * that it does not already have a pager association, but do not. |
1098 | * |
1099 | * Since memory_object_create_named() can only fail from receiving |
1100 | * an invalid pager argument, the explicit check and panic is |
1101 | * merely precautionary. |
1102 | */ |
1103 | static int |
1104 | ubc_info_init_internal(vnode_t vp, int withfsize, off_t filesize) |
1105 | { |
1106 | struct ubc_info *uip; |
1107 | void * ; |
1108 | int error = 0; |
1109 | kern_return_t kret; |
1110 | memory_object_control_t control; |
1111 | |
1112 | uip = vp->v_ubcinfo; |
1113 | |
1114 | /* |
1115 | * If there is not already a ubc_info attached to the vnode, we |
1116 | * attach one; otherwise, we will reuse the one that's there. |
1117 | */ |
1118 | if (uip == UBC_INFO_NULL) { |
1119 | uip = zalloc_flags(ubc_info_zone, Z_WAITOK | Z_ZERO); |
1120 | |
1121 | uip->ui_vnode = vp; |
1122 | uip->ui_flags = UI_INITED; |
1123 | uip->ui_ucred = NOCRED; |
1124 | } |
1125 | assert(uip->ui_flags != UI_NONE); |
1126 | assert(uip->ui_vnode == vp); |
1127 | |
1128 | /* now set this ubc_info in the vnode */ |
1129 | vp->v_ubcinfo = uip; |
1130 | |
1131 | /* |
1132 | * Allocate a pager object for this vnode |
1133 | * |
1134 | * XXX The value of the pager parameter is currently ignored. |
1135 | * XXX Presumably, this API changed to avoid the race between |
1136 | * XXX setting the pager and the UI_HASPAGER flag. |
1137 | */ |
1138 | pager = (void *)vnode_pager_setup(vp, uip->ui_pager); |
1139 | assert(pager); |
1140 | |
1141 | /* |
1142 | * Explicitly set the pager into the ubc_info, after setting the |
1143 | * UI_HASPAGER flag. |
1144 | */ |
1145 | SET(uip->ui_flags, UI_HASPAGER); |
1146 | uip->ui_pager = pager; |
1147 | |
1148 | /* |
1149 | * Note: We can not use VNOP_GETATTR() to get accurate |
1150 | * value of ui_size because this may be an NFS vnode, and |
1151 | * nfs_getattr() can call vinvalbuf(); if this happens, |
1152 | * ubc_info is not set up to deal with that event. |
1153 | * So use bogus size. |
1154 | */ |
1155 | |
1156 | /* |
1157 | * create a vnode - vm_object association |
1158 | * memory_object_create_named() creates a "named" reference on the |
1159 | * memory object we hold this reference as long as the vnode is |
1160 | * "alive." Since memory_object_create_named() took its own reference |
1161 | * on the vnode pager we passed it, we can drop the reference |
1162 | * vnode_pager_setup() returned here. |
1163 | */ |
1164 | kret = memory_object_create_named(pager, |
1165 | size: (memory_object_size_t)uip->ui_size, control: &control); |
1166 | vnode_pager_deallocate(pager); |
1167 | if (kret != KERN_SUCCESS) { |
1168 | panic("ubc_info_init: memory_object_create_named returned %d" , kret); |
1169 | } |
1170 | |
1171 | assert(control); |
1172 | uip->ui_control = control; /* cache the value of the mo control */ |
1173 | SET(uip->ui_flags, UI_HASOBJREF); /* with a named reference */ |
1174 | |
1175 | if (withfsize == 0) { |
1176 | /* initialize the size */ |
1177 | error = vnode_size(vp, &uip->ui_size, vfs_context_current()); |
1178 | if (error) { |
1179 | uip->ui_size = 0; |
1180 | } |
1181 | } else { |
1182 | uip->ui_size = filesize; |
1183 | } |
1184 | vp->v_lflag |= VNAMED_UBC; /* vnode has a named ubc reference */ |
1185 | |
1186 | return error; |
1187 | } |
1188 | |
1189 | |
1190 | /* |
1191 | * ubc_info_free |
1192 | * |
1193 | * Free a ubc_info structure |
1194 | * |
1195 | * Parameters: uip A pointer to the ubc_info to free |
1196 | * |
1197 | * Returns: (void) |
1198 | * |
1199 | * Notes: If there is a credential that has subsequently been associated |
1200 | * with the ubc_info, the reference to the credential is dropped. |
1201 | * |
1202 | * It's actually impossible for a ubc_info.ui_control to take the |
1203 | * value MEMORY_OBJECT_CONTROL_NULL. |
1204 | */ |
1205 | static void |
1206 | ubc_info_free(struct ubc_info *uip) |
1207 | { |
1208 | if (IS_VALID_CRED(uip->ui_ucred)) { |
1209 | kauth_cred_unref(&uip->ui_ucred); |
1210 | } |
1211 | |
1212 | if (uip->ui_control != MEMORY_OBJECT_CONTROL_NULL) { |
1213 | memory_object_control_deallocate(control: uip->ui_control); |
1214 | } |
1215 | |
1216 | cluster_release(uip); |
1217 | ubc_cs_free(uip); |
1218 | |
1219 | zfree(ubc_info_zone, uip); |
1220 | return; |
1221 | } |
1222 | |
1223 | |
1224 | void |
1225 | ubc_info_deallocate(struct ubc_info *uip) |
1226 | { |
1227 | ubc_info_free(uip); |
1228 | } |
1229 | |
1230 | /* |
1231 | * ubc_setsize_ex |
1232 | * |
1233 | * Tell the VM that the the size of the file represented by the vnode has |
1234 | * changed |
1235 | * |
1236 | * Parameters: vp The vp whose backing file size is |
1237 | * being changed |
1238 | * nsize The new size of the backing file |
1239 | * opts Options |
1240 | * |
1241 | * Returns: EINVAL for new size < 0 |
1242 | * ENOENT if no UBC info exists |
1243 | * EAGAIN if UBC_SETSIZE_NO_FS_REENTRY option is set and new_size < old size |
1244 | * Other errors (mapped to errno_t) returned by VM functions |
1245 | * |
1246 | * Notes: This function will indicate success if the new size is the |
1247 | * same or larger than the old size (in this case, the |
1248 | * remainder of the file will require modification or use of |
1249 | * an existing upl to access successfully). |
1250 | * |
1251 | * This function will fail if the new file size is smaller, |
1252 | * and the memory region being invalidated was unable to |
1253 | * actually be invalidated and/or the last page could not be |
1254 | * flushed, if the new size is not aligned to a page |
1255 | * boundary. This is usually indicative of an I/O error. |
1256 | */ |
1257 | errno_t |
1258 | ubc_setsize_ex(struct vnode *vp, off_t nsize, ubc_setsize_opts_t opts) |
1259 | { |
1260 | off_t osize; /* ui_size before change */ |
1261 | off_t lastpg, olastpgend, lastoff; |
1262 | struct ubc_info *uip; |
1263 | memory_object_control_t control; |
1264 | kern_return_t kret = KERN_SUCCESS; |
1265 | |
1266 | if (nsize < (off_t)0) { |
1267 | return EINVAL; |
1268 | } |
1269 | |
1270 | if (!UBCINFOEXISTS(vp)) { |
1271 | return ENOENT; |
1272 | } |
1273 | |
1274 | uip = vp->v_ubcinfo; |
1275 | osize = uip->ui_size; |
1276 | |
1277 | if (ISSET(opts, UBC_SETSIZE_NO_FS_REENTRY) && nsize < osize) { |
1278 | return EAGAIN; |
1279 | } |
1280 | |
1281 | /* |
1282 | * Update the size before flushing the VM |
1283 | */ |
1284 | uip->ui_size = nsize; |
1285 | |
1286 | if (nsize >= osize) { /* Nothing more to do */ |
1287 | if (nsize > osize) { |
1288 | lock_vnode_and_post(vp, NOTE_EXTEND); |
1289 | } |
1290 | |
1291 | return 0; |
1292 | } |
1293 | |
1294 | /* |
1295 | * When the file shrinks, invalidate the pages beyond the |
1296 | * new size. Also get rid of garbage beyond nsize on the |
1297 | * last page. The ui_size already has the nsize, so any |
1298 | * subsequent page-in will zero-fill the tail properly |
1299 | */ |
1300 | lastpg = trunc_page_64(nsize); |
1301 | olastpgend = round_page_64(x: osize); |
1302 | control = uip->ui_control; |
1303 | assert(control); |
1304 | lastoff = (nsize & PAGE_MASK_64); |
1305 | |
1306 | if (lastoff) { |
1307 | upl_t upl; |
1308 | upl_page_info_t *pl; |
1309 | |
1310 | /* |
1311 | * new EOF ends up in the middle of a page |
1312 | * zero the tail of this page if it's currently |
1313 | * present in the cache |
1314 | */ |
1315 | kret = ubc_create_upl_kernel(vp, lastpg, PAGE_SIZE, &upl, &pl, UPL_SET_LITE | UPL_WILL_MODIFY, VM_KERN_MEMORY_FILE); |
1316 | |
1317 | if (kret != KERN_SUCCESS) { |
1318 | panic("ubc_setsize: ubc_create_upl (error = %d)" , kret); |
1319 | } |
1320 | |
1321 | if (upl_valid_page(upl: pl, index: 0)) { |
1322 | cluster_zero(upl, (uint32_t)lastoff, PAGE_SIZE - (uint32_t)lastoff, NULL); |
1323 | } |
1324 | |
1325 | ubc_upl_abort_range(upl, 0, PAGE_SIZE, UPL_ABORT_FREE_ON_EMPTY); |
1326 | |
1327 | lastpg += PAGE_SIZE_64; |
1328 | } |
1329 | if (olastpgend > lastpg) { |
1330 | int flags; |
1331 | |
1332 | if (lastpg == 0) { |
1333 | flags = MEMORY_OBJECT_DATA_FLUSH_ALL; |
1334 | } else { |
1335 | flags = MEMORY_OBJECT_DATA_FLUSH; |
1336 | } |
1337 | /* |
1338 | * invalidate the pages beyond the new EOF page |
1339 | * |
1340 | */ |
1341 | kret = memory_object_lock_request(memory_control: control, |
1342 | offset: (memory_object_offset_t)lastpg, |
1343 | size: (memory_object_size_t)(olastpgend - lastpg), NULL, NULL, |
1344 | MEMORY_OBJECT_RETURN_NONE, flags, VM_PROT_NO_CHANGE); |
1345 | if (kret != KERN_SUCCESS) { |
1346 | printf("ubc_setsize: invalidate failed (error = %d)\n" , kret); |
1347 | } |
1348 | } |
1349 | return mach_to_bsd_errno(mach_err: kret); |
1350 | } |
1351 | |
1352 | // Returns true for success |
1353 | int |
1354 | ubc_setsize(vnode_t vp, off_t nsize) |
1355 | { |
1356 | return ubc_setsize_ex(vp, nsize, opts: 0) == 0; |
1357 | } |
1358 | |
1359 | /* |
1360 | * ubc_getsize |
1361 | * |
1362 | * Get the size of the file assocated with the specified vnode |
1363 | * |
1364 | * Parameters: vp The vnode whose size is of interest |
1365 | * |
1366 | * Returns: 0 There is no ubc_info associated with |
1367 | * this vnode, or the size is zero |
1368 | * !0 The size of the file |
1369 | * |
1370 | * Notes: Using this routine, it is not possible for a caller to |
1371 | * successfully distinguish between a vnode associate with a zero |
1372 | * length file, and a vnode with no associated ubc_info. The |
1373 | * caller therefore needs to not care, or needs to ensure that |
1374 | * they have previously successfully called ubc_info_init() or |
1375 | * ubc_info_init_withsize(). |
1376 | */ |
1377 | off_t |
1378 | ubc_getsize(struct vnode *vp) |
1379 | { |
1380 | /* people depend on the side effect of this working this way |
1381 | * as they call this for directory |
1382 | */ |
1383 | if (!UBCINFOEXISTS(vp)) { |
1384 | return (off_t)0; |
1385 | } |
1386 | return vp->v_ubcinfo->ui_size; |
1387 | } |
1388 | |
1389 | |
1390 | /* |
1391 | * ubc_umount |
1392 | * |
1393 | * Call ubc_msync(vp, 0, EOF, NULL, UBC_PUSHALL) on all the vnodes for this |
1394 | * mount point |
1395 | * |
1396 | * Parameters: mp The mount point |
1397 | * |
1398 | * Returns: 0 Success |
1399 | * |
1400 | * Notes: There is no failure indication for this function. |
1401 | * |
1402 | * This function is used in the unmount path; since it may block |
1403 | * I/O indefinitely, it should not be used in the forced unmount |
1404 | * path, since a device unavailability could also block that |
1405 | * indefinitely. |
1406 | * |
1407 | * Because there is no device ejection interlock on USB, FireWire, |
1408 | * or similar devices, it's possible that an ejection that begins |
1409 | * subsequent to the vnode_iterate() completing, either on one of |
1410 | * those devices, or a network mount for which the server quits |
1411 | * responding, etc., may cause the caller to block indefinitely. |
1412 | */ |
1413 | __private_extern__ int |
1414 | ubc_umount(struct mount *mp) |
1415 | { |
1416 | vnode_iterate(mp, flags: 0, callout: ubc_umcallback, arg: 0); |
1417 | return 0; |
1418 | } |
1419 | |
1420 | |
1421 | /* |
1422 | * ubc_umcallback |
1423 | * |
1424 | * Used by ubc_umount() as an internal implementation detail; see ubc_umount() |
1425 | * and vnode_iterate() for details of implementation. |
1426 | */ |
1427 | static int |
1428 | ubc_umcallback(vnode_t vp, __unused void * args) |
1429 | { |
1430 | if (UBCINFOEXISTS(vp)) { |
1431 | (void) ubc_msync(vp, (off_t)0, ubc_getsize(vp), NULL, UBC_PUSHALL); |
1432 | } |
1433 | return VNODE_RETURNED; |
1434 | } |
1435 | |
1436 | |
1437 | /* |
1438 | * ubc_getcred |
1439 | * |
1440 | * Get the credentials currently active for the ubc_info associated with the |
1441 | * vnode. |
1442 | * |
1443 | * Parameters: vp The vnode whose ubc_info credentials |
1444 | * are to be retrieved |
1445 | * |
1446 | * Returns: !NOCRED The credentials |
1447 | * NOCRED If there is no ubc_info for the vnode, |
1448 | * or if there is one, but it has not had |
1449 | * any credentials associated with it. |
1450 | */ |
1451 | kauth_cred_t |
1452 | ubc_getcred(struct vnode *vp) |
1453 | { |
1454 | if (UBCINFOEXISTS(vp)) { |
1455 | return vp->v_ubcinfo->ui_ucred; |
1456 | } |
1457 | |
1458 | return NOCRED; |
1459 | } |
1460 | |
1461 | |
1462 | /* |
1463 | * ubc_setthreadcred |
1464 | * |
1465 | * If they are not already set, set the credentials of the ubc_info structure |
1466 | * associated with the vnode to those of the supplied thread; otherwise leave |
1467 | * them alone. |
1468 | * |
1469 | * Parameters: vp The vnode whose ubc_info creds are to |
1470 | * be set |
1471 | * p The process whose credentials are to |
1472 | * be used, if not running on an assumed |
1473 | * credential |
1474 | * thread The thread whose credentials are to |
1475 | * be used |
1476 | * |
1477 | * Returns: 1 This vnode has no associated ubc_info |
1478 | * 0 Success |
1479 | * |
1480 | * Notes: This function is generally used only in the following cases: |
1481 | * |
1482 | * o a memory mapped file via the mmap() system call |
1483 | * o a swap store backing file |
1484 | * o subsequent to a successful write via vn_write() |
1485 | * |
1486 | * The information is then used by the NFS client in order to |
1487 | * cons up a wire message in either the page-in or page-out path. |
1488 | * |
1489 | * There are two potential problems with the use of this API: |
1490 | * |
1491 | * o Because the write path only set it on a successful |
1492 | * write, there is a race window between setting the |
1493 | * credential and its use to evict the pages to the |
1494 | * remote file server |
1495 | * |
1496 | * o Because a page-in may occur prior to a write, the |
1497 | * credential may not be set at this time, if the page-in |
1498 | * is not the result of a mapping established via mmap(). |
1499 | * |
1500 | * In both these cases, this will be triggered from the paging |
1501 | * path, which will instead use the credential of the current |
1502 | * process, which in this case is either the dynamic_pager or |
1503 | * the kernel task, both of which utilize "root" credentials. |
1504 | * |
1505 | * This may potentially permit operations to occur which should |
1506 | * be denied, or it may cause to be denied operations which |
1507 | * should be permitted, depending on the configuration of the NFS |
1508 | * server. |
1509 | */ |
1510 | int |
1511 | ubc_setthreadcred(struct vnode *vp, proc_t p, thread_t thread) |
1512 | { |
1513 | #pragma unused(p, thread) |
1514 | assert(p == current_proc()); |
1515 | assert(thread == current_thread()); |
1516 | |
1517 | return ubc_setcred(vp, kauth_cred_get()); |
1518 | } |
1519 | |
1520 | |
1521 | /* |
1522 | * ubc_setcred |
1523 | * |
1524 | * If they are not already set, set the credentials of the ubc_info structure |
1525 | * associated with the vnode to those specified; otherwise leave them |
1526 | * alone. |
1527 | * |
1528 | * Parameters: vp The vnode whose ubc_info creds are to |
1529 | * be set |
1530 | * ucred The credentials to use |
1531 | * |
1532 | * Returns: 0 This vnode has no associated ubc_info |
1533 | * 1 Success |
1534 | * |
1535 | * Notes: The return values for this function are inverted from nearly |
1536 | * all other uses in the kernel. |
1537 | * |
1538 | * See also ubc_setthreadcred(), above. |
1539 | */ |
1540 | int |
1541 | ubc_setcred(struct vnode *vp, kauth_cred_t ucred) |
1542 | { |
1543 | struct ubc_info *uip; |
1544 | |
1545 | /* If there is no ubc_info, deny the operation */ |
1546 | if (!UBCINFOEXISTS(vp)) { |
1547 | return 0; |
1548 | } |
1549 | |
1550 | /* |
1551 | * Check to see if there is already a credential reference in the |
1552 | * ubc_info; if there is not, take one on the supplied credential. |
1553 | */ |
1554 | vnode_lock(vp); |
1555 | uip = vp->v_ubcinfo; |
1556 | if (!IS_VALID_CRED(uip->ui_ucred)) { |
1557 | kauth_cred_ref(cred: ucred); |
1558 | uip->ui_ucred = ucred; |
1559 | } |
1560 | vnode_unlock(vp); |
1561 | |
1562 | return 1; |
1563 | } |
1564 | |
1565 | /* |
1566 | * ubc_getpager |
1567 | * |
1568 | * Get the pager associated with the ubc_info associated with the vnode. |
1569 | * |
1570 | * Parameters: vp The vnode to obtain the pager from |
1571 | * |
1572 | * Returns: !VNODE_PAGER_NULL The memory_object_t for the pager |
1573 | * VNODE_PAGER_NULL There is no ubc_info for this vnode |
1574 | * |
1575 | * Notes: For each vnode that has a ubc_info associated with it, that |
1576 | * ubc_info SHALL have a pager associated with it, so in the |
1577 | * normal case, it's impossible to return VNODE_PAGER_NULL for |
1578 | * a vnode with an associated ubc_info. |
1579 | */ |
1580 | __private_extern__ memory_object_t |
1581 | (struct vnode *vp) |
1582 | { |
1583 | if (UBCINFOEXISTS(vp)) { |
1584 | return vp->v_ubcinfo->ui_pager; |
1585 | } |
1586 | |
1587 | return 0; |
1588 | } |
1589 | |
1590 | |
1591 | /* |
1592 | * ubc_getobject |
1593 | * |
1594 | * Get the memory object control associated with the ubc_info associated with |
1595 | * the vnode |
1596 | * |
1597 | * Parameters: vp The vnode to obtain the memory object |
1598 | * from |
1599 | * flags DEPRECATED |
1600 | * |
1601 | * Returns: !MEMORY_OBJECT_CONTROL_NULL |
1602 | * MEMORY_OBJECT_CONTROL_NULL |
1603 | * |
1604 | * Notes: Historically, if the flags were not "do not reactivate", this |
1605 | * function would look up the memory object using the pager if |
1606 | * it did not exist (this could be the case if the vnode had |
1607 | * been previously reactivated). The flags would also permit a |
1608 | * hold to be requested, which would have created an object |
1609 | * reference, if one had not already existed. This usage is |
1610 | * deprecated, as it would permit a race between finding and |
1611 | * taking the reference vs. a single reference being dropped in |
1612 | * another thread. |
1613 | */ |
1614 | memory_object_control_t |
1615 | ubc_getobject(struct vnode *vp, __unused int flags) |
1616 | { |
1617 | if (UBCINFOEXISTS(vp)) { |
1618 | return vp->v_ubcinfo->ui_control; |
1619 | } |
1620 | |
1621 | return MEMORY_OBJECT_CONTROL_NULL; |
1622 | } |
1623 | |
1624 | /* |
1625 | * ubc_blktooff |
1626 | * |
1627 | * Convert a given block number to a memory backing object (file) offset for a |
1628 | * given vnode |
1629 | * |
1630 | * Parameters: vp The vnode in which the block is located |
1631 | * blkno The block number to convert |
1632 | * |
1633 | * Returns: !-1 The offset into the backing object |
1634 | * -1 There is no ubc_info associated with |
1635 | * the vnode |
1636 | * -1 An error occurred in the underlying VFS |
1637 | * while translating the block to an |
1638 | * offset; the most likely cause is that |
1639 | * the caller specified a block past the |
1640 | * end of the file, but this could also be |
1641 | * any other error from VNOP_BLKTOOFF(). |
1642 | * |
1643 | * Note: Representing the error in band loses some information, but does |
1644 | * not occlude a valid offset, since an off_t of -1 is normally |
1645 | * used to represent EOF. If we had a more reliable constant in |
1646 | * our header files for it (i.e. explicitly cast to an off_t), we |
1647 | * would use it here instead. |
1648 | */ |
1649 | off_t |
1650 | ubc_blktooff(vnode_t vp, daddr64_t blkno) |
1651 | { |
1652 | off_t file_offset = -1; |
1653 | int error; |
1654 | |
1655 | if (UBCINFOEXISTS(vp)) { |
1656 | error = VNOP_BLKTOOFF(vp, blkno, &file_offset); |
1657 | if (error) { |
1658 | file_offset = -1; |
1659 | } |
1660 | } |
1661 | |
1662 | return file_offset; |
1663 | } |
1664 | |
1665 | |
1666 | /* |
1667 | * ubc_offtoblk |
1668 | * |
1669 | * Convert a given offset in a memory backing object into a block number for a |
1670 | * given vnode |
1671 | * |
1672 | * Parameters: vp The vnode in which the offset is |
1673 | * located |
1674 | * offset The offset into the backing object |
1675 | * |
1676 | * Returns: !-1 The returned block number |
1677 | * -1 There is no ubc_info associated with |
1678 | * the vnode |
1679 | * -1 An error occurred in the underlying VFS |
1680 | * while translating the block to an |
1681 | * offset; the most likely cause is that |
1682 | * the caller specified a block past the |
1683 | * end of the file, but this could also be |
1684 | * any other error from VNOP_OFFTOBLK(). |
1685 | * |
1686 | * Note: Representing the error in band loses some information, but does |
1687 | * not occlude a valid block number, since block numbers exceed |
1688 | * the valid range for offsets, due to their relative sizes. If |
1689 | * we had a more reliable constant than -1 in our header files |
1690 | * for it (i.e. explicitly cast to an daddr64_t), we would use it |
1691 | * here instead. |
1692 | */ |
1693 | daddr64_t |
1694 | ubc_offtoblk(vnode_t vp, off_t offset) |
1695 | { |
1696 | daddr64_t blkno = -1; |
1697 | int error = 0; |
1698 | |
1699 | if (UBCINFOEXISTS(vp)) { |
1700 | error = VNOP_OFFTOBLK(vp, offset, &blkno); |
1701 | if (error) { |
1702 | blkno = -1; |
1703 | } |
1704 | } |
1705 | |
1706 | return blkno; |
1707 | } |
1708 | |
1709 | |
1710 | /* |
1711 | * ubc_pages_resident |
1712 | * |
1713 | * Determine whether or not a given vnode has pages resident via the memory |
1714 | * object control associated with the ubc_info associated with the vnode |
1715 | * |
1716 | * Parameters: vp The vnode we want to know about |
1717 | * |
1718 | * Returns: 1 Yes |
1719 | * 0 No |
1720 | */ |
1721 | int |
1722 | ubc_pages_resident(vnode_t vp) |
1723 | { |
1724 | kern_return_t kret; |
1725 | boolean_t has_pages_resident; |
1726 | |
1727 | if (!UBCINFOEXISTS(vp)) { |
1728 | return 0; |
1729 | } |
1730 | |
1731 | /* |
1732 | * The following call may fail if an invalid ui_control is specified, |
1733 | * or if there is no VM object associated with the control object. In |
1734 | * either case, reacting to it as if there were no pages resident will |
1735 | * result in correct behavior. |
1736 | */ |
1737 | kret = memory_object_pages_resident(vp->v_ubcinfo->ui_control, &has_pages_resident); |
1738 | |
1739 | if (kret != KERN_SUCCESS) { |
1740 | return 0; |
1741 | } |
1742 | |
1743 | if (has_pages_resident == TRUE) { |
1744 | return 1; |
1745 | } |
1746 | |
1747 | return 0; |
1748 | } |
1749 | |
1750 | /* |
1751 | * ubc_msync |
1752 | * |
1753 | * Clean and/or invalidate a range in the memory object that backs this vnode |
1754 | * |
1755 | * Parameters: vp The vnode whose associated ubc_info's |
1756 | * associated memory object is to have a |
1757 | * range invalidated within it |
1758 | * beg_off The start of the range, as an offset |
1759 | * end_off The end of the range, as an offset |
1760 | * resid_off The address of an off_t supplied by the |
1761 | * caller; may be set to NULL to ignore |
1762 | * flags See ubc_msync_internal() |
1763 | * |
1764 | * Returns: 0 Success |
1765 | * !0 Failure; an errno is returned |
1766 | * |
1767 | * Implicit Returns: |
1768 | * *resid_off, modified If non-NULL, the contents are ALWAYS |
1769 | * modified; they are initialized to the |
1770 | * beg_off, and in case of an I/O error, |
1771 | * the difference between beg_off and the |
1772 | * current value will reflect what was |
1773 | * able to be written before the error |
1774 | * occurred. If no error is returned, the |
1775 | * value of the resid_off is undefined; do |
1776 | * NOT use it in place of end_off if you |
1777 | * intend to increment from the end of the |
1778 | * last call and call iteratively. |
1779 | * |
1780 | * Notes: see ubc_msync_internal() for more detailed information. |
1781 | * |
1782 | */ |
1783 | errno_t |
1784 | ubc_msync(vnode_t vp, off_t beg_off, off_t end_off, off_t *resid_off, int flags) |
1785 | { |
1786 | int retval; |
1787 | int io_errno = 0; |
1788 | |
1789 | if (resid_off) { |
1790 | *resid_off = beg_off; |
1791 | } |
1792 | |
1793 | retval = ubc_msync_internal(vp, beg_off, end_off, resid_off, flags, &io_errno); |
1794 | |
1795 | if (retval == 0 && io_errno == 0) { |
1796 | return EINVAL; |
1797 | } |
1798 | return io_errno; |
1799 | } |
1800 | |
1801 | |
1802 | /* |
1803 | * ubc_msync_internal |
1804 | * |
1805 | * Clean and/or invalidate a range in the memory object that backs this vnode |
1806 | * |
1807 | * Parameters: vp The vnode whose associated ubc_info's |
1808 | * associated memory object is to have a |
1809 | * range invalidated within it |
1810 | * beg_off The start of the range, as an offset |
1811 | * end_off The end of the range, as an offset |
1812 | * resid_off The address of an off_t supplied by the |
1813 | * caller; may be set to NULL to ignore |
1814 | * flags MUST contain at least one of the flags |
1815 | * UBC_INVALIDATE, UBC_PUSHDIRTY, or |
1816 | * UBC_PUSHALL; if UBC_PUSHDIRTY is used, |
1817 | * UBC_SYNC may also be specified to cause |
1818 | * this function to block until the |
1819 | * operation is complete. The behavior |
1820 | * of UBC_SYNC is otherwise undefined. |
1821 | * io_errno The address of an int to contain the |
1822 | * errno from a failed I/O operation, if |
1823 | * one occurs; may be set to NULL to |
1824 | * ignore |
1825 | * |
1826 | * Returns: 1 Success |
1827 | * 0 Failure |
1828 | * |
1829 | * Implicit Returns: |
1830 | * *resid_off, modified The contents of this offset MAY be |
1831 | * modified; in case of an I/O error, the |
1832 | * difference between beg_off and the |
1833 | * current value will reflect what was |
1834 | * able to be written before the error |
1835 | * occurred. |
1836 | * *io_errno, modified The contents of this offset are set to |
1837 | * an errno, if an error occurs; if the |
1838 | * caller supplies an io_errno parameter, |
1839 | * they should be careful to initialize it |
1840 | * to 0 before calling this function to |
1841 | * enable them to distinguish an error |
1842 | * with a valid *resid_off from an invalid |
1843 | * one, and to avoid potentially falsely |
1844 | * reporting an error, depending on use. |
1845 | * |
1846 | * Notes: If there is no ubc_info associated with the vnode supplied, |
1847 | * this function immediately returns success. |
1848 | * |
1849 | * If the value of end_off is less than or equal to beg_off, this |
1850 | * function immediately returns success; that is, end_off is NOT |
1851 | * inclusive. |
1852 | * |
1853 | * IMPORTANT: one of the flags UBC_INVALIDATE, UBC_PUSHDIRTY, or |
1854 | * UBC_PUSHALL MUST be specified; that is, it is NOT possible to |
1855 | * attempt to block on in-progress I/O by calling this function |
1856 | * with UBC_PUSHDIRTY, and then later call it with just UBC_SYNC |
1857 | * in order to block pending on the I/O already in progress. |
1858 | * |
1859 | * The start offset is truncated to the page boundary and the |
1860 | * size is adjusted to include the last page in the range; that |
1861 | * is, end_off on exactly a page boundary will not change if it |
1862 | * is rounded, and the range of bytes written will be from the |
1863 | * truncate beg_off to the rounded (end_off - 1). |
1864 | */ |
1865 | static int |
1866 | ubc_msync_internal(vnode_t vp, off_t beg_off, off_t end_off, off_t *resid_off, int flags, int *io_errno) |
1867 | { |
1868 | memory_object_size_t tsize; |
1869 | kern_return_t kret; |
1870 | int request_flags = 0; |
1871 | int flush_flags = MEMORY_OBJECT_RETURN_NONE; |
1872 | |
1873 | if (!UBCINFOEXISTS(vp)) { |
1874 | return 0; |
1875 | } |
1876 | if ((flags & (UBC_INVALIDATE | UBC_PUSHDIRTY | UBC_PUSHALL)) == 0) { |
1877 | return 0; |
1878 | } |
1879 | if (end_off <= beg_off) { |
1880 | return 1; |
1881 | } |
1882 | |
1883 | if (flags & UBC_INVALIDATE) { |
1884 | /* |
1885 | * discard the resident pages |
1886 | */ |
1887 | request_flags = (MEMORY_OBJECT_DATA_FLUSH | MEMORY_OBJECT_DATA_NO_CHANGE); |
1888 | } |
1889 | |
1890 | if (flags & UBC_SYNC) { |
1891 | /* |
1892 | * wait for all the I/O to complete before returning |
1893 | */ |
1894 | request_flags |= MEMORY_OBJECT_IO_SYNC; |
1895 | } |
1896 | |
1897 | if (flags & UBC_PUSHDIRTY) { |
1898 | /* |
1899 | * we only return the dirty pages in the range |
1900 | */ |
1901 | flush_flags = MEMORY_OBJECT_RETURN_DIRTY; |
1902 | } |
1903 | |
1904 | if (flags & UBC_PUSHALL) { |
1905 | /* |
1906 | * then return all the interesting pages in the range (both |
1907 | * dirty and precious) to the pager |
1908 | */ |
1909 | flush_flags = MEMORY_OBJECT_RETURN_ALL; |
1910 | } |
1911 | |
1912 | beg_off = trunc_page_64(beg_off); |
1913 | end_off = round_page_64(x: end_off); |
1914 | tsize = (memory_object_size_t)end_off - beg_off; |
1915 | |
1916 | /* flush and/or invalidate pages in the range requested */ |
1917 | kret = memory_object_lock_request(memory_control: vp->v_ubcinfo->ui_control, |
1918 | offset: beg_off, size: tsize, |
1919 | resid_offset: (memory_object_offset_t *)resid_off, |
1920 | io_errno, should_return: flush_flags, flags: request_flags, |
1921 | VM_PROT_NO_CHANGE); |
1922 | |
1923 | return (kret == KERN_SUCCESS) ? 1 : 0; |
1924 | } |
1925 | |
1926 | |
1927 | /* |
1928 | * ubc_map |
1929 | * |
1930 | * Explicitly map a vnode that has an associate ubc_info, and add a reference |
1931 | * to it for the ubc system, if there isn't one already, so it will not be |
1932 | * recycled while it's in use, and set flags on the ubc_info to indicate that |
1933 | * we have done this |
1934 | * |
1935 | * Parameters: vp The vnode to map |
1936 | * flags The mapping flags for the vnode; this |
1937 | * will be a combination of one or more of |
1938 | * PROT_READ, PROT_WRITE, and PROT_EXEC |
1939 | * |
1940 | * Returns: 0 Success |
1941 | * EPERM Permission was denied |
1942 | * |
1943 | * Notes: An I/O reference on the vnode must already be held on entry |
1944 | * |
1945 | * If there is no ubc_info associated with the vnode, this function |
1946 | * will return success. |
1947 | * |
1948 | * If a permission error occurs, this function will return |
1949 | * failure; all other failures will cause this function to return |
1950 | * success. |
1951 | * |
1952 | * IMPORTANT: This is an internal use function, and its symbols |
1953 | * are not exported, hence its error checking is not very robust. |
1954 | * It is primarily used by: |
1955 | * |
1956 | * o mmap(), when mapping a file |
1957 | * o When mapping a shared file (a shared library in the |
1958 | * shared segment region) |
1959 | * o When loading a program image during the exec process |
1960 | * |
1961 | * ...all of these uses ignore the return code, and any fault that |
1962 | * results later because of a failure is handled in the fix-up path |
1963 | * of the fault handler. The interface exists primarily as a |
1964 | * performance hint. |
1965 | * |
1966 | * Given that third party implementation of the type of interfaces |
1967 | * that would use this function, such as alternative executable |
1968 | * formats, etc., are unsupported, this function is not exported |
1969 | * for general use. |
1970 | * |
1971 | * The extra reference is held until the VM system unmaps the |
1972 | * vnode from its own context to maintain a vnode reference in |
1973 | * cases like open()/mmap()/close(), which leave the backing |
1974 | * object referenced by a mapped memory region in a process |
1975 | * address space. |
1976 | */ |
1977 | __private_extern__ int |
1978 | ubc_map(vnode_t vp, int flags) |
1979 | { |
1980 | struct ubc_info *uip; |
1981 | int error = 0; |
1982 | int need_ref = 0; |
1983 | int need_wakeup = 0; |
1984 | |
1985 | if (UBCINFOEXISTS(vp)) { |
1986 | vnode_lock(vp); |
1987 | uip = vp->v_ubcinfo; |
1988 | |
1989 | while (ISSET(uip->ui_flags, UI_MAPBUSY)) { |
1990 | SET(uip->ui_flags, UI_MAPWAITING); |
1991 | (void) msleep(chan: &uip->ui_flags, mtx: &vp->v_lock, |
1992 | PRIBIO, wmesg: "ubc_map" , NULL); |
1993 | } |
1994 | SET(uip->ui_flags, UI_MAPBUSY); |
1995 | vnode_unlock(vp); |
1996 | |
1997 | error = VNOP_MMAP(vp, flags, vfs_context_current()); |
1998 | |
1999 | /* |
2000 | * rdar://problem/22587101 required that we stop propagating |
2001 | * EPERM up the stack. Otherwise, we would have to funnel up |
2002 | * the error at all the call sites for memory_object_map(). |
2003 | * The risk is in having to undo the map/object/entry state at |
2004 | * all these call sites. It would also affect more than just mmap() |
2005 | * e.g. vm_remap(). |
2006 | * |
2007 | * if (error != EPERM) |
2008 | * error = 0; |
2009 | */ |
2010 | |
2011 | error = 0; |
2012 | |
2013 | vnode_lock_spin(vp); |
2014 | |
2015 | if (error == 0) { |
2016 | if (!ISSET(uip->ui_flags, UI_ISMAPPED)) { |
2017 | need_ref = 1; |
2018 | } |
2019 | SET(uip->ui_flags, (UI_WASMAPPED | UI_ISMAPPED)); |
2020 | if (flags & PROT_WRITE) { |
2021 | SET(uip->ui_flags, (UI_WASMAPPEDWRITE | UI_MAPPEDWRITE)); |
2022 | } |
2023 | } |
2024 | CLR(uip->ui_flags, UI_MAPBUSY); |
2025 | |
2026 | if (ISSET(uip->ui_flags, UI_MAPWAITING)) { |
2027 | CLR(uip->ui_flags, UI_MAPWAITING); |
2028 | need_wakeup = 1; |
2029 | } |
2030 | vnode_unlock(vp); |
2031 | |
2032 | if (need_wakeup) { |
2033 | wakeup(chan: &uip->ui_flags); |
2034 | } |
2035 | |
2036 | if (need_ref) { |
2037 | /* |
2038 | * Make sure we get a ref as we can't unwind from here |
2039 | */ |
2040 | if (vnode_ref_ext(vp, 0, VNODE_REF_FORCE)) { |
2041 | panic("%s : VNODE_REF_FORCE failed" , __FUNCTION__); |
2042 | } |
2043 | /* |
2044 | * Vnodes that are on "unreliable" media (like disk |
2045 | * images, network filesystems, 3rd-party filesystems, |
2046 | * and possibly external devices) could see their |
2047 | * contents be changed via the backing store without |
2048 | * triggering copy-on-write, so we can't fully rely |
2049 | * on copy-on-write and might have to resort to |
2050 | * copy-on-read to protect "privileged" processes and |
2051 | * prevent privilege escalation. |
2052 | * |
2053 | * The root filesystem is considered "reliable" because |
2054 | * there's not much point in trying to protect |
2055 | * ourselves from such a vulnerability and the extra |
2056 | * cost of copy-on-read (CPU time and memory pressure) |
2057 | * could result in some serious regressions. |
2058 | */ |
2059 | if (vp->v_mount != NULL && |
2060 | ((vp->v_mount->mnt_flag & MNT_ROOTFS) || |
2061 | vnode_on_reliable_media(vp))) { |
2062 | /* |
2063 | * This vnode is deemed "reliable" so mark |
2064 | * its VM object as "trusted". |
2065 | */ |
2066 | memory_object_mark_trusted(control: uip->ui_control); |
2067 | } else { |
2068 | // printf("BUGGYCOW: %s:%d vp %p \"%s\" in mnt %p \"%s\" is untrusted\n", __FUNCTION__, __LINE__, vp, vp->v_name, vp->v_mount, vp->v_mount->mnt_vnodecovered->v_name); |
2069 | } |
2070 | } |
2071 | } |
2072 | return error; |
2073 | } |
2074 | |
2075 | |
2076 | /* |
2077 | * ubc_destroy_named |
2078 | * |
2079 | * Destroy the named memory object associated with the ubc_info control object |
2080 | * associated with the designated vnode, if there is a ubc_info associated |
2081 | * with the vnode, and a control object is associated with it |
2082 | * |
2083 | * Parameters: vp The designated vnode |
2084 | * |
2085 | * Returns: (void) |
2086 | * |
2087 | * Notes: This function is called on vnode termination for all vnodes, |
2088 | * and must therefore not assume that there is a ubc_info that is |
2089 | * associated with the vnode, nor that there is a control object |
2090 | * associated with the ubc_info. |
2091 | * |
2092 | * If all the conditions necessary are present, this function |
2093 | * calls memory_object_destory(), which will in turn end up |
2094 | * calling ubc_unmap() to release any vnode references that were |
2095 | * established via ubc_map(). |
2096 | * |
2097 | * IMPORTANT: This is an internal use function that is used |
2098 | * exclusively by the internal use function vclean(). |
2099 | */ |
2100 | __private_extern__ void |
2101 | ubc_destroy_named(vnode_t vp, vm_object_destroy_reason_t reason) |
2102 | { |
2103 | memory_object_control_t control; |
2104 | struct ubc_info *uip; |
2105 | kern_return_t kret; |
2106 | |
2107 | if (UBCINFOEXISTS(vp)) { |
2108 | uip = vp->v_ubcinfo; |
2109 | |
2110 | /* Terminate the memory object */ |
2111 | control = ubc_getobject(vp, UBC_HOLDOBJECT); |
2112 | if (control != MEMORY_OBJECT_CONTROL_NULL) { |
2113 | kret = memory_object_destroy(memory_control: control, reason); |
2114 | if (kret != KERN_SUCCESS) { |
2115 | panic("ubc_destroy_named: memory_object_destroy failed" ); |
2116 | } |
2117 | } |
2118 | } |
2119 | } |
2120 | |
2121 | |
2122 | /* |
2123 | * ubc_isinuse |
2124 | * |
2125 | * Determine whether or not a vnode is currently in use by ubc at a level in |
2126 | * excess of the requested busycount |
2127 | * |
2128 | * Parameters: vp The vnode to check |
2129 | * busycount The threshold busy count, used to bias |
2130 | * the count usually already held by the |
2131 | * caller to avoid races |
2132 | * |
2133 | * Returns: 1 The vnode is in use over the threshold |
2134 | * 0 The vnode is not in use over the |
2135 | * threshold |
2136 | * |
2137 | * Notes: Because the vnode is only held locked while actually asking |
2138 | * the use count, this function only represents a snapshot of the |
2139 | * current state of the vnode. If more accurate information is |
2140 | * required, an additional busycount should be held by the caller |
2141 | * and a non-zero busycount used. |
2142 | * |
2143 | * If there is no ubc_info associated with the vnode, this |
2144 | * function will report that the vnode is not in use by ubc. |
2145 | */ |
2146 | int |
2147 | ubc_isinuse(struct vnode *vp, int busycount) |
2148 | { |
2149 | if (!UBCINFOEXISTS(vp)) { |
2150 | return 0; |
2151 | } |
2152 | return ubc_isinuse_locked(vp, busycount, 0); |
2153 | } |
2154 | |
2155 | |
2156 | /* |
2157 | * ubc_isinuse_locked |
2158 | * |
2159 | * Determine whether or not a vnode is currently in use by ubc at a level in |
2160 | * excess of the requested busycount |
2161 | * |
2162 | * Parameters: vp The vnode to check |
2163 | * busycount The threshold busy count, used to bias |
2164 | * the count usually already held by the |
2165 | * caller to avoid races |
2166 | * locked True if the vnode is already locked by |
2167 | * the caller |
2168 | * |
2169 | * Returns: 1 The vnode is in use over the threshold |
2170 | * 0 The vnode is not in use over the |
2171 | * threshold |
2172 | * |
2173 | * Notes: If the vnode is not locked on entry, it is locked while |
2174 | * actually asking the use count. If this is the case, this |
2175 | * function only represents a snapshot of the current state of |
2176 | * the vnode. If more accurate information is required, the |
2177 | * vnode lock should be held by the caller, otherwise an |
2178 | * additional busycount should be held by the caller and a |
2179 | * non-zero busycount used. |
2180 | * |
2181 | * If there is no ubc_info associated with the vnode, this |
2182 | * function will report that the vnode is not in use by ubc. |
2183 | */ |
2184 | int |
2185 | ubc_isinuse_locked(struct vnode *vp, int busycount, int locked) |
2186 | { |
2187 | int retval = 0; |
2188 | |
2189 | |
2190 | if (!locked) { |
2191 | vnode_lock_spin(vp); |
2192 | } |
2193 | |
2194 | if ((vp->v_usecount - vp->v_kusecount) > busycount) { |
2195 | retval = 1; |
2196 | } |
2197 | |
2198 | if (!locked) { |
2199 | vnode_unlock(vp); |
2200 | } |
2201 | return retval; |
2202 | } |
2203 | |
2204 | |
2205 | /* |
2206 | * ubc_unmap |
2207 | * |
2208 | * Reverse the effects of a ubc_map() call for a given vnode |
2209 | * |
2210 | * Parameters: vp vnode to unmap from ubc |
2211 | * |
2212 | * Returns: (void) |
2213 | * |
2214 | * Notes: This is an internal use function used by vnode_pager_unmap(). |
2215 | * It will attempt to obtain a reference on the supplied vnode, |
2216 | * and if it can do so, and there is an associated ubc_info, and |
2217 | * the flags indicate that it was mapped via ubc_map(), then the |
2218 | * flag is cleared, the mapping removed, and the reference taken |
2219 | * by ubc_map() is released. |
2220 | * |
2221 | * IMPORTANT: This MUST only be called by the VM |
2222 | * to prevent race conditions. |
2223 | */ |
2224 | __private_extern__ void |
2225 | ubc_unmap(struct vnode *vp) |
2226 | { |
2227 | struct ubc_info *uip; |
2228 | int need_rele = 0; |
2229 | int need_wakeup = 0; |
2230 | |
2231 | if (vnode_getwithref(vp)) { |
2232 | return; |
2233 | } |
2234 | |
2235 | if (UBCINFOEXISTS(vp)) { |
2236 | bool want_fsevent = false; |
2237 | |
2238 | vnode_lock(vp); |
2239 | uip = vp->v_ubcinfo; |
2240 | |
2241 | while (ISSET(uip->ui_flags, UI_MAPBUSY)) { |
2242 | SET(uip->ui_flags, UI_MAPWAITING); |
2243 | (void) msleep(chan: &uip->ui_flags, mtx: &vp->v_lock, |
2244 | PRIBIO, wmesg: "ubc_unmap" , NULL); |
2245 | } |
2246 | SET(uip->ui_flags, UI_MAPBUSY); |
2247 | |
2248 | if (ISSET(uip->ui_flags, UI_ISMAPPED)) { |
2249 | if (ISSET(uip->ui_flags, UI_MAPPEDWRITE)) { |
2250 | want_fsevent = true; |
2251 | } |
2252 | |
2253 | need_rele = 1; |
2254 | |
2255 | /* |
2256 | * We want to clear the mapped flags after we've called |
2257 | * VNOP_MNOMAP to avoid certain races and allow |
2258 | * VNOP_MNOMAP to call ubc_is_mapped_writable. |
2259 | */ |
2260 | } |
2261 | vnode_unlock(vp); |
2262 | |
2263 | if (need_rele) { |
2264 | vfs_context_t ctx = vfs_context_current(); |
2265 | |
2266 | (void)VNOP_MNOMAP(vp, ctx); |
2267 | |
2268 | #if CONFIG_FSE |
2269 | /* |
2270 | * Why do we want an fsevent here? Normally the |
2271 | * content modified fsevent is posted when a file is |
2272 | * closed and only if it's written to via conventional |
2273 | * means. It's perfectly legal to close a file and |
2274 | * keep your mappings and we don't currently track |
2275 | * whether it was written to via a mapping. |
2276 | * Therefore, we need to post an fsevent here if the |
2277 | * file was mapped writable. This may result in false |
2278 | * events, i.e. we post a notification when nothing |
2279 | * has really changed. |
2280 | */ |
2281 | if (want_fsevent && need_fsevent(FSE_CONTENT_MODIFIED, vp)) { |
2282 | add_fsevent(FSE_CONTENT_MODIFIED_NO_HLINK, ctx, |
2283 | FSE_ARG_VNODE, vp, |
2284 | FSE_ARG_DONE); |
2285 | } |
2286 | #endif |
2287 | |
2288 | vnode_rele(vp); |
2289 | } |
2290 | |
2291 | vnode_lock_spin(vp); |
2292 | |
2293 | if (need_rele) { |
2294 | CLR(uip->ui_flags, UI_ISMAPPED | UI_MAPPEDWRITE); |
2295 | } |
2296 | |
2297 | CLR(uip->ui_flags, UI_MAPBUSY); |
2298 | |
2299 | if (ISSET(uip->ui_flags, UI_MAPWAITING)) { |
2300 | CLR(uip->ui_flags, UI_MAPWAITING); |
2301 | need_wakeup = 1; |
2302 | } |
2303 | vnode_unlock(vp); |
2304 | |
2305 | if (need_wakeup) { |
2306 | wakeup(chan: &uip->ui_flags); |
2307 | } |
2308 | } |
2309 | /* |
2310 | * the drop of the vnode ref will cleanup |
2311 | */ |
2312 | vnode_put(vp); |
2313 | } |
2314 | |
2315 | |
2316 | /* |
2317 | * ubc_page_op |
2318 | * |
2319 | * Manipulate individual page state for a vnode with an associated ubc_info |
2320 | * with an associated memory object control. |
2321 | * |
2322 | * Parameters: vp The vnode backing the page |
2323 | * f_offset A file offset interior to the page |
2324 | * ops The operations to perform, as a bitmap |
2325 | * (see below for more information) |
2326 | * phys_entryp The address of a ppnum_t; may be NULL |
2327 | * to ignore |
2328 | * flagsp A pointer to an int to contain flags; |
2329 | * may be NULL to ignore |
2330 | * |
2331 | * Returns: KERN_SUCCESS Success |
2332 | * KERN_INVALID_ARGUMENT If the memory object control has no VM |
2333 | * object associated |
2334 | * KERN_INVALID_OBJECT If UPL_POP_PHYSICAL and the object is |
2335 | * not physically contiguous |
2336 | * KERN_INVALID_OBJECT If !UPL_POP_PHYSICAL and the object is |
2337 | * physically contiguous |
2338 | * KERN_FAILURE If the page cannot be looked up |
2339 | * |
2340 | * Implicit Returns: |
2341 | * *phys_entryp (modified) If phys_entryp is non-NULL and |
2342 | * UPL_POP_PHYSICAL |
2343 | * *flagsp (modified) If flagsp is non-NULL and there was |
2344 | * !UPL_POP_PHYSICAL and a KERN_SUCCESS |
2345 | * |
2346 | * Notes: For object boundaries, it is considerably more efficient to |
2347 | * ensure that f_offset is in fact on a page boundary, as this |
2348 | * will avoid internal use of the hash table to identify the |
2349 | * page, and would therefore skip a number of early optimizations. |
2350 | * Since this is a page operation anyway, the caller should try |
2351 | * to pass only a page aligned offset because of this. |
2352 | * |
2353 | * *flagsp may be modified even if this function fails. If it is |
2354 | * modified, it will contain the condition of the page before the |
2355 | * requested operation was attempted; these will only include the |
2356 | * bitmap flags, and not the PL_POP_PHYSICAL, UPL_POP_DUMP, |
2357 | * UPL_POP_SET, or UPL_POP_CLR bits. |
2358 | * |
2359 | * The flags field may contain a specific operation, such as |
2360 | * UPL_POP_PHYSICAL or UPL_POP_DUMP: |
2361 | * |
2362 | * o UPL_POP_PHYSICAL Fail if not contiguous; if |
2363 | * *phys_entryp and successful, set |
2364 | * *phys_entryp |
2365 | * o UPL_POP_DUMP Dump the specified page |
2366 | * |
2367 | * Otherwise, it is treated as a bitmap of one or more page |
2368 | * operations to perform on the final memory object; allowable |
2369 | * bit values are: |
2370 | * |
2371 | * o UPL_POP_DIRTY The page is dirty |
2372 | * o UPL_POP_PAGEOUT The page is paged out |
2373 | * o UPL_POP_PRECIOUS The page is precious |
2374 | * o UPL_POP_ABSENT The page is absent |
2375 | * o UPL_POP_BUSY The page is busy |
2376 | * |
2377 | * If the page status is only being queried and not modified, then |
2378 | * not other bits should be specified. However, if it is being |
2379 | * modified, exactly ONE of the following bits should be set: |
2380 | * |
2381 | * o UPL_POP_SET Set the current bitmap bits |
2382 | * o UPL_POP_CLR Clear the current bitmap bits |
2383 | * |
2384 | * Thus to effect a combination of setting an clearing, it may be |
2385 | * necessary to call this function twice. If this is done, the |
2386 | * set should be used before the clear, since clearing may trigger |
2387 | * a wakeup on the destination page, and if the page is backed by |
2388 | * an encrypted swap file, setting will trigger the decryption |
2389 | * needed before the wakeup occurs. |
2390 | */ |
2391 | kern_return_t |
2392 | ubc_page_op( |
2393 | struct vnode *vp, |
2394 | off_t f_offset, |
2395 | int ops, |
2396 | ppnum_t *phys_entryp, |
2397 | int *flagsp) |
2398 | { |
2399 | memory_object_control_t control; |
2400 | |
2401 | control = ubc_getobject(vp, UBC_FLAGS_NONE); |
2402 | if (control == MEMORY_OBJECT_CONTROL_NULL) { |
2403 | return KERN_INVALID_ARGUMENT; |
2404 | } |
2405 | |
2406 | return memory_object_page_op(memory_control: control, |
2407 | offset: (memory_object_offset_t)f_offset, |
2408 | ops, |
2409 | phys_entry: phys_entryp, |
2410 | flags: flagsp); |
2411 | } |
2412 | |
2413 | |
2414 | /* |
2415 | * ubc_range_op |
2416 | * |
2417 | * Manipulate page state for a range of memory for a vnode with an associated |
2418 | * ubc_info with an associated memory object control, when page level state is |
2419 | * not required to be returned from the call (i.e. there are no phys_entryp or |
2420 | * flagsp parameters to this call, and it takes a range which may contain |
2421 | * multiple pages, rather than an offset interior to a single page). |
2422 | * |
2423 | * Parameters: vp The vnode backing the page |
2424 | * f_offset_beg A file offset interior to the start page |
2425 | * f_offset_end A file offset interior to the end page |
2426 | * ops The operations to perform, as a bitmap |
2427 | * (see below for more information) |
2428 | * range The address of an int; may be NULL to |
2429 | * ignore |
2430 | * |
2431 | * Returns: KERN_SUCCESS Success |
2432 | * KERN_INVALID_ARGUMENT If the memory object control has no VM |
2433 | * object associated |
2434 | * KERN_INVALID_OBJECT If the object is physically contiguous |
2435 | * |
2436 | * Implicit Returns: |
2437 | * *range (modified) If range is non-NULL, its contents will |
2438 | * be modified to contain the number of |
2439 | * bytes successfully operated upon. |
2440 | * |
2441 | * Notes: IMPORTANT: This function cannot be used on a range that |
2442 | * consists of physically contiguous pages. |
2443 | * |
2444 | * For object boundaries, it is considerably more efficient to |
2445 | * ensure that f_offset_beg and f_offset_end are in fact on page |
2446 | * boundaries, as this will avoid internal use of the hash table |
2447 | * to identify the page, and would therefore skip a number of |
2448 | * early optimizations. Since this is an operation on a set of |
2449 | * pages anyway, the caller should try to pass only a page aligned |
2450 | * offsets because of this. |
2451 | * |
2452 | * *range will be modified only if this function succeeds. |
2453 | * |
2454 | * The flags field MUST contain a specific operation; allowable |
2455 | * values are: |
2456 | * |
2457 | * o UPL_ROP_ABSENT Returns the extent of the range |
2458 | * presented which is absent, starting |
2459 | * with the start address presented |
2460 | * |
2461 | * o UPL_ROP_PRESENT Returns the extent of the range |
2462 | * presented which is present (resident), |
2463 | * starting with the start address |
2464 | * presented |
2465 | * o UPL_ROP_DUMP Dump the pages which are found in the |
2466 | * target object for the target range. |
2467 | * |
2468 | * IMPORTANT: For UPL_ROP_ABSENT and UPL_ROP_PRESENT; if there are |
2469 | * multiple regions in the range, only the first matching region |
2470 | * is returned. |
2471 | */ |
2472 | kern_return_t |
2473 | ubc_range_op( |
2474 | struct vnode *vp, |
2475 | off_t f_offset_beg, |
2476 | off_t f_offset_end, |
2477 | int ops, |
2478 | int *range) |
2479 | { |
2480 | memory_object_control_t control; |
2481 | |
2482 | control = ubc_getobject(vp, UBC_FLAGS_NONE); |
2483 | if (control == MEMORY_OBJECT_CONTROL_NULL) { |
2484 | return KERN_INVALID_ARGUMENT; |
2485 | } |
2486 | |
2487 | return memory_object_range_op(memory_control: control, |
2488 | offset_beg: (memory_object_offset_t)f_offset_beg, |
2489 | offset_end: (memory_object_offset_t)f_offset_end, |
2490 | ops, |
2491 | range); |
2492 | } |
2493 | |
2494 | |
2495 | /* |
2496 | * ubc_create_upl |
2497 | * |
2498 | * Given a vnode, cause the population of a portion of the vm_object; based on |
2499 | * the nature of the request, the pages returned may contain valid data, or |
2500 | * they may be uninitialized. |
2501 | * |
2502 | * Parameters: vp The vnode from which to create the upl |
2503 | * f_offset The start offset into the backing store |
2504 | * represented by the vnode |
2505 | * bufsize The size of the upl to create |
2506 | * uplp Pointer to the upl_t to receive the |
2507 | * created upl; MUST NOT be NULL |
2508 | * plp Pointer to receive the internal page |
2509 | * list for the created upl; MAY be NULL |
2510 | * to ignore |
2511 | * |
2512 | * Returns: KERN_SUCCESS The requested upl has been created |
2513 | * KERN_INVALID_ARGUMENT The bufsize argument is not an even |
2514 | * multiple of the page size |
2515 | * KERN_INVALID_ARGUMENT There is no ubc_info associated with |
2516 | * the vnode, or there is no memory object |
2517 | * control associated with the ubc_info |
2518 | * memory_object_upl_request:KERN_INVALID_VALUE |
2519 | * The supplied upl_flags argument is |
2520 | * invalid |
2521 | * Implicit Returns: |
2522 | * *uplp (modified) |
2523 | * *plp (modified) If non-NULL, the value of *plp will be |
2524 | * modified to point to the internal page |
2525 | * list; this modification may occur even |
2526 | * if this function is unsuccessful, in |
2527 | * which case the contents may be invalid |
2528 | * |
2529 | * Note: If successful, the returned *uplp MUST subsequently be freed |
2530 | * via a call to ubc_upl_commit(), ubc_upl_commit_range(), |
2531 | * ubc_upl_abort(), or ubc_upl_abort_range(). |
2532 | */ |
2533 | kern_return_t |
2534 | ubc_create_upl_external( |
2535 | struct vnode *vp, |
2536 | off_t f_offset, |
2537 | int bufsize, |
2538 | upl_t *uplp, |
2539 | upl_page_info_t **plp, |
2540 | int uplflags) |
2541 | { |
2542 | return ubc_create_upl_kernel(vp, f_offset, bufsize, uplp, plp, uplflags, vm_tag_bt()); |
2543 | } |
2544 | |
2545 | kern_return_t |
2546 | ubc_create_upl_kernel( |
2547 | struct vnode *vp, |
2548 | off_t f_offset, |
2549 | int bufsize, |
2550 | upl_t *uplp, |
2551 | upl_page_info_t **plp, |
2552 | int uplflags, |
2553 | vm_tag_t tag) |
2554 | { |
2555 | memory_object_control_t control; |
2556 | kern_return_t kr; |
2557 | |
2558 | if (plp != NULL) { |
2559 | *plp = NULL; |
2560 | } |
2561 | *uplp = NULL; |
2562 | |
2563 | if (bufsize & 0xfff) { |
2564 | return KERN_INVALID_ARGUMENT; |
2565 | } |
2566 | |
2567 | if (bufsize > MAX_UPL_SIZE_BYTES) { |
2568 | return KERN_INVALID_ARGUMENT; |
2569 | } |
2570 | |
2571 | if (uplflags & (UPL_UBC_MSYNC | UPL_UBC_PAGEOUT | UPL_UBC_PAGEIN)) { |
2572 | if (uplflags & UPL_UBC_MSYNC) { |
2573 | uplflags &= UPL_RET_ONLY_DIRTY; |
2574 | |
2575 | uplflags |= UPL_COPYOUT_FROM | UPL_CLEAN_IN_PLACE | |
2576 | UPL_SET_INTERNAL | UPL_SET_LITE; |
2577 | } else if (uplflags & UPL_UBC_PAGEOUT) { |
2578 | uplflags &= UPL_RET_ONLY_DIRTY; |
2579 | |
2580 | if (uplflags & UPL_RET_ONLY_DIRTY) { |
2581 | uplflags |= UPL_NOBLOCK; |
2582 | } |
2583 | |
2584 | uplflags |= UPL_FOR_PAGEOUT | UPL_CLEAN_IN_PLACE | |
2585 | UPL_COPYOUT_FROM | UPL_SET_INTERNAL | UPL_SET_LITE; |
2586 | } else { |
2587 | uplflags |= UPL_RET_ONLY_ABSENT | |
2588 | UPL_NO_SYNC | UPL_CLEAN_IN_PLACE | |
2589 | UPL_SET_INTERNAL | UPL_SET_LITE; |
2590 | |
2591 | /* |
2592 | * if the requested size == PAGE_SIZE, we don't want to set |
2593 | * the UPL_NOBLOCK since we may be trying to recover from a |
2594 | * previous partial pagein I/O that occurred because we were low |
2595 | * on memory and bailed early in order to honor the UPL_NOBLOCK... |
2596 | * since we're only asking for a single page, we can block w/o fear |
2597 | * of tying up pages while waiting for more to become available |
2598 | */ |
2599 | if (bufsize > PAGE_SIZE) { |
2600 | uplflags |= UPL_NOBLOCK; |
2601 | } |
2602 | } |
2603 | } else { |
2604 | uplflags &= ~UPL_FOR_PAGEOUT; |
2605 | |
2606 | if (uplflags & UPL_WILL_BE_DUMPED) { |
2607 | uplflags &= ~UPL_WILL_BE_DUMPED; |
2608 | uplflags |= (UPL_NO_SYNC | UPL_SET_INTERNAL); |
2609 | } else { |
2610 | uplflags |= (UPL_NO_SYNC | UPL_CLEAN_IN_PLACE | UPL_SET_INTERNAL); |
2611 | } |
2612 | } |
2613 | control = ubc_getobject(vp, UBC_FLAGS_NONE); |
2614 | if (control == MEMORY_OBJECT_CONTROL_NULL) { |
2615 | return KERN_INVALID_ARGUMENT; |
2616 | } |
2617 | |
2618 | kr = memory_object_upl_request(memory_control: control, offset: f_offset, size: bufsize, upl: uplp, NULL, NULL, cntrl_flags: uplflags, tag); |
2619 | if (kr == KERN_SUCCESS && plp != NULL) { |
2620 | *plp = UPL_GET_INTERNAL_PAGE_LIST(*uplp); |
2621 | } |
2622 | return kr; |
2623 | } |
2624 | |
2625 | |
2626 | /* |
2627 | * ubc_upl_maxbufsize |
2628 | * |
2629 | * Return the maximum bufsize ubc_create_upl( ) will take. |
2630 | * |
2631 | * Parameters: none |
2632 | * |
2633 | * Returns: maximum size buffer (in bytes) ubc_create_upl( ) will take. |
2634 | */ |
2635 | upl_size_t |
2636 | ubc_upl_maxbufsize( |
2637 | void) |
2638 | { |
2639 | return MAX_UPL_SIZE_BYTES; |
2640 | } |
2641 | |
2642 | /* |
2643 | * ubc_upl_map |
2644 | * |
2645 | * Map the page list assocated with the supplied upl into the kernel virtual |
2646 | * address space at the virtual address indicated by the dst_addr argument; |
2647 | * the entire upl is mapped |
2648 | * |
2649 | * Parameters: upl The upl to map |
2650 | * dst_addr The address at which to map the upl |
2651 | * |
2652 | * Returns: KERN_SUCCESS The upl has been mapped |
2653 | * KERN_INVALID_ARGUMENT The upl is UPL_NULL |
2654 | * KERN_FAILURE The upl is already mapped |
2655 | * vm_map_enter:KERN_INVALID_ARGUMENT |
2656 | * A failure code from vm_map_enter() due |
2657 | * to an invalid argument |
2658 | */ |
2659 | kern_return_t |
2660 | ubc_upl_map( |
2661 | upl_t upl, |
2662 | vm_offset_t *dst_addr) |
2663 | { |
2664 | return vm_upl_map(target_task: kernel_map, upl, address: dst_addr); |
2665 | } |
2666 | |
2667 | /* |
2668 | * ubc_upl_map_range:- similar to ubc_upl_map but the focus is on a range |
2669 | * of the UPL. Takes an offset, size, and protection so that only a part |
2670 | * of the UPL can be mapped with the right protections. |
2671 | */ |
2672 | kern_return_t |
2673 | ubc_upl_map_range( |
2674 | upl_t upl, |
2675 | vm_offset_t offset_to_map, |
2676 | vm_size_t size_to_map, |
2677 | vm_prot_t prot_to_map, |
2678 | vm_offset_t *dst_addr) |
2679 | { |
2680 | return vm_upl_map_range(target_task: kernel_map, upl, offset: offset_to_map, size: size_to_map, prot: prot_to_map, address: dst_addr); |
2681 | } |
2682 | |
2683 | |
2684 | /* |
2685 | * ubc_upl_unmap |
2686 | * |
2687 | * Unmap the page list assocated with the supplied upl from the kernel virtual |
2688 | * address space; the entire upl is unmapped. |
2689 | * |
2690 | * Parameters: upl The upl to unmap |
2691 | * |
2692 | * Returns: KERN_SUCCESS The upl has been unmapped |
2693 | * KERN_FAILURE The upl is not currently mapped |
2694 | * KERN_INVALID_ARGUMENT If the upl is UPL_NULL |
2695 | */ |
2696 | kern_return_t |
2697 | ubc_upl_unmap( |
2698 | upl_t upl) |
2699 | { |
2700 | return vm_upl_unmap(target_task: kernel_map, upl); |
2701 | } |
2702 | |
2703 | /* |
2704 | * ubc_upl_unmap_range:- similar to ubc_upl_unmap but the focus is |
2705 | * on part of the UPL that is mapped. The offset and size parameter |
2706 | * specifies what part of the UPL needs to be unmapped. |
2707 | * |
2708 | * Note: Currrently offset & size are unused as we always initiate the unmap from the |
2709 | * very beginning of the UPL's mapping and track the mapped size in the UPL. But we |
2710 | * might want to allow unmapping a UPL in the middle, for example, and we can use the |
2711 | * offset + size parameters for that purpose. |
2712 | */ |
2713 | kern_return_t |
2714 | ubc_upl_unmap_range( |
2715 | upl_t upl, |
2716 | vm_offset_t offset_to_unmap, |
2717 | vm_size_t size_to_unmap) |
2718 | { |
2719 | return vm_upl_unmap_range(target_task: kernel_map, upl, offset: offset_to_unmap, size: size_to_unmap); |
2720 | } |
2721 | |
2722 | |
2723 | /* |
2724 | * ubc_upl_commit |
2725 | * |
2726 | * Commit the contents of the upl to the backing store |
2727 | * |
2728 | * Parameters: upl The upl to commit |
2729 | * |
2730 | * Returns: KERN_SUCCESS The upl has been committed |
2731 | * KERN_INVALID_ARGUMENT The supplied upl was UPL_NULL |
2732 | * KERN_FAILURE The supplied upl does not represent |
2733 | * device memory, and the offset plus the |
2734 | * size would exceed the actual size of |
2735 | * the upl |
2736 | * |
2737 | * Notes: In practice, the only return value for this function should be |
2738 | * KERN_SUCCESS, unless there has been data structure corruption; |
2739 | * since the upl is deallocated regardless of success or failure, |
2740 | * there's really nothing to do about this other than panic. |
2741 | * |
2742 | * IMPORTANT: Use of this function should not be mixed with use of |
2743 | * ubc_upl_commit_range(), due to the unconditional deallocation |
2744 | * by this function. |
2745 | */ |
2746 | kern_return_t |
2747 | ubc_upl_commit( |
2748 | upl_t upl) |
2749 | { |
2750 | upl_page_info_t *pl; |
2751 | kern_return_t kr; |
2752 | |
2753 | pl = UPL_GET_INTERNAL_PAGE_LIST(upl); |
2754 | kr = upl_commit(upl_object: upl, page_list: pl, MAX_UPL_SIZE_BYTES >> PAGE_SHIFT); |
2755 | upl_deallocate(upl); |
2756 | return kr; |
2757 | } |
2758 | |
2759 | |
2760 | /* |
2761 | * ubc_upl_commit |
2762 | * |
2763 | * Commit the contents of the specified range of the upl to the backing store |
2764 | * |
2765 | * Parameters: upl The upl to commit |
2766 | * offset The offset into the upl |
2767 | * size The size of the region to be committed, |
2768 | * starting at the specified offset |
2769 | * flags commit type (see below) |
2770 | * |
2771 | * Returns: KERN_SUCCESS The range has been committed |
2772 | * KERN_INVALID_ARGUMENT The supplied upl was UPL_NULL |
2773 | * KERN_FAILURE The supplied upl does not represent |
2774 | * device memory, and the offset plus the |
2775 | * size would exceed the actual size of |
2776 | * the upl |
2777 | * |
2778 | * Notes: IMPORTANT: If the commit is successful, and the object is now |
2779 | * empty, the upl will be deallocated. Since the caller cannot |
2780 | * check that this is the case, the UPL_COMMIT_FREE_ON_EMPTY flag |
2781 | * should generally only be used when the offset is 0 and the size |
2782 | * is equal to the upl size. |
2783 | * |
2784 | * The flags argument is a bitmap of flags on the rage of pages in |
2785 | * the upl to be committed; allowable flags are: |
2786 | * |
2787 | * o UPL_COMMIT_FREE_ON_EMPTY Free the upl when it is |
2788 | * both empty and has been |
2789 | * successfully committed |
2790 | * o UPL_COMMIT_CLEAR_DIRTY Clear each pages dirty |
2791 | * bit; will prevent a |
2792 | * later pageout |
2793 | * o UPL_COMMIT_SET_DIRTY Set each pages dirty |
2794 | * bit; will cause a later |
2795 | * pageout |
2796 | * o UPL_COMMIT_INACTIVATE Clear each pages |
2797 | * reference bit; the page |
2798 | * will not be accessed |
2799 | * o UPL_COMMIT_ALLOW_ACCESS Unbusy each page; pages |
2800 | * become busy when an |
2801 | * IOMemoryDescriptor is |
2802 | * mapped or redirected, |
2803 | * and we have to wait for |
2804 | * an IOKit driver |
2805 | * |
2806 | * The flag UPL_COMMIT_NOTIFY_EMPTY is used internally, and should |
2807 | * not be specified by the caller. |
2808 | * |
2809 | * The UPL_COMMIT_CLEAR_DIRTY and UPL_COMMIT_SET_DIRTY flags are |
2810 | * mutually exclusive, and should not be combined. |
2811 | */ |
2812 | kern_return_t |
2813 | ubc_upl_commit_range( |
2814 | upl_t upl, |
2815 | upl_offset_t offset, |
2816 | upl_size_t size, |
2817 | int flags) |
2818 | { |
2819 | upl_page_info_t *pl; |
2820 | boolean_t empty; |
2821 | kern_return_t kr; |
2822 | |
2823 | if (flags & UPL_COMMIT_FREE_ON_EMPTY) { |
2824 | flags |= UPL_COMMIT_NOTIFY_EMPTY; |
2825 | } |
2826 | |
2827 | if (flags & UPL_COMMIT_KERNEL_ONLY_FLAGS) { |
2828 | return KERN_INVALID_ARGUMENT; |
2829 | } |
2830 | |
2831 | pl = UPL_GET_INTERNAL_PAGE_LIST(upl); |
2832 | |
2833 | kr = upl_commit_range(upl_object: upl, offset, size, cntrl_flags: flags, |
2834 | page_list: pl, MAX_UPL_SIZE_BYTES >> PAGE_SHIFT, empty: &empty); |
2835 | |
2836 | if ((flags & UPL_COMMIT_FREE_ON_EMPTY) && empty) { |
2837 | upl_deallocate(upl); |
2838 | } |
2839 | |
2840 | return kr; |
2841 | } |
2842 | |
2843 | |
2844 | /* |
2845 | * ubc_upl_abort_range |
2846 | * |
2847 | * Abort the contents of the specified range of the specified upl |
2848 | * |
2849 | * Parameters: upl The upl to abort |
2850 | * offset The offset into the upl |
2851 | * size The size of the region to be aborted, |
2852 | * starting at the specified offset |
2853 | * abort_flags abort type (see below) |
2854 | * |
2855 | * Returns: KERN_SUCCESS The range has been aborted |
2856 | * KERN_INVALID_ARGUMENT The supplied upl was UPL_NULL |
2857 | * KERN_FAILURE The supplied upl does not represent |
2858 | * device memory, and the offset plus the |
2859 | * size would exceed the actual size of |
2860 | * the upl |
2861 | * |
2862 | * Notes: IMPORTANT: If the abort is successful, and the object is now |
2863 | * empty, the upl will be deallocated. Since the caller cannot |
2864 | * check that this is the case, the UPL_ABORT_FREE_ON_EMPTY flag |
2865 | * should generally only be used when the offset is 0 and the size |
2866 | * is equal to the upl size. |
2867 | * |
2868 | * The abort_flags argument is a bitmap of flags on the range of |
2869 | * pages in the upl to be aborted; allowable flags are: |
2870 | * |
2871 | * o UPL_ABORT_FREE_ON_EMPTY Free the upl when it is both |
2872 | * empty and has been successfully |
2873 | * aborted |
2874 | * o UPL_ABORT_RESTART The operation must be restarted |
2875 | * o UPL_ABORT_UNAVAILABLE The pages are unavailable |
2876 | * o UPL_ABORT_ERROR An I/O error occurred |
2877 | * o UPL_ABORT_DUMP_PAGES Just free the pages |
2878 | * o UPL_ABORT_NOTIFY_EMPTY RESERVED |
2879 | * o UPL_ABORT_ALLOW_ACCESS RESERVED |
2880 | * |
2881 | * The UPL_ABORT_NOTIFY_EMPTY is an internal use flag and should |
2882 | * not be specified by the caller. It is intended to fulfill the |
2883 | * same role as UPL_COMMIT_NOTIFY_EMPTY does in the function |
2884 | * ubc_upl_commit_range(), but is never referenced internally. |
2885 | * |
2886 | * The UPL_ABORT_ALLOW_ACCESS is defined, but neither set nor |
2887 | * referenced; do not use it. |
2888 | */ |
2889 | kern_return_t |
2890 | ubc_upl_abort_range( |
2891 | upl_t upl, |
2892 | upl_offset_t offset, |
2893 | upl_size_t size, |
2894 | int abort_flags) |
2895 | { |
2896 | kern_return_t kr; |
2897 | boolean_t empty = FALSE; |
2898 | |
2899 | if (abort_flags & UPL_ABORT_FREE_ON_EMPTY) { |
2900 | abort_flags |= UPL_ABORT_NOTIFY_EMPTY; |
2901 | } |
2902 | |
2903 | kr = upl_abort_range(upl_object: upl, offset, size, abort_cond: abort_flags, empty: &empty); |
2904 | |
2905 | if ((abort_flags & UPL_ABORT_FREE_ON_EMPTY) && empty) { |
2906 | upl_deallocate(upl); |
2907 | } |
2908 | |
2909 | return kr; |
2910 | } |
2911 | |
2912 | |
2913 | /* |
2914 | * ubc_upl_abort |
2915 | * |
2916 | * Abort the contents of the specified upl |
2917 | * |
2918 | * Parameters: upl The upl to abort |
2919 | * abort_type abort type (see below) |
2920 | * |
2921 | * Returns: KERN_SUCCESS The range has been aborted |
2922 | * KERN_INVALID_ARGUMENT The supplied upl was UPL_NULL |
2923 | * KERN_FAILURE The supplied upl does not represent |
2924 | * device memory, and the offset plus the |
2925 | * size would exceed the actual size of |
2926 | * the upl |
2927 | * |
2928 | * Notes: IMPORTANT: If the abort is successful, and the object is now |
2929 | * empty, the upl will be deallocated. Since the caller cannot |
2930 | * check that this is the case, the UPL_ABORT_FREE_ON_EMPTY flag |
2931 | * should generally only be used when the offset is 0 and the size |
2932 | * is equal to the upl size. |
2933 | * |
2934 | * The abort_type is a bitmap of flags on the range of |
2935 | * pages in the upl to be aborted; allowable flags are: |
2936 | * |
2937 | * o UPL_ABORT_FREE_ON_EMPTY Free the upl when it is both |
2938 | * empty and has been successfully |
2939 | * aborted |
2940 | * o UPL_ABORT_RESTART The operation must be restarted |
2941 | * o UPL_ABORT_UNAVAILABLE The pages are unavailable |
2942 | * o UPL_ABORT_ERROR An I/O error occurred |
2943 | * o UPL_ABORT_DUMP_PAGES Just free the pages |
2944 | * o UPL_ABORT_NOTIFY_EMPTY RESERVED |
2945 | * o UPL_ABORT_ALLOW_ACCESS RESERVED |
2946 | * |
2947 | * The UPL_ABORT_NOTIFY_EMPTY is an internal use flag and should |
2948 | * not be specified by the caller. It is intended to fulfill the |
2949 | * same role as UPL_COMMIT_NOTIFY_EMPTY does in the function |
2950 | * ubc_upl_commit_range(), but is never referenced internally. |
2951 | * |
2952 | * The UPL_ABORT_ALLOW_ACCESS is defined, but neither set nor |
2953 | * referenced; do not use it. |
2954 | */ |
2955 | kern_return_t |
2956 | ubc_upl_abort( |
2957 | upl_t upl, |
2958 | int abort_type) |
2959 | { |
2960 | kern_return_t kr; |
2961 | |
2962 | kr = upl_abort(upl_object: upl, abort_cond: abort_type); |
2963 | upl_deallocate(upl); |
2964 | return kr; |
2965 | } |
2966 | |
2967 | |
2968 | /* |
2969 | * ubc_upl_pageinfo |
2970 | * |
2971 | * Retrieve the internal page list for the specified upl |
2972 | * |
2973 | * Parameters: upl The upl to obtain the page list from |
2974 | * |
2975 | * Returns: !NULL The (upl_page_info_t *) for the page |
2976 | * list internal to the upl |
2977 | * NULL Error/no page list associated |
2978 | * |
2979 | * Notes: IMPORTANT: The function is only valid on internal objects |
2980 | * where the list request was made with the UPL_INTERNAL flag. |
2981 | * |
2982 | * This function is a utility helper function, since some callers |
2983 | * may not have direct access to the header defining the macro, |
2984 | * due to abstraction layering constraints. |
2985 | */ |
2986 | upl_page_info_t * |
2987 | ubc_upl_pageinfo( |
2988 | upl_t upl) |
2989 | { |
2990 | return UPL_GET_INTERNAL_PAGE_LIST(upl); |
2991 | } |
2992 | |
2993 | |
2994 | int |
2995 | UBCINFOEXISTS(const struct vnode * vp) |
2996 | { |
2997 | return (vp) && ((vp)->v_type == VREG) && ((vp)->v_ubcinfo != UBC_INFO_NULL); |
2998 | } |
2999 | |
3000 | |
3001 | void |
3002 | ubc_upl_range_needed( |
3003 | upl_t upl, |
3004 | int index, |
3005 | int count) |
3006 | { |
3007 | upl_range_needed(upl, index, count); |
3008 | } |
3009 | |
3010 | boolean_t |
3011 | ubc_is_mapped(const struct vnode *vp, boolean_t *writable) |
3012 | { |
3013 | if (!UBCINFOEXISTS(vp) || !ISSET(vp->v_ubcinfo->ui_flags, UI_ISMAPPED)) { |
3014 | return FALSE; |
3015 | } |
3016 | if (writable) { |
3017 | *writable = ISSET(vp->v_ubcinfo->ui_flags, UI_MAPPEDWRITE); |
3018 | } |
3019 | return TRUE; |
3020 | } |
3021 | |
3022 | boolean_t |
3023 | ubc_is_mapped_writable(const struct vnode *vp) |
3024 | { |
3025 | boolean_t writable; |
3026 | return ubc_is_mapped(vp, writable: &writable) && writable; |
3027 | } |
3028 | |
3029 | boolean_t |
3030 | ubc_was_mapped(const struct vnode *vp, boolean_t *writable) |
3031 | { |
3032 | if (!UBCINFOEXISTS(vp) || !ISSET(vp->v_ubcinfo->ui_flags, UI_WASMAPPED)) { |
3033 | return FALSE; |
3034 | } |
3035 | if (writable) { |
3036 | *writable = ISSET(vp->v_ubcinfo->ui_flags, UI_WASMAPPEDWRITE); |
3037 | } |
3038 | return TRUE; |
3039 | } |
3040 | |
3041 | boolean_t |
3042 | ubc_was_mapped_writable(const struct vnode *vp) |
3043 | { |
3044 | boolean_t writable; |
3045 | return ubc_was_mapped(vp, writable: &writable) && writable; |
3046 | } |
3047 | |
3048 | |
3049 | /* |
3050 | * CODE SIGNING |
3051 | */ |
3052 | static atomic_size_t cs_blob_size = 0; |
3053 | static atomic_uint_fast32_t cs_blob_count = 0; |
3054 | static atomic_size_t cs_blob_size_peak = 0; |
3055 | static atomic_size_t cs_blob_size_max = 0; |
3056 | static atomic_uint_fast32_t cs_blob_count_peak = 0; |
3057 | |
3058 | SYSCTL_UINT(_vm, OID_AUTO, cs_blob_count, CTLFLAG_RD | CTLFLAG_LOCKED, &cs_blob_count, 0, "Current number of code signature blobs" ); |
3059 | SYSCTL_ULONG(_vm, OID_AUTO, cs_blob_size, CTLFLAG_RD | CTLFLAG_LOCKED, &cs_blob_size, "Current size of all code signature blobs" ); |
3060 | SYSCTL_UINT(_vm, OID_AUTO, cs_blob_count_peak, CTLFLAG_RD | CTLFLAG_LOCKED, &cs_blob_count_peak, 0, "Peak number of code signature blobs" ); |
3061 | SYSCTL_ULONG(_vm, OID_AUTO, cs_blob_size_peak, CTLFLAG_RD | CTLFLAG_LOCKED, &cs_blob_size_peak, "Peak size of code signature blobs" ); |
3062 | SYSCTL_ULONG(_vm, OID_AUTO, cs_blob_size_max, CTLFLAG_RD | CTLFLAG_LOCKED, &cs_blob_size_max, "Size of biggest code signature blob" ); |
3063 | |
3064 | /* |
3065 | * Function: csblob_parse_teamid |
3066 | * |
3067 | * Description: This function returns a pointer to the team id |
3068 | * stored within the codedirectory of the csblob. |
3069 | * If the codedirectory predates team-ids, it returns |
3070 | * NULL. |
3071 | * This does not copy the name but returns a pointer to |
3072 | * it within the CD. Subsequently, the CD must be |
3073 | * available when this is used. |
3074 | */ |
3075 | |
3076 | static const char * |
3077 | csblob_parse_teamid(struct cs_blob *csblob) |
3078 | { |
3079 | const CS_CodeDirectory *cd; |
3080 | |
3081 | cd = csblob->csb_cd; |
3082 | |
3083 | if (ntohl(cd->version) < CS_SUPPORTSTEAMID) { |
3084 | return NULL; |
3085 | } |
3086 | |
3087 | if (cd->teamOffset == 0) { |
3088 | return NULL; |
3089 | } |
3090 | |
3091 | const char *name = ((const char *)cd) + ntohl(cd->teamOffset); |
3092 | if (cs_debug > 1) { |
3093 | printf("found team-id %s in cdblob\n" , name); |
3094 | } |
3095 | |
3096 | return name; |
3097 | } |
3098 | |
3099 | kern_return_t |
3100 | ubc_cs_blob_allocate( |
3101 | vm_offset_t *blob_addr_p, |
3102 | vm_size_t *blob_size_p) |
3103 | { |
3104 | kern_return_t kr = KERN_FAILURE; |
3105 | vm_size_t allocation_size = 0; |
3106 | |
3107 | if (!blob_addr_p || !blob_size_p) { |
3108 | return KERN_INVALID_ARGUMENT; |
3109 | } |
3110 | allocation_size = *blob_size_p; |
3111 | |
3112 | if (ubc_cs_blob_pagewise_allocate(size: allocation_size) == true) { |
3113 | /* Round up to page size */ |
3114 | allocation_size = round_page(x: allocation_size); |
3115 | |
3116 | /* Allocate page-wise */ |
3117 | kr = kmem_alloc( |
3118 | map: kernel_map, |
3119 | addrp: blob_addr_p, |
3120 | size: allocation_size, |
3121 | flags: KMA_KOBJECT | KMA_DATA | KMA_ZERO, |
3122 | VM_KERN_MEMORY_SECURITY); |
3123 | } else { |
3124 | *blob_addr_p = (vm_offset_t)kalloc_data_tag( |
3125 | allocation_size, |
3126 | Z_WAITOK | Z_ZERO, |
3127 | VM_KERN_MEMORY_SECURITY); |
3128 | |
3129 | assert(*blob_addr_p != 0); |
3130 | kr = KERN_SUCCESS; |
3131 | } |
3132 | |
3133 | if (kr == KERN_SUCCESS) { |
3134 | *blob_size_p = allocation_size; |
3135 | } |
3136 | |
3137 | return kr; |
3138 | } |
3139 | |
3140 | void |
3141 | ubc_cs_blob_deallocate( |
3142 | vm_offset_t blob_addr, |
3143 | vm_size_t blob_size) |
3144 | { |
3145 | if (ubc_cs_blob_pagewise_allocate(size: blob_size) == true) { |
3146 | kmem_free(map: kernel_map, addr: blob_addr, size: blob_size); |
3147 | } else { |
3148 | kfree_data(blob_addr, blob_size); |
3149 | } |
3150 | } |
3151 | |
3152 | /* |
3153 | * Some codesigned files use a lowest common denominator page size of |
3154 | * 4KiB, but can be used on systems that have a runtime page size of |
3155 | * 16KiB. Since faults will only occur on 16KiB ranges in |
3156 | * cs_validate_range(), we can convert the original Code Directory to |
3157 | * a multi-level scheme where groups of 4 hashes are combined to form |
3158 | * a new hash, which represents 16KiB in the on-disk file. This can |
3159 | * reduce the wired memory requirement for the Code Directory by |
3160 | * 75%. Care must be taken for binaries that use the "fourk" VM pager |
3161 | * for unaligned access, which may still attempt to validate on |
3162 | * non-16KiB multiples for compatibility with 3rd party binaries. |
3163 | */ |
3164 | static boolean_t |
3165 | ubc_cs_supports_multilevel_hash(struct cs_blob *blob __unused) |
3166 | { |
3167 | const CS_CodeDirectory *cd; |
3168 | |
3169 | #if CODE_SIGNING_MONITOR |
3170 | // TODO: <rdar://problem/30954826> |
3171 | if (csm_enabled() == true) { |
3172 | return FALSE; |
3173 | } |
3174 | #endif |
3175 | |
3176 | /* |
3177 | * Only applies to binaries that ship as part of the OS, |
3178 | * primarily the shared cache. |
3179 | */ |
3180 | if (!blob->csb_platform_binary || blob->csb_teamid != NULL) { |
3181 | return FALSE; |
3182 | } |
3183 | |
3184 | /* |
3185 | * If the runtime page size matches the code signing page |
3186 | * size, there is no work to do. |
3187 | */ |
3188 | if (PAGE_SHIFT <= blob->csb_hash_pageshift) { |
3189 | return FALSE; |
3190 | } |
3191 | |
3192 | cd = blob->csb_cd; |
3193 | |
3194 | /* |
3195 | * There must be a valid integral multiple of hashes |
3196 | */ |
3197 | if (ntohl(cd->nCodeSlots) & (PAGE_MASK >> blob->csb_hash_pageshift)) { |
3198 | return FALSE; |
3199 | } |
3200 | |
3201 | /* |
3202 | * Scatter lists must also have ranges that have an integral number of hashes |
3203 | */ |
3204 | if ((ntohl(cd->version) >= CS_SUPPORTSSCATTER) && (ntohl(cd->scatterOffset))) { |
3205 | const SC_Scatter *scatter = (const SC_Scatter*) |
3206 | ((const char*)cd + ntohl(cd->scatterOffset)); |
3207 | /* iterate all scatter structs to make sure they are all aligned */ |
3208 | do { |
3209 | uint32_t sbase = ntohl(scatter->base); |
3210 | uint32_t scount = ntohl(scatter->count); |
3211 | |
3212 | /* last scatter? */ |
3213 | if (scount == 0) { |
3214 | break; |
3215 | } |
3216 | |
3217 | if (sbase & (PAGE_MASK >> blob->csb_hash_pageshift)) { |
3218 | return FALSE; |
3219 | } |
3220 | |
3221 | if (scount & (PAGE_MASK >> blob->csb_hash_pageshift)) { |
3222 | return FALSE; |
3223 | } |
3224 | |
3225 | scatter++; |
3226 | } while (1); |
3227 | } |
3228 | |
3229 | /* Covered range must be a multiple of the new page size */ |
3230 | if (ntohl(cd->codeLimit) & PAGE_MASK) { |
3231 | return FALSE; |
3232 | } |
3233 | |
3234 | /* All checks pass */ |
3235 | return TRUE; |
3236 | } |
3237 | |
3238 | /* |
3239 | * Reconstruct a cs_blob with the code signature fields. This helper function |
3240 | * is useful because a lot of things often change the base address of the code |
3241 | * signature blob, which requires reconstructing some of the other pointers |
3242 | * within. |
3243 | */ |
3244 | static errno_t |
3245 | ubc_cs_blob_reconstruct( |
3246 | struct cs_blob *cs_blob, |
3247 | const vm_address_t signature_addr, |
3248 | const vm_address_t signature_size, |
3249 | const vm_offset_t code_directory_offset) |
3250 | { |
3251 | const CS_CodeDirectory *code_directory = NULL; |
3252 | |
3253 | /* Setup the signature blob address */ |
3254 | cs_blob->csb_mem_kaddr = (void*)signature_addr; |
3255 | cs_blob->csb_mem_size = signature_size; |
3256 | |
3257 | /* Setup the code directory in the blob */ |
3258 | code_directory = (const CS_CodeDirectory*)(signature_addr + code_directory_offset); |
3259 | cs_blob->csb_cd = code_directory; |
3260 | |
3261 | /* Setup the XML entitlements */ |
3262 | cs_blob->csb_entitlements_blob = csblob_find_blob_bytes( |
3263 | addr: (uint8_t*)signature_addr, |
3264 | length: signature_size, |
3265 | type: CSSLOT_ENTITLEMENTS, |
3266 | magic: CSMAGIC_EMBEDDED_ENTITLEMENTS); |
3267 | |
3268 | /* Setup the DER entitlements */ |
3269 | cs_blob->csb_der_entitlements_blob = csblob_find_blob_bytes( |
3270 | addr: (uint8_t*)signature_addr, |
3271 | length: signature_size, |
3272 | type: CSSLOT_DER_ENTITLEMENTS, |
3273 | magic: CSMAGIC_EMBEDDED_DER_ENTITLEMENTS); |
3274 | |
3275 | return 0; |
3276 | } |
3277 | |
3278 | /* |
3279 | * Given a validated cs_blob, we reformat the structure to only include |
3280 | * the blobs which are required by the kernel for our current platform. |
3281 | * This saves significant memory with agile signatures. |
3282 | * |
3283 | * To support rewriting the code directory, potentially through |
3284 | * multilevel hashes, we provide a mechanism to allocate a code directory |
3285 | * of a specified size and zero it out --> caller can fill it in. |
3286 | * |
3287 | * We don't need to perform a lot of overflow checks as the assumption |
3288 | * here is that the cs_blob has already been validated. |
3289 | */ |
3290 | static errno_t |
3291 | ubc_cs_reconstitute_code_signature( |
3292 | const struct cs_blob * const blob, |
3293 | vm_address_t * const ret_mem_kaddr, |
3294 | vm_size_t * const ret_mem_size, |
3295 | vm_size_t code_directory_size, |
3296 | CS_CodeDirectory ** const code_directory |
3297 | ) |
3298 | { |
3299 | vm_address_t new_blob_addr = 0; |
3300 | vm_size_t new_blob_size = 0; |
3301 | vm_size_t new_code_directory_size = 0; |
3302 | const CS_GenericBlob *best_code_directory = NULL; |
3303 | const CS_GenericBlob *first_code_directory = NULL; |
3304 | const CS_GenericBlob *der_entitlements_blob = NULL; |
3305 | const CS_GenericBlob *entitlements_blob = NULL; |
3306 | const CS_GenericBlob *cms_blob = NULL; |
3307 | const CS_GenericBlob *launch_constraint_self = NULL; |
3308 | const CS_GenericBlob *launch_constraint_parent = NULL; |
3309 | const CS_GenericBlob *launch_constraint_responsible = NULL; |
3310 | const CS_GenericBlob *library_constraint = NULL; |
3311 | CS_SuperBlob *superblob = NULL; |
3312 | uint32_t num_blobs = 0; |
3313 | uint32_t blob_index = 0; |
3314 | uint32_t blob_offset = 0; |
3315 | kern_return_t ret; |
3316 | int err; |
3317 | |
3318 | if (!blob) { |
3319 | if (cs_debug > 1) { |
3320 | printf("CODE SIGNING: CS Blob passed in is NULL\n" ); |
3321 | } |
3322 | return EINVAL; |
3323 | } |
3324 | |
3325 | best_code_directory = (const CS_GenericBlob*)blob->csb_cd; |
3326 | if (!best_code_directory) { |
3327 | /* This case can never happen, and it is a sign of bad things */ |
3328 | panic("CODE SIGNING: Validated CS Blob has no code directory" ); |
3329 | } |
3330 | |
3331 | new_code_directory_size = code_directory_size; |
3332 | if (new_code_directory_size == 0) { |
3333 | new_code_directory_size = ntohl(best_code_directory->length); |
3334 | } |
3335 | |
3336 | /* |
3337 | * A code signature can contain multiple code directories, each of which contains hashes |
3338 | * of pages based on a hashing algorithm. The kernel selects which hashing algorithm is |
3339 | * the strongest, and consequently, marks one of these code directories as the best |
3340 | * matched one. More often than not, the best matched one is _not_ the first one. |
3341 | * |
3342 | * However, the CMS blob which cryptographically verifies the code signature is only |
3343 | * signed against the first code directory. Therefore, if the CMS blob is present, we also |
3344 | * need the first code directory to be able to verify it. Given this, we organize the |
3345 | * new cs_blob as following order: |
3346 | * |
3347 | * 1. best code directory |
3348 | * 2. DER encoded entitlements blob (if present) |
3349 | * 3. launch constraint self (if present) |
3350 | * 4. launch constraint parent (if present) |
3351 | * 5. launch constraint responsible (if present) |
3352 | * 6. library constraint (if present) |
3353 | * 7. entitlements blob (if present) |
3354 | * 8. cms blob (if present) |
3355 | * 9. first code directory (if not already the best match, and if cms blob is present) |
3356 | * |
3357 | * This order is chosen deliberately, as later on, we expect to get rid of the CMS blob |
3358 | * and the first code directory once their verification is complete. |
3359 | */ |
3360 | |
3361 | /* Storage for the super blob header */ |
3362 | new_blob_size += sizeof(CS_SuperBlob); |
3363 | |
3364 | /* Guaranteed storage for the best code directory */ |
3365 | new_blob_size += sizeof(CS_BlobIndex); |
3366 | new_blob_size += new_code_directory_size; |
3367 | num_blobs += 1; |
3368 | |
3369 | /* Conditional storage for the DER entitlements blob */ |
3370 | der_entitlements_blob = blob->csb_der_entitlements_blob; |
3371 | if (der_entitlements_blob) { |
3372 | new_blob_size += sizeof(CS_BlobIndex); |
3373 | new_blob_size += ntohl(der_entitlements_blob->length); |
3374 | num_blobs += 1; |
3375 | } |
3376 | |
3377 | /* Conditional storage for the launch constraints self blob */ |
3378 | launch_constraint_self = csblob_find_blob_bytes( |
3379 | addr: (const uint8_t *)blob->csb_mem_kaddr, |
3380 | length: blob->csb_mem_size, |
3381 | type: CSSLOT_LAUNCH_CONSTRAINT_SELF, |
3382 | magic: CSMAGIC_EMBEDDED_LAUNCH_CONSTRAINT); |
3383 | if (launch_constraint_self) { |
3384 | new_blob_size += sizeof(CS_BlobIndex); |
3385 | new_blob_size += ntohl(launch_constraint_self->length); |
3386 | num_blobs += 1; |
3387 | } |
3388 | |
3389 | /* Conditional storage for the launch constraints parent blob */ |
3390 | launch_constraint_parent = csblob_find_blob_bytes( |
3391 | addr: (const uint8_t *)blob->csb_mem_kaddr, |
3392 | length: blob->csb_mem_size, |
3393 | type: CSSLOT_LAUNCH_CONSTRAINT_PARENT, |
3394 | magic: CSMAGIC_EMBEDDED_LAUNCH_CONSTRAINT); |
3395 | if (launch_constraint_parent) { |
3396 | new_blob_size += sizeof(CS_BlobIndex); |
3397 | new_blob_size += ntohl(launch_constraint_parent->length); |
3398 | num_blobs += 1; |
3399 | } |
3400 | |
3401 | /* Conditional storage for the launch constraints responsible blob */ |
3402 | launch_constraint_responsible = csblob_find_blob_bytes( |
3403 | addr: (const uint8_t *)blob->csb_mem_kaddr, |
3404 | length: blob->csb_mem_size, |
3405 | type: CSSLOT_LAUNCH_CONSTRAINT_RESPONSIBLE, |
3406 | magic: CSMAGIC_EMBEDDED_LAUNCH_CONSTRAINT); |
3407 | if (launch_constraint_responsible) { |
3408 | new_blob_size += sizeof(CS_BlobIndex); |
3409 | new_blob_size += ntohl(launch_constraint_responsible->length); |
3410 | num_blobs += 1; |
3411 | } |
3412 | |
3413 | /* Conditional storage for the library constraintsblob */ |
3414 | library_constraint = csblob_find_blob_bytes( |
3415 | addr: (const uint8_t *)blob->csb_mem_kaddr, |
3416 | length: blob->csb_mem_size, |
3417 | type: CSSLOT_LIBRARY_CONSTRAINT, |
3418 | magic: CSMAGIC_EMBEDDED_LAUNCH_CONSTRAINT); |
3419 | if (library_constraint) { |
3420 | new_blob_size += sizeof(CS_BlobIndex); |
3421 | new_blob_size += ntohl(library_constraint->length); |
3422 | num_blobs += 1; |
3423 | } |
3424 | |
3425 | /* Conditional storage for the entitlements blob */ |
3426 | entitlements_blob = blob->csb_entitlements_blob; |
3427 | if (entitlements_blob) { |
3428 | new_blob_size += sizeof(CS_BlobIndex); |
3429 | new_blob_size += ntohl(entitlements_blob->length); |
3430 | num_blobs += 1; |
3431 | } |
3432 | |
3433 | /* Conditional storage for the CMS blob */ |
3434 | cms_blob = csblob_find_blob_bytes(addr: (const uint8_t *)blob->csb_mem_kaddr, length: blob->csb_mem_size, type: CSSLOT_SIGNATURESLOT, magic: CSMAGIC_BLOBWRAPPER); |
3435 | if (cms_blob) { |
3436 | new_blob_size += sizeof(CS_BlobIndex); |
3437 | new_blob_size += ntohl(cms_blob->length); |
3438 | num_blobs += 1; |
3439 | } |
3440 | |
3441 | /* |
3442 | * Conditional storage for the first code directory. |
3443 | * This is only needed if a CMS blob exists and the best code directory isn't already |
3444 | * the first one. It is an error if we find a CMS blob but do not find a first code directory. |
3445 | */ |
3446 | if (cms_blob) { |
3447 | first_code_directory = csblob_find_blob_bytes(addr: (const uint8_t *)blob->csb_mem_kaddr, length: blob->csb_mem_size, type: CSSLOT_CODEDIRECTORY, magic: CSMAGIC_CODEDIRECTORY); |
3448 | if (first_code_directory == best_code_directory) { |
3449 | /* We don't need the first code directory anymore, since the best one is already it */ |
3450 | first_code_directory = NULL; |
3451 | } else if (first_code_directory) { |
3452 | new_blob_size += sizeof(CS_BlobIndex); |
3453 | new_blob_size += ntohl(first_code_directory->length); |
3454 | num_blobs += 1; |
3455 | } else { |
3456 | printf("CODE SIGNING: Invalid CS Blob: found CMS blob but not a first code directory\n" ); |
3457 | return EINVAL; |
3458 | } |
3459 | } |
3460 | |
3461 | /* |
3462 | * The blob size could be rouded up to page size here, so we keep a copy |
3463 | * of the actual superblob length as well. |
3464 | */ |
3465 | vm_size_t new_blob_allocation_size = new_blob_size; |
3466 | ret = ubc_cs_blob_allocate(blob_addr_p: &new_blob_addr, blob_size_p: &new_blob_allocation_size); |
3467 | if (ret != KERN_SUCCESS) { |
3468 | printf("CODE SIGNING: Failed to allocate memory for new code signing blob: %d\n" , ret); |
3469 | return ENOMEM; |
3470 | } |
3471 | |
3472 | /* |
3473 | * Fill out the superblob header and then all the blobs in the order listed |
3474 | * above. |
3475 | */ |
3476 | superblob = (CS_SuperBlob*)new_blob_addr; |
3477 | superblob->magic = htonl(CSMAGIC_EMBEDDED_SIGNATURE); |
3478 | superblob->length = htonl((uint32_t)new_blob_size); |
3479 | superblob->count = htonl(num_blobs); |
3480 | |
3481 | blob_index = 0; |
3482 | blob_offset = sizeof(CS_SuperBlob) + (num_blobs * sizeof(CS_BlobIndex)); |
3483 | |
3484 | /* Best code directory */ |
3485 | superblob->index[blob_index].offset = htonl(blob_offset); |
3486 | if (first_code_directory) { |
3487 | superblob->index[blob_index].type = htonl(CSSLOT_ALTERNATE_CODEDIRECTORIES); |
3488 | } else { |
3489 | superblob->index[blob_index].type = htonl(CSSLOT_CODEDIRECTORY); |
3490 | } |
3491 | |
3492 | if (code_directory_size > 0) { |
3493 | /* We zero out the code directory, as we expect the caller to fill it in */ |
3494 | memset(s: (void*)(new_blob_addr + blob_offset), c: 0, n: new_code_directory_size); |
3495 | } else { |
3496 | memcpy(dst: (void*)(new_blob_addr + blob_offset), src: best_code_directory, n: new_code_directory_size); |
3497 | } |
3498 | |
3499 | if (code_directory) { |
3500 | *code_directory = (CS_CodeDirectory*)(new_blob_addr + blob_offset); |
3501 | } |
3502 | blob_offset += new_code_directory_size; |
3503 | |
3504 | /* DER entitlements blob */ |
3505 | if (der_entitlements_blob) { |
3506 | blob_index += 1; |
3507 | superblob->index[blob_index].offset = htonl(blob_offset); |
3508 | superblob->index[blob_index].type = htonl(CSSLOT_DER_ENTITLEMENTS); |
3509 | |
3510 | memcpy(dst: (void*)(new_blob_addr + blob_offset), src: der_entitlements_blob, ntohl(der_entitlements_blob->length)); |
3511 | blob_offset += ntohl(der_entitlements_blob->length); |
3512 | } |
3513 | |
3514 | /* Launch constraints self blob */ |
3515 | if (launch_constraint_self) { |
3516 | blob_index += 1; |
3517 | superblob->index[blob_index].offset = htonl(blob_offset); |
3518 | superblob->index[blob_index].type = htonl(CSSLOT_LAUNCH_CONSTRAINT_SELF); |
3519 | |
3520 | memcpy( |
3521 | dst: (void*)(new_blob_addr + blob_offset), |
3522 | src: launch_constraint_self, |
3523 | ntohl(launch_constraint_self->length)); |
3524 | |
3525 | blob_offset += ntohl(launch_constraint_self->length); |
3526 | } |
3527 | |
3528 | /* Launch constraints parent blob */ |
3529 | if (launch_constraint_parent) { |
3530 | blob_index += 1; |
3531 | superblob->index[blob_index].offset = htonl(blob_offset); |
3532 | superblob->index[blob_index].type = htonl(CSSLOT_LAUNCH_CONSTRAINT_PARENT); |
3533 | |
3534 | memcpy( |
3535 | dst: (void*)(new_blob_addr + blob_offset), |
3536 | src: launch_constraint_parent, |
3537 | ntohl(launch_constraint_parent->length)); |
3538 | |
3539 | blob_offset += ntohl(launch_constraint_parent->length); |
3540 | } |
3541 | |
3542 | /* Launch constraints responsible blob */ |
3543 | if (launch_constraint_responsible) { |
3544 | blob_index += 1; |
3545 | superblob->index[blob_index].offset = htonl(blob_offset); |
3546 | superblob->index[blob_index].type = htonl(CSSLOT_LAUNCH_CONSTRAINT_RESPONSIBLE); |
3547 | |
3548 | memcpy( |
3549 | dst: (void*)(new_blob_addr + blob_offset), |
3550 | src: launch_constraint_responsible, |
3551 | ntohl(launch_constraint_responsible->length)); |
3552 | |
3553 | blob_offset += ntohl(launch_constraint_responsible->length); |
3554 | } |
3555 | |
3556 | /* library constraints blob */ |
3557 | if (library_constraint) { |
3558 | blob_index += 1; |
3559 | superblob->index[blob_index].offset = htonl(blob_offset); |
3560 | superblob->index[blob_index].type = htonl(CSSLOT_LIBRARY_CONSTRAINT); |
3561 | |
3562 | memcpy( |
3563 | dst: (void*)(new_blob_addr + blob_offset), |
3564 | src: library_constraint, |
3565 | ntohl(library_constraint->length)); |
3566 | |
3567 | blob_offset += ntohl(library_constraint->length); |
3568 | } |
3569 | |
3570 | /* Entitlements blob */ |
3571 | if (entitlements_blob) { |
3572 | blob_index += 1; |
3573 | superblob->index[blob_index].offset = htonl(blob_offset); |
3574 | superblob->index[blob_index].type = htonl(CSSLOT_ENTITLEMENTS); |
3575 | |
3576 | memcpy(dst: (void*)(new_blob_addr + blob_offset), src: entitlements_blob, ntohl(entitlements_blob->length)); |
3577 | blob_offset += ntohl(entitlements_blob->length); |
3578 | } |
3579 | |
3580 | /* CMS blob */ |
3581 | if (cms_blob) { |
3582 | blob_index += 1; |
3583 | superblob->index[blob_index].offset = htonl(blob_offset); |
3584 | superblob->index[blob_index].type = htonl(CSSLOT_SIGNATURESLOT); |
3585 | memcpy(dst: (void*)(new_blob_addr + blob_offset), src: cms_blob, ntohl(cms_blob->length)); |
3586 | blob_offset += ntohl(cms_blob->length); |
3587 | } |
3588 | |
3589 | /* First code directory */ |
3590 | if (first_code_directory) { |
3591 | blob_index += 1; |
3592 | superblob->index[blob_index].offset = htonl(blob_offset); |
3593 | superblob->index[blob_index].type = htonl(CSSLOT_CODEDIRECTORY); |
3594 | memcpy(dst: (void*)(new_blob_addr + blob_offset), src: first_code_directory, ntohl(first_code_directory->length)); |
3595 | blob_offset += ntohl(first_code_directory->length); |
3596 | } |
3597 | |
3598 | /* |
3599 | * We only validate the blob in case we copied in the best code directory. |
3600 | * In case the code directory size we were passed in wasn't 0, we memset the best |
3601 | * code directory to 0 and expect the caller to fill it in. In the same spirit, we |
3602 | * expect the caller to validate the code signature after they fill in the code |
3603 | * directory. |
3604 | */ |
3605 | if (code_directory_size == 0) { |
3606 | const CS_CodeDirectory *validated_code_directory = NULL; |
3607 | const CS_GenericBlob *validated_entitlements_blob = NULL; |
3608 | const CS_GenericBlob *validated_der_entitlements_blob = NULL; |
3609 | |
3610 | ret = cs_validate_csblob( |
3611 | addr: (const uint8_t *)superblob, |
3612 | blob_size: new_blob_size, |
3613 | rcd: &validated_code_directory, |
3614 | rentitlements: &validated_entitlements_blob, |
3615 | rder_entitlements: &validated_der_entitlements_blob); |
3616 | |
3617 | if (ret) { |
3618 | printf("unable to validate reconstituted cs_blob: %d\n" , ret); |
3619 | err = EINVAL; |
3620 | goto fail; |
3621 | } |
3622 | } |
3623 | |
3624 | if (ret_mem_kaddr) { |
3625 | *ret_mem_kaddr = new_blob_addr; |
3626 | } |
3627 | if (ret_mem_size) { |
3628 | *ret_mem_size = new_blob_allocation_size; |
3629 | } |
3630 | |
3631 | return 0; |
3632 | |
3633 | fail: |
3634 | ubc_cs_blob_deallocate(blob_addr: new_blob_addr, blob_size: new_blob_allocation_size); |
3635 | return err; |
3636 | } |
3637 | |
3638 | /* |
3639 | * We use this function to clear out unnecessary bits from the code signature |
3640 | * blob which are no longer needed. We free these bits and give them back to |
3641 | * the kernel. This is needed since reconstitution includes extra data which is |
3642 | * needed only for verification but has no point in keeping afterwards. |
3643 | * |
3644 | * This results in significant memory reduction, especially for 3rd party apps |
3645 | * since we also get rid of the CMS blob. |
3646 | */ |
3647 | static errno_t |
3648 | ubc_cs_reconstitute_code_signature_2nd_stage( |
3649 | struct cs_blob *blob |
3650 | ) |
3651 | { |
3652 | kern_return_t ret = KERN_FAILURE; |
3653 | const CS_GenericBlob *launch_constraint_self = NULL; |
3654 | const CS_GenericBlob *launch_constraint_parent = NULL; |
3655 | const CS_GenericBlob *launch_constraint_responsible = NULL; |
3656 | const CS_GenericBlob *library_constraint = NULL; |
3657 | CS_SuperBlob *superblob = NULL; |
3658 | uint32_t num_blobs = 0; |
3659 | vm_size_t last_needed_blob_offset = 0; |
3660 | vm_offset_t code_directory_offset = 0; |
3661 | |
3662 | /* |
3663 | * Ordering of blobs we need to keep: |
3664 | * 1. Code directory |
3665 | * 2. DER encoded entitlements (if present) |
3666 | * 3. Launch constraints self (if present) |
3667 | * 4. Launch constraints parent (if present) |
3668 | * 5. Launch constraints responsible (if present) |
3669 | * 6. Library constraints (if present) |
3670 | * |
3671 | * We need to clear out the remaining page after these blobs end, and fix up |
3672 | * the superblob for the changes. Things gets a little more complicated for |
3673 | * blobs which may not have been kmem_allocated. For those, we simply just |
3674 | * allocate the new required space and copy into it. |
3675 | */ |
3676 | |
3677 | if (blob == NULL) { |
3678 | printf("NULL blob passed in for 2nd stage reconstitution\n" ); |
3679 | return EINVAL; |
3680 | } |
3681 | assert(blob->csb_reconstituted == true); |
3682 | |
3683 | /* Ensure we're not page-wise allocated when in this function */ |
3684 | assert(ubc_cs_blob_pagewise_allocate(blob->csb_mem_size) == false); |
3685 | |
3686 | if (!blob->csb_cd) { |
3687 | /* This case can never happen, and it is a sign of bad things */ |
3688 | panic("validated cs_blob has no code directory" ); |
3689 | } |
3690 | superblob = (CS_SuperBlob*)blob->csb_mem_kaddr; |
3691 | |
3692 | num_blobs = 1; |
3693 | last_needed_blob_offset = ntohl(superblob->index[0].offset) + ntohl(blob->csb_cd->length); |
3694 | |
3695 | /* Check for DER entitlements */ |
3696 | if (blob->csb_der_entitlements_blob) { |
3697 | num_blobs += 1; |
3698 | last_needed_blob_offset += ntohl(blob->csb_der_entitlements_blob->length); |
3699 | } |
3700 | |
3701 | /* Check for launch constraints self */ |
3702 | launch_constraint_self = csblob_find_blob_bytes( |
3703 | addr: (const uint8_t *)blob->csb_mem_kaddr, |
3704 | length: blob->csb_mem_size, |
3705 | type: CSSLOT_LAUNCH_CONSTRAINT_SELF, |
3706 | magic: CSMAGIC_EMBEDDED_LAUNCH_CONSTRAINT); |
3707 | if (launch_constraint_self) { |
3708 | num_blobs += 1; |
3709 | last_needed_blob_offset += ntohl(launch_constraint_self->length); |
3710 | } |
3711 | |
3712 | /* Check for launch constraints parent */ |
3713 | launch_constraint_parent = csblob_find_blob_bytes( |
3714 | addr: (const uint8_t *)blob->csb_mem_kaddr, |
3715 | length: blob->csb_mem_size, |
3716 | type: CSSLOT_LAUNCH_CONSTRAINT_PARENT, |
3717 | magic: CSMAGIC_EMBEDDED_LAUNCH_CONSTRAINT); |
3718 | if (launch_constraint_parent) { |
3719 | num_blobs += 1; |
3720 | last_needed_blob_offset += ntohl(launch_constraint_parent->length); |
3721 | } |
3722 | |
3723 | /* Check for launch constraints responsible */ |
3724 | launch_constraint_responsible = csblob_find_blob_bytes( |
3725 | addr: (const uint8_t *)blob->csb_mem_kaddr, |
3726 | length: blob->csb_mem_size, |
3727 | type: CSSLOT_LAUNCH_CONSTRAINT_RESPONSIBLE, |
3728 | magic: CSMAGIC_EMBEDDED_LAUNCH_CONSTRAINT); |
3729 | if (launch_constraint_responsible) { |
3730 | num_blobs += 1; |
3731 | last_needed_blob_offset += ntohl(launch_constraint_responsible->length); |
3732 | } |
3733 | |
3734 | /* Check for library constraint */ |
3735 | library_constraint = csblob_find_blob_bytes( |
3736 | addr: (const uint8_t *)blob->csb_mem_kaddr, |
3737 | length: blob->csb_mem_size, |
3738 | type: CSSLOT_LIBRARY_CONSTRAINT, |
3739 | magic: CSMAGIC_EMBEDDED_LAUNCH_CONSTRAINT); |
3740 | if (library_constraint) { |
3741 | num_blobs += 1; |
3742 | last_needed_blob_offset += ntohl(library_constraint->length); |
3743 | } |
3744 | |
3745 | superblob->count = htonl(num_blobs); |
3746 | superblob->length = htonl((uint32_t)last_needed_blob_offset); |
3747 | |
3748 | /* |
3749 | * There is a chance that the code directory is marked within the superblob as an |
3750 | * alternate code directory. This happens when the first code directory isn't the |
3751 | * best one chosen by the kernel, so to be able to access both the first and the best, |
3752 | * we save the best one as an alternate one. Since we're getting rid of the first one |
3753 | * here, we mark the best one as the first one. |
3754 | */ |
3755 | superblob->index[0].type = htonl(CSSLOT_CODEDIRECTORY); |
3756 | |
3757 | vm_address_t new_superblob = 0; |
3758 | vm_size_t new_superblob_size = last_needed_blob_offset; |
3759 | |
3760 | ret = ubc_cs_blob_allocate(blob_addr_p: &new_superblob, blob_size_p: &new_superblob_size); |
3761 | if (ret != KERN_SUCCESS) { |
3762 | printf("unable to allocate memory for 2nd stage reconstitution: %d\n" , ret); |
3763 | return ENOMEM; |
3764 | } |
3765 | assert(new_superblob_size == last_needed_blob_offset); |
3766 | |
3767 | /* Calculate the code directory offset */ |
3768 | code_directory_offset = (vm_offset_t)blob->csb_cd - (vm_offset_t)blob->csb_mem_kaddr; |
3769 | |
3770 | /* Copy in the updated superblob into the new memory */ |
3771 | memcpy(dst: (void*)new_superblob, src: superblob, n: new_superblob_size); |
3772 | |
3773 | /* Free the old code signature and old memory */ |
3774 | ubc_cs_blob_deallocate(blob_addr: (vm_offset_t)blob->csb_mem_kaddr, blob_size: blob->csb_mem_size); |
3775 | |
3776 | /* Reconstruct critical fields in the blob object */ |
3777 | ubc_cs_blob_reconstruct( |
3778 | cs_blob: blob, |
3779 | signature_addr: new_superblob, |
3780 | signature_size: new_superblob_size, |
3781 | code_directory_offset); |
3782 | |
3783 | /* XML entitlements should've been removed */ |
3784 | assert(blob->csb_entitlements_blob == NULL); |
3785 | |
3786 | const CS_CodeDirectory *validated_code_directory = NULL; |
3787 | const CS_GenericBlob *validated_entitlements_blob = NULL; |
3788 | const CS_GenericBlob *validated_der_entitlements_blob = NULL; |
3789 | |
3790 | ret = cs_validate_csblob( |
3791 | addr: (const uint8_t*)blob->csb_mem_kaddr, |
3792 | blob_size: blob->csb_mem_size, |
3793 | rcd: &validated_code_directory, |
3794 | rentitlements: &validated_entitlements_blob, |
3795 | rder_entitlements: &validated_der_entitlements_blob); |
3796 | if (ret) { |
3797 | printf("unable to validate code signature after 2nd stage reconstitution: %d\n" , ret); |
3798 | return EINVAL; |
3799 | } |
3800 | |
3801 | return 0; |
3802 | } |
3803 | |
3804 | static int |
3805 | ubc_cs_convert_to_multilevel_hash(struct cs_blob *blob) |
3806 | { |
3807 | const CS_CodeDirectory *old_cd, *cd; |
3808 | CS_CodeDirectory *new_cd; |
3809 | const CS_GenericBlob *entitlements; |
3810 | const CS_GenericBlob *der_entitlements; |
3811 | vm_offset_t new_blob_addr; |
3812 | vm_size_t new_blob_size; |
3813 | vm_size_t new_cdsize; |
3814 | int error; |
3815 | |
3816 | uint32_t hashes_per_new_hash_shift = (uint32_t)(PAGE_SHIFT - blob->csb_hash_pageshift); |
3817 | |
3818 | if (cs_debug > 1) { |
3819 | printf("CODE SIGNING: Attempting to convert Code Directory for %lu -> %lu page shift\n" , |
3820 | (unsigned long)blob->csb_hash_pageshift, (unsigned long)PAGE_SHIFT); |
3821 | } |
3822 | |
3823 | old_cd = blob->csb_cd; |
3824 | |
3825 | /* Up to the hashes, we can copy all data */ |
3826 | new_cdsize = ntohl(old_cd->hashOffset); |
3827 | new_cdsize += (ntohl(old_cd->nCodeSlots) >> hashes_per_new_hash_shift) * old_cd->hashSize; |
3828 | |
3829 | error = ubc_cs_reconstitute_code_signature(blob, ret_mem_kaddr: &new_blob_addr, ret_mem_size: &new_blob_size, code_directory_size: new_cdsize, code_directory: &new_cd); |
3830 | if (error != 0) { |
3831 | printf("CODE SIGNING: Failed to reconsitute code signature: %d\n" , error); |
3832 | return error; |
3833 | } |
3834 | entitlements = csblob_find_blob_bytes(addr: (uint8_t*)new_blob_addr, length: new_blob_size, type: CSSLOT_ENTITLEMENTS, magic: CSMAGIC_EMBEDDED_ENTITLEMENTS); |
3835 | der_entitlements = csblob_find_blob_bytes(addr: (uint8_t*)new_blob_addr, length: new_blob_size, type: CSSLOT_DER_ENTITLEMENTS, magic: CSMAGIC_EMBEDDED_DER_ENTITLEMENTS); |
3836 | |
3837 | memcpy(dst: new_cd, src: old_cd, ntohl(old_cd->hashOffset)); |
3838 | |
3839 | /* Update fields in the Code Directory structure */ |
3840 | new_cd->length = htonl((uint32_t)new_cdsize); |
3841 | |
3842 | uint32_t nCodeSlots = ntohl(new_cd->nCodeSlots); |
3843 | nCodeSlots >>= hashes_per_new_hash_shift; |
3844 | new_cd->nCodeSlots = htonl(nCodeSlots); |
3845 | |
3846 | new_cd->pageSize = (uint8_t)PAGE_SHIFT; /* Not byte-swapped */ |
3847 | |
3848 | if ((ntohl(new_cd->version) >= CS_SUPPORTSSCATTER) && (ntohl(new_cd->scatterOffset))) { |
3849 | SC_Scatter *scatter = (SC_Scatter*) |
3850 | ((char *)new_cd + ntohl(new_cd->scatterOffset)); |
3851 | /* iterate all scatter structs to scale their counts */ |
3852 | do { |
3853 | uint32_t scount = ntohl(scatter->count); |
3854 | uint32_t sbase = ntohl(scatter->base); |
3855 | |
3856 | /* last scatter? */ |
3857 | if (scount == 0) { |
3858 | break; |
3859 | } |
3860 | |
3861 | scount >>= hashes_per_new_hash_shift; |
3862 | scatter->count = htonl(scount); |
3863 | |
3864 | sbase >>= hashes_per_new_hash_shift; |
3865 | scatter->base = htonl(sbase); |
3866 | |
3867 | scatter++; |
3868 | } while (1); |
3869 | } |
3870 | |
3871 | /* For each group of hashes, hash them together */ |
3872 | const unsigned char *src_base = (const unsigned char *)old_cd + ntohl(old_cd->hashOffset); |
3873 | unsigned char *dst_base = (unsigned char *)new_cd + ntohl(new_cd->hashOffset); |
3874 | |
3875 | uint32_t hash_index; |
3876 | for (hash_index = 0; hash_index < nCodeSlots; hash_index++) { |
3877 | union cs_hash_union mdctx; |
3878 | |
3879 | uint32_t source_hash_len = old_cd->hashSize << hashes_per_new_hash_shift; |
3880 | const unsigned char *src = src_base + hash_index * source_hash_len; |
3881 | unsigned char *dst = dst_base + hash_index * new_cd->hashSize; |
3882 | |
3883 | blob->csb_hashtype->cs_init(&mdctx); |
3884 | blob->csb_hashtype->cs_update(&mdctx, src, source_hash_len); |
3885 | blob->csb_hashtype->cs_final(dst, &mdctx); |
3886 | } |
3887 | |
3888 | error = cs_validate_csblob(addr: (const uint8_t *)new_blob_addr, blob_size: new_blob_size, rcd: &cd, rentitlements: &entitlements, rder_entitlements: &der_entitlements); |
3889 | if (error != 0) { |
3890 | printf("CODE SIGNING: Failed to validate new Code Signing Blob: %d\n" , |
3891 | error); |
3892 | |
3893 | ubc_cs_blob_deallocate(blob_addr: new_blob_addr, blob_size: new_blob_size); |
3894 | return error; |
3895 | } |
3896 | |
3897 | /* New Code Directory is ready for use, swap it out in the blob structure */ |
3898 | ubc_cs_blob_deallocate(blob_addr: (vm_offset_t)blob->csb_mem_kaddr, blob_size: blob->csb_mem_size); |
3899 | |
3900 | blob->csb_mem_size = new_blob_size; |
3901 | blob->csb_mem_kaddr = (void *)new_blob_addr; |
3902 | blob->csb_cd = cd; |
3903 | blob->csb_entitlements_blob = NULL; |
3904 | |
3905 | blob->csb_der_entitlements_blob = der_entitlements; /* may be NULL, not yet validated */ |
3906 | blob->csb_reconstituted = true; |
3907 | |
3908 | /* The blob has some cached attributes of the Code Directory, so update those */ |
3909 | |
3910 | blob->csb_hash_firstlevel_pageshift = blob->csb_hash_pageshift; /* Save the original page size */ |
3911 | |
3912 | blob->csb_hash_pageshift = PAGE_SHIFT; |
3913 | blob->csb_end_offset = ntohl(cd->codeLimit); |
3914 | if ((ntohl(cd->version) >= CS_SUPPORTSSCATTER) && (ntohl(cd->scatterOffset))) { |
3915 | const SC_Scatter *scatter = (const SC_Scatter*) |
3916 | ((const char*)cd + ntohl(cd->scatterOffset)); |
3917 | blob->csb_start_offset = ((off_t)ntohl(scatter->base)) * PAGE_SIZE; |
3918 | } else { |
3919 | blob->csb_start_offset = 0; |
3920 | } |
3921 | |
3922 | return 0; |
3923 | } |
3924 | |
3925 | static void |
3926 | cs_blob_cleanup(struct cs_blob *blob) |
3927 | { |
3928 | if (blob->csb_entitlements != NULL) { |
3929 | amfi->OSEntitlements_invalidate(blob->csb_entitlements); |
3930 | osobject_release(object: blob->csb_entitlements); |
3931 | blob->csb_entitlements = NULL; |
3932 | } |
3933 | |
3934 | #if CODE_SIGNING_MONITOR |
3935 | if (blob->csb_csm_obj != NULL) { |
3936 | /* Unconditionally remove any profiles we may have associated */ |
3937 | csm_disassociate_provisioning_profile(blob->csb_csm_obj); |
3938 | |
3939 | kern_return_t kr = csm_unregister_code_signature(blob->csb_csm_obj); |
3940 | if (kr == KERN_SUCCESS) { |
3941 | /* |
3942 | * If the code signature was monitor managed, the monitor will have freed it |
3943 | * itself in the unregistration call. It means we do not need to free the data |
3944 | * over here. |
3945 | */ |
3946 | if (blob->csb_csm_managed) { |
3947 | blob->csb_mem_kaddr = NULL; |
3948 | blob->csb_mem_size = 0; |
3949 | } |
3950 | } |
3951 | } |
3952 | |
3953 | /* Unconditionally remove references to the monitor */ |
3954 | blob->csb_csm_obj = NULL; |
3955 | blob->csb_csm_managed = false; |
3956 | #endif |
3957 | |
3958 | if (blob->csb_mem_kaddr) { |
3959 | ubc_cs_blob_deallocate(blob_addr: (vm_offset_t)blob->csb_mem_kaddr, blob_size: blob->csb_mem_size); |
3960 | } |
3961 | blob->csb_mem_kaddr = NULL; |
3962 | blob->csb_mem_size = 0; |
3963 | } |
3964 | |
3965 | static void |
3966 | cs_blob_ro_free(struct cs_blob *blob) |
3967 | { |
3968 | struct cs_blob tmp; |
3969 | |
3970 | if (blob != NULL) { |
3971 | /* |
3972 | * cs_blob_cleanup clears fields, so we need to pass it a |
3973 | * mutable copy. |
3974 | */ |
3975 | tmp = *blob; |
3976 | cs_blob_cleanup(blob: &tmp); |
3977 | |
3978 | zfree_ro(ZONE_ID_CS_BLOB, blob); |
3979 | } |
3980 | } |
3981 | |
3982 | /* |
3983 | * Free a cs_blob previously created by cs_blob_create_validated. |
3984 | */ |
3985 | void |
3986 | cs_blob_free( |
3987 | struct cs_blob *blob) |
3988 | { |
3989 | cs_blob_ro_free(blob); |
3990 | } |
3991 | |
3992 | static int |
3993 | cs_blob_init_validated( |
3994 | vm_address_t * const addr, |
3995 | vm_size_t size, |
3996 | struct cs_blob *blob, |
3997 | CS_CodeDirectory const ** const ret_cd) |
3998 | { |
3999 | int error = EINVAL; |
4000 | const CS_CodeDirectory *cd = NULL; |
4001 | const CS_GenericBlob *entitlements = NULL; |
4002 | const CS_GenericBlob *der_entitlements = NULL; |
4003 | union cs_hash_union mdctx; |
4004 | size_t length; |
4005 | |
4006 | bzero(s: blob, n: sizeof(*blob)); |
4007 | |
4008 | /* fill in the new blob */ |
4009 | blob->csb_mem_size = size; |
4010 | blob->csb_mem_offset = 0; |
4011 | blob->csb_mem_kaddr = (void *)*addr; |
4012 | blob->csb_flags = 0; |
4013 | blob->csb_signer_type = CS_SIGNER_TYPE_UNKNOWN; |
4014 | blob->csb_platform_binary = 0; |
4015 | blob->csb_platform_path = 0; |
4016 | blob->csb_teamid = NULL; |
4017 | #if CONFIG_SUPPLEMENTAL_SIGNATURES |
4018 | blob->csb_supplement_teamid = NULL; |
4019 | #endif |
4020 | blob->csb_entitlements_blob = NULL; |
4021 | blob->csb_der_entitlements_blob = NULL; |
4022 | blob->csb_entitlements = NULL; |
4023 | #if CODE_SIGNING_MONITOR |
4024 | blob->csb_csm_obj = NULL; |
4025 | blob->csb_csm_managed = false; |
4026 | #endif |
4027 | blob->csb_reconstituted = false; |
4028 | blob->csb_validation_category = CS_VALIDATION_CATEGORY_INVALID; |
4029 | |
4030 | /* Transfer ownership. Even on error, this function will deallocate */ |
4031 | *addr = 0; |
4032 | |
4033 | /* |
4034 | * Validate the blob's contents |
4035 | */ |
4036 | length = (size_t) size; |
4037 | error = cs_validate_csblob(addr: (const uint8_t *)blob->csb_mem_kaddr, |
4038 | blob_size: length, rcd: &cd, rentitlements: &entitlements, rder_entitlements: &der_entitlements); |
4039 | if (error) { |
4040 | if (cs_debug) { |
4041 | printf("CODESIGNING: csblob invalid: %d\n" , error); |
4042 | } |
4043 | /* |
4044 | * The vnode checker can't make the rest of this function |
4045 | * succeed if csblob validation failed, so bail */ |
4046 | goto out; |
4047 | } else { |
4048 | const unsigned char *md_base; |
4049 | uint8_t hash[CS_HASH_MAX_SIZE]; |
4050 | int md_size; |
4051 | vm_offset_t hash_pagemask; |
4052 | |
4053 | blob->csb_cd = cd; |
4054 | blob->csb_entitlements_blob = entitlements; /* may be NULL, not yet validated */ |
4055 | blob->csb_der_entitlements_blob = der_entitlements; /* may be NULL, not yet validated */ |
4056 | blob->csb_hashtype = cs_find_md(type: cd->hashType); |
4057 | if (blob->csb_hashtype == NULL || blob->csb_hashtype->cs_digest_size > sizeof(hash)) { |
4058 | panic("validated CodeDirectory but unsupported type" ); |
4059 | } |
4060 | |
4061 | blob->csb_hash_pageshift = cd->pageSize; |
4062 | hash_pagemask = (1U << cd->pageSize) - 1; |
4063 | blob->csb_hash_firstlevel_pageshift = 0; |
4064 | blob->csb_flags = (ntohl(cd->flags) & CS_ALLOWED_MACHO) | CS_VALID; |
4065 | blob->csb_end_offset = (((vm_offset_t)ntohl(cd->codeLimit) + hash_pagemask) & ~hash_pagemask); |
4066 | if ((ntohl(cd->version) >= CS_SUPPORTSSCATTER) && (ntohl(cd->scatterOffset))) { |
4067 | const SC_Scatter *scatter = (const SC_Scatter*) |
4068 | ((const char*)cd + ntohl(cd->scatterOffset)); |
4069 | blob->csb_start_offset = ((off_t)ntohl(scatter->base)) * (1U << blob->csb_hash_pageshift); |
4070 | } else { |
4071 | blob->csb_start_offset = 0; |
4072 | } |
4073 | /* compute the blob's cdhash */ |
4074 | md_base = (const unsigned char *) cd; |
4075 | md_size = ntohl(cd->length); |
4076 | |
4077 | blob->csb_hashtype->cs_init(&mdctx); |
4078 | blob->csb_hashtype->cs_update(&mdctx, md_base, md_size); |
4079 | blob->csb_hashtype->cs_final(hash, &mdctx); |
4080 | |
4081 | memcpy(dst: blob->csb_cdhash, src: hash, n: CS_CDHASH_LEN); |
4082 | |
4083 | #if CONFIG_SUPPLEMENTAL_SIGNATURES |
4084 | blob->csb_linkage_hashtype = NULL; |
4085 | if (ntohl(cd->version) >= CS_SUPPORTSLINKAGE && cd->linkageHashType != 0 && |
4086 | ntohl(cd->linkageSize) >= CS_CDHASH_LEN) { |
4087 | blob->csb_linkage_hashtype = cs_find_md(type: cd->linkageHashType); |
4088 | |
4089 | if (blob->csb_linkage_hashtype != NULL) { |
4090 | memcpy(dst: blob->csb_linkage, src: (uint8_t const*)cd + ntohl(cd->linkageOffset), |
4091 | n: CS_CDHASH_LEN); |
4092 | } |
4093 | } |
4094 | #endif |
4095 | } |
4096 | |
4097 | error = 0; |
4098 | |
4099 | out: |
4100 | if (error != 0) { |
4101 | cs_blob_cleanup(blob); |
4102 | blob = NULL; |
4103 | cd = NULL; |
4104 | } |
4105 | |
4106 | if (ret_cd != NULL) { |
4107 | *ret_cd = cd; |
4108 | } |
4109 | |
4110 | return error; |
4111 | } |
4112 | |
4113 | /* |
4114 | * Validate the code signature blob, create a struct cs_blob wrapper |
4115 | * and return it together with a pointer to the chosen code directory |
4116 | * and entitlements blob. |
4117 | * |
4118 | * Note that this takes ownership of the memory as addr, mainly because |
4119 | * this function can actually replace the passed in blob with another |
4120 | * one, e.g. when performing multilevel hashing optimization. |
4121 | */ |
4122 | int |
4123 | cs_blob_create_validated( |
4124 | vm_address_t * const addr, |
4125 | vm_size_t size, |
4126 | struct cs_blob ** const ret_blob, |
4127 | CS_CodeDirectory const ** const ret_cd) |
4128 | { |
4129 | struct cs_blob blob = {}; |
4130 | struct cs_blob *ro_blob; |
4131 | int error; |
4132 | |
4133 | if (ret_blob) { |
4134 | *ret_blob = NULL; |
4135 | } |
4136 | |
4137 | if ((error = cs_blob_init_validated(addr, size, blob: &blob, ret_cd)) != 0) { |
4138 | return error; |
4139 | } |
4140 | |
4141 | if (ret_blob != NULL) { |
4142 | ro_blob = zalloc_ro(ZONE_ID_CS_BLOB, Z_WAITOK | Z_NOFAIL); |
4143 | zalloc_ro_update_elem(ZONE_ID_CS_BLOB, ro_blob, &blob); |
4144 | *ret_blob = ro_blob; |
4145 | } |
4146 | |
4147 | return error; |
4148 | } |
4149 | |
4150 | #if CONFIG_SUPPLEMENTAL_SIGNATURES |
4151 | static void |
4152 | cs_blob_supplement_free(struct cs_blob * const blob) |
4153 | { |
4154 | void *teamid; |
4155 | |
4156 | if (blob != NULL) { |
4157 | if (blob->csb_supplement_teamid != NULL) { |
4158 | teamid = blob->csb_supplement_teamid; |
4159 | vm_size_t teamid_size = strlen(s: blob->csb_supplement_teamid) + 1; |
4160 | kfree_data(teamid, teamid_size); |
4161 | } |
4162 | cs_blob_ro_free(blob); |
4163 | } |
4164 | } |
4165 | #endif |
4166 | |
4167 | static void |
4168 | ubc_cs_blob_adjust_statistics(struct cs_blob const *blob) |
4169 | { |
4170 | /* Note that the atomic ops are not enough to guarantee |
4171 | * correctness: If a blob with an intermediate size is inserted |
4172 | * concurrently, we can lose a peak value assignment. But these |
4173 | * statistics are only advisory anyway, so we're not going to |
4174 | * employ full locking here. (Consequently, we are also okay with |
4175 | * relaxed ordering of those accesses.) |
4176 | */ |
4177 | |
4178 | unsigned int new_cs_blob_count = os_atomic_add(&cs_blob_count, 1, relaxed); |
4179 | if (new_cs_blob_count > os_atomic_load(&cs_blob_count_peak, relaxed)) { |
4180 | os_atomic_store(&cs_blob_count_peak, new_cs_blob_count, relaxed); |
4181 | } |
4182 | |
4183 | size_t new_cs_blob_size = os_atomic_add(&cs_blob_size, blob->csb_mem_size, relaxed); |
4184 | |
4185 | if (new_cs_blob_size > os_atomic_load(&cs_blob_size_peak, relaxed)) { |
4186 | os_atomic_store(&cs_blob_size_peak, new_cs_blob_size, relaxed); |
4187 | } |
4188 | if (blob->csb_mem_size > os_atomic_load(&cs_blob_size_max, relaxed)) { |
4189 | os_atomic_store(&cs_blob_size_max, blob->csb_mem_size, relaxed); |
4190 | } |
4191 | } |
4192 | |
4193 | static void |
4194 | cs_blob_set_cpu_type(struct cs_blob *blob, cpu_type_t cputype) |
4195 | { |
4196 | zalloc_ro_update_field(ZONE_ID_CS_BLOB, blob, csb_cpu_type, &cputype); |
4197 | } |
4198 | |
4199 | __abortlike |
4200 | static void |
4201 | panic_cs_blob_backref_mismatch(struct cs_blob *blob, struct vnode *vp) |
4202 | { |
4203 | panic("cs_blob vnode backref mismatch: blob=%p, vp=%p, " |
4204 | "blob->csb_vnode=%p" , blob, vp, blob->csb_vnode); |
4205 | } |
4206 | |
4207 | void |
4208 | cs_blob_require(struct cs_blob *blob, vnode_t vp) |
4209 | { |
4210 | zone_require_ro(zone_id: ZONE_ID_CS_BLOB, elem_size: sizeof(struct cs_blob), addr: blob); |
4211 | |
4212 | if (vp != NULL && __improbable(blob->csb_vnode != vp)) { |
4213 | panic_cs_blob_backref_mismatch(blob, vp); |
4214 | } |
4215 | } |
4216 | |
4217 | #if CODE_SIGNING_MONITOR |
4218 | |
4219 | /** |
4220 | * Independently verify the authenticity of the code signature through the monitor |
4221 | * environment. This is required as otherwise the monitor won't allow associations |
4222 | * of the code signature with address spaces. |
4223 | * |
4224 | * Once we've verified the code signature, we no longer need to keep around any |
4225 | * provisioning profiles we may have registered with it. AMFI associates profiles |
4226 | * with the monitor during its validation (which happens before the monitor's). |
4227 | */ |
4228 | static errno_t |
4229 | verify_code_signature_monitor( |
4230 | struct cs_blob *cs_blob) |
4231 | { |
4232 | kern_return_t ret = KERN_DENIED; |
4233 | |
4234 | ret = csm_verify_code_signature(cs_blob->csb_csm_obj); |
4235 | if ((ret != KERN_SUCCESS) && (ret != KERN_NOT_SUPPORTED)) { |
4236 | printf("unable to verify code signature with monitor: %d\n" , ret); |
4237 | return EPERM; |
4238 | } |
4239 | |
4240 | ret = csm_disassociate_provisioning_profile(cs_blob->csb_csm_obj); |
4241 | if ((ret != KERN_SUCCESS) && (ret != KERN_NOT_FOUND) && (ret != KERN_NOT_SUPPORTED)) { |
4242 | printf("unable to disassociate profile from code signature: %d\n" , ret); |
4243 | return EPERM; |
4244 | } |
4245 | |
4246 | /* Associate the OSEntitlements kernel object with the monitor */ |
4247 | ret = csm_associate_os_entitlements(cs_blob->csb_csm_obj, cs_blob->csb_entitlements); |
4248 | if ((ret != KERN_SUCCESS) && (ret != KERN_NOT_SUPPORTED)) { |
4249 | printf("unable to associate OSEntitlements with monitor: %d\n" , ret); |
4250 | return EPERM; |
4251 | } |
4252 | |
4253 | return 0; |
4254 | } |
4255 | |
4256 | /** |
4257 | * Register the code signature with the code signing monitor environment. This |
4258 | * will effectively make the blob data immutable, either because the blob memory |
4259 | * will be allocated and managed directory by the monitor, or because the monitor |
4260 | * will lockdown the memory associated with the blob. |
4261 | */ |
4262 | static errno_t |
4263 | register_code_signature_monitor( |
4264 | struct vnode *vnode, |
4265 | struct cs_blob *cs_blob, |
4266 | vm_offset_t code_directory_offset) |
4267 | { |
4268 | kern_return_t ret = KERN_DENIED; |
4269 | vm_address_t monitor_signature_addr = 0; |
4270 | void *monitor_sig_object = NULL; |
4271 | const char *vnode_path_ptr = NULL; |
4272 | |
4273 | /* |
4274 | * Attempt to resolve the path for this vnode and pass it in to the code |
4275 | * signing monitor during registration. |
4276 | */ |
4277 | int vnode_path_len = MAXPATHLEN; |
4278 | char *vnode_path = kalloc_data(vnode_path_len, Z_WAITOK); |
4279 | |
4280 | /* |
4281 | * Taking a reference on the vnode recursively can sometimes lead to a |
4282 | * deadlock on the system. Since we already have a vnode pointer, it means |
4283 | * the caller performed a vnode lookup, which implicitly takes a reference |
4284 | * on the vnode. However, there is more than just having a reference on a |
4285 | * vnode which is important. vnode's also have an iocount, and we must only |
4286 | * access a vnode which has an iocount of greater than 0. Thankfully, all |
4287 | * the conditions which lead to calling this function ensure that this |
4288 | * vnode is safe to access here. |
4289 | * |
4290 | * For more details: rdar://105819068. |
4291 | */ |
4292 | errno_t error = vn_getpath(vnode, vnode_path, &vnode_path_len); |
4293 | if (error == 0) { |
4294 | vnode_path_ptr = vnode_path; |
4295 | } |
4296 | |
4297 | ret = csm_register_code_signature( |
4298 | (vm_address_t)cs_blob->csb_mem_kaddr, |
4299 | cs_blob->csb_mem_size, |
4300 | code_directory_offset, |
4301 | vnode_path_ptr, |
4302 | &monitor_sig_object, |
4303 | &monitor_signature_addr); |
4304 | |
4305 | kfree_data(vnode_path, MAXPATHLEN); |
4306 | vnode_path_ptr = NULL; |
4307 | |
4308 | if (ret == KERN_SUCCESS) { |
4309 | /* Reconstruct the cs_blob if the monitor used its own allocation */ |
4310 | if (monitor_signature_addr != (vm_address_t)cs_blob->csb_mem_kaddr) { |
4311 | vm_address_t monitor_signature_size = cs_blob->csb_mem_size; |
4312 | |
4313 | /* Free the old memory for the blob */ |
4314 | ubc_cs_blob_deallocate( |
4315 | (vm_address_t)cs_blob->csb_mem_kaddr, |
4316 | cs_blob->csb_mem_size); |
4317 | |
4318 | /* Reconstruct critical fields in the blob object */ |
4319 | ubc_cs_blob_reconstruct( |
4320 | cs_blob, |
4321 | monitor_signature_addr, |
4322 | monitor_signature_size, |
4323 | code_directory_offset); |
4324 | |
4325 | /* Mark the signature as monitor managed */ |
4326 | cs_blob->csb_csm_managed = true; |
4327 | } |
4328 | } else if (ret != KERN_NOT_SUPPORTED) { |
4329 | printf("unable to register code signature with monitor: %d\n" , ret); |
4330 | return EPERM; |
4331 | } |
4332 | |
4333 | /* Save the monitor handle for the signature object -- may be NULL */ |
4334 | cs_blob->csb_csm_obj = monitor_sig_object; |
4335 | |
4336 | return 0; |
4337 | } |
4338 | |
4339 | #endif /* CODE_SIGNING_MONITOR */ |
4340 | |
4341 | /** |
4342 | * Accelerate entitlements for a code signature object. When we have a code |
4343 | * signing monitor, this acceleration is done within the monitor which then |
4344 | * passes back a CoreEntitlements query context the kernel can use. When we |
4345 | * don't have a code signing monitor, we accelerate the queries within the |
4346 | * kernel memory itself. |
4347 | * |
4348 | * This function must be called when the storage for the code signature can |
4349 | * no longer change. |
4350 | */ |
4351 | static errno_t |
4352 | accelerate_entitlement_queries( |
4353 | struct cs_blob *cs_blob) |
4354 | { |
4355 | kern_return_t ret = KERN_NOT_SUPPORTED; |
4356 | |
4357 | #if CODE_SIGNING_MONITOR |
4358 | CEQueryContext_t ce_ctx = NULL; |
4359 | const char *signing_id = NULL; |
4360 | |
4361 | ret = csm_accelerate_entitlements(cs_blob->csb_csm_obj, &ce_ctx); |
4362 | if ((ret != KERN_SUCCESS) && (ret != KERN_NOT_SUPPORTED)) { |
4363 | printf("unable to accelerate entitlements through the monitor: %d\n" , ret); |
4364 | return EPERM; |
4365 | } |
4366 | |
4367 | if (ret == KERN_SUCCESS) { |
4368 | /* Call cannot not fail at this stage */ |
4369 | ret = csm_acquire_signing_identifier(cs_blob->csb_csm_obj, &signing_id); |
4370 | assert(ret == KERN_SUCCESS); |
4371 | |
4372 | /* Adjust the OSEntitlements context with AMFI */ |
4373 | ret = amfi->OSEntitlements.adjustContextWithMonitor( |
4374 | cs_blob->csb_entitlements, |
4375 | ce_ctx, |
4376 | cs_blob->csb_csm_obj, |
4377 | signing_id, |
4378 | cs_blob->csb_flags); |
4379 | if (ret != KERN_SUCCESS) { |
4380 | printf("unable to adjust OSEntitlements context with monitor: %d\n" , ret); |
4381 | return EPERM; |
4382 | } |
4383 | |
4384 | return 0; |
4385 | } |
4386 | #endif |
4387 | |
4388 | /* |
4389 | * If we reach here, then either we don't have a code signing monitor, or |
4390 | * the code signing monitor isn't enabled for code signing, in which case, |
4391 | * AMFI is going to accelerate the entitlements context and adjust its |
4392 | * context on its own. |
4393 | */ |
4394 | assert(ret == KERN_NOT_SUPPORTED); |
4395 | |
4396 | ret = amfi->OSEntitlements.adjustContextWithoutMonitor( |
4397 | cs_blob->csb_entitlements, |
4398 | cs_blob); |
4399 | |
4400 | if (ret != KERN_SUCCESS) { |
4401 | printf("unable to adjust OSEntitlements context without monitor: %d\n" , ret); |
4402 | return EPERM; |
4403 | } |
4404 | |
4405 | return 0; |
4406 | } |
4407 | |
4408 | /** |
4409 | * Ensure and validate that some security critical code signing blobs haven't |
4410 | * been stripped off from the code signature. This can happen if an attacker |
4411 | * chose to load a code signature sans these critical blobs, or if there is a |
4412 | * bug in reconstitution logic which remove these blobs from the code signature. |
4413 | */ |
4414 | static errno_t |
4415 | validate_auxiliary_signed_blobs( |
4416 | struct cs_blob *cs_blob) |
4417 | { |
4418 | struct cs_blob_identifier { |
4419 | uint32_t cs_slot; |
4420 | uint32_t cs_magic; |
4421 | }; |
4422 | |
4423 | const struct cs_blob_identifier identifiers[] = { |
4424 | {CSSLOT_LAUNCH_CONSTRAINT_SELF, CSMAGIC_EMBEDDED_LAUNCH_CONSTRAINT}, |
4425 | {CSSLOT_LAUNCH_CONSTRAINT_PARENT, CSMAGIC_EMBEDDED_LAUNCH_CONSTRAINT}, |
4426 | {CSSLOT_LAUNCH_CONSTRAINT_RESPONSIBLE, CSMAGIC_EMBEDDED_LAUNCH_CONSTRAINT}, |
4427 | {CSSLOT_LIBRARY_CONSTRAINT, CSMAGIC_EMBEDDED_LAUNCH_CONSTRAINT} |
4428 | }; |
4429 | const uint32_t num_identifiers = sizeof(identifiers) / sizeof(identifiers[0]); |
4430 | |
4431 | for (uint32_t i = 0; i < num_identifiers; i++) { |
4432 | errno_t err = csblob_find_special_slot_blob( |
4433 | csblob: cs_blob, |
4434 | slot: identifiers[i].cs_slot, |
4435 | magic: identifiers[i].cs_magic, |
4436 | NULL, |
4437 | NULL); |
4438 | |
4439 | if (err != 0) { |
4440 | printf("unable to validate security-critical blob: %d [%u|%u]\n" , |
4441 | err, identifiers[i].cs_slot, identifiers[i].cs_magic); |
4442 | |
4443 | return EPERM; |
4444 | } |
4445 | } |
4446 | |
4447 | return 0; |
4448 | } |
4449 | |
4450 | /** |
4451 | * Setup multi-level hashing for the code signature. This isn't supported on most |
4452 | * shipping devices, but on ones where it is, it can result in significant savings |
4453 | * of memory from the code signature standpoint. |
4454 | * |
4455 | * Multi-level hashing is used to condense the code directory hashes in order to |
4456 | * improve memory consumption. We take four 4K page hashes, and condense them into |
4457 | * a single 16K hash, hence reducing the space consumed by the code directory by |
4458 | * about ~75%. |
4459 | */ |
4460 | static errno_t |
4461 | setup_multilevel_hashing( |
4462 | struct cs_blob *cs_blob) |
4463 | { |
4464 | code_signing_monitor_type_t monitor_type = CS_MONITOR_TYPE_NONE; |
4465 | errno_t err = -1; |
4466 | |
4467 | /* |
4468 | * When we have a code signing monitor, we do not support multi-level hashing |
4469 | * since the code signature data is expected to be locked within memory which |
4470 | * cannot be written to by the kernel. |
4471 | * |
4472 | * Even when the code signing monitor isn't explicitly enabled, there are other |
4473 | * reasons for not performing multi-level hashing. For instance, Rosetta creates |
4474 | * issues with multi-level hashing on Apple Silicon Macs. |
4475 | */ |
4476 | code_signing_configuration(monitor_type: &monitor_type, NULL); |
4477 | if (monitor_type != CS_MONITOR_TYPE_NONE) { |
4478 | return 0; |
4479 | } |
4480 | |
4481 | /* We need to check if multi-level hashing is supported for this blob */ |
4482 | if (ubc_cs_supports_multilevel_hash(blob: cs_blob) == false) { |
4483 | return 0; |
4484 | } |
4485 | |
4486 | err = ubc_cs_convert_to_multilevel_hash(blob: cs_blob); |
4487 | if (err != 0) { |
4488 | printf("unable to setup multi-level hashing: %d\n" , err); |
4489 | return err; |
4490 | } |
4491 | |
4492 | assert(cs_blob->csb_reconstituted == true); |
4493 | return 0; |
4494 | } |
4495 | |
4496 | /** |
4497 | * Once code signature validation is complete, we can remove even more blobs from the |
4498 | * code signature as they are no longer needed. This goes on to conserve even more |
4499 | * system memory. |
4500 | */ |
4501 | static errno_t |
4502 | reconstitute_code_signature_2nd_stage( |
4503 | struct cs_blob *cs_blob) |
4504 | { |
4505 | kern_return_t ret = KERN_NOT_SUPPORTED; |
4506 | errno_t err = EPERM; |
4507 | |
4508 | /* If we never reconstituted before, we won't be reconstituting again */ |
4509 | if (cs_blob->csb_reconstituted == false) { |
4510 | return 0; |
4511 | } |
4512 | |
4513 | #if CODE_SIGNING_MONITOR |
4514 | /* |
4515 | * When we have a code signing monitor, the code signature is immutable until the |
4516 | * monitor decides to unlock parts of it. Therefore, 2nd stage reconstitution takes |
4517 | * place in the monitor when we have a monitor available. |
4518 | * |
4519 | * If the monitor isn't enforcing code signing (in which case the code signature is |
4520 | * NOT immutable), then we perform 2nd stage reconstitution within the kernel itself. |
4521 | */ |
4522 | vm_address_t unneeded_addr = 0; |
4523 | vm_size_t unneeded_size = 0; |
4524 | |
4525 | ret = csm_reconstitute_code_signature( |
4526 | cs_blob->csb_csm_obj, |
4527 | &unneeded_addr, |
4528 | &unneeded_size); |
4529 | |
4530 | if ((ret == KERN_SUCCESS) && unneeded_addr && unneeded_size) { |
4531 | /* Free the unneded part of the blob */ |
4532 | kmem_free(kernel_map, unneeded_addr, unneeded_size); |
4533 | |
4534 | /* Adjust the size in the blob object */ |
4535 | cs_blob->csb_mem_size -= unneeded_size; |
4536 | } |
4537 | #endif |
4538 | |
4539 | if (ret == KERN_SUCCESS) { |
4540 | goto success; |
4541 | } else if (ret != KERN_NOT_SUPPORTED) { |
4542 | /* |
4543 | * A monitor environment is available, and it failed in performing 2nd stage |
4544 | * reconstitution. This is a fatal issue for code signing validation. |
4545 | */ |
4546 | printf("unable to reconstitute code signature through monitor: %d\n" , ret); |
4547 | return EPERM; |
4548 | } |
4549 | |
4550 | /* No monitor available if we reached here */ |
4551 | err = ubc_cs_reconstitute_code_signature_2nd_stage(blob: cs_blob); |
4552 | if (err != 0) { |
4553 | return err; |
4554 | } |
4555 | |
4556 | success: |
4557 | /* |
4558 | * Regardless of whether we are performing 2nd stage reconstitution in the monitor |
4559 | * or in the kernel, we remove references to XML entitlements from the blob here. |
4560 | * None of the 2nd stage reconstitution code ever keeps these around, and they have |
4561 | * been explicitly deprecated and disallowed. |
4562 | */ |
4563 | cs_blob->csb_entitlements_blob = NULL; |
4564 | |
4565 | return 0; |
4566 | } |
4567 | |
4568 | /** |
4569 | * A code signature blob often contains blob which aren't needed in the kernel. Since |
4570 | * the code signature is wired into kernel memory for the time it is used, it behooves |
4571 | * us to remove any blobs we have no need for in order to conserve memory. |
4572 | * |
4573 | * Some platforms support copying the entire SuperBlob stored in kernel memory into |
4574 | * userspace memory through the "csops" system call. There is an expectation that when |
4575 | * this happens, all the blobs which were a part of the code signature are copied in |
4576 | * to userspace memory. As a result, these platforms cannot reconstitute the code |
4577 | * signature since, or rather, these platforms cannot remove blobs from the signature, |
4578 | * thereby making reconstitution useless. |
4579 | */ |
4580 | static errno_t |
4581 | reconstitute_code_signature( |
4582 | struct cs_blob *cs_blob) |
4583 | { |
4584 | CS_CodeDirectory *code_directory = NULL; |
4585 | vm_address_t signature_addr = 0; |
4586 | vm_size_t signature_size = 0; |
4587 | vm_offset_t code_directory_offset = 0; |
4588 | bool platform_supports_reconstitution = false; |
4589 | |
4590 | #if CONFIG_CODE_SIGNATURE_RECONSTITUTION |
4591 | platform_supports_reconstitution = true; |
4592 | #endif |
4593 | |
4594 | /* |
4595 | * We can skip reconstitution if the code signing monitor isn't available or not |
4596 | * enabled. But if we do have a monitor, then reconsitution becomes required, as |
4597 | * there is an expectation of performing 2nd stage reconstitution through the |
4598 | * monitor itself. |
4599 | */ |
4600 | if (platform_supports_reconstitution == false) { |
4601 | #if CODE_SIGNING_MONITOR |
4602 | if (csm_enabled() == true) { |
4603 | printf("reconstitution required when code signing monitor is enabled\n" ); |
4604 | return EPERM; |
4605 | } |
4606 | #endif |
4607 | return 0; |
4608 | } |
4609 | |
4610 | errno_t err = ubc_cs_reconstitute_code_signature( |
4611 | blob: cs_blob, |
4612 | ret_mem_kaddr: &signature_addr, |
4613 | ret_mem_size: &signature_size, |
4614 | code_directory_size: 0, |
4615 | code_directory: &code_directory); |
4616 | |
4617 | if (err != 0) { |
4618 | printf("unable to reconstitute code signature: %d\n" , err); |
4619 | return err; |
4620 | } |
4621 | |
4622 | /* Calculate the code directory offset */ |
4623 | code_directory_offset = (vm_offset_t)code_directory - signature_addr; |
4624 | |
4625 | /* Reconstitution allocates new memory -- free the old one */ |
4626 | ubc_cs_blob_deallocate(blob_addr: (vm_address_t)cs_blob->csb_mem_kaddr, blob_size: cs_blob->csb_mem_size); |
4627 | |
4628 | /* Reconstruct critical fields in the blob object */ |
4629 | ubc_cs_blob_reconstruct( |
4630 | cs_blob, |
4631 | signature_addr, |
4632 | signature_size, |
4633 | code_directory_offset); |
4634 | |
4635 | /* Mark the object as reconstituted */ |
4636 | cs_blob->csb_reconstituted = true; |
4637 | |
4638 | return 0; |
4639 | } |
4640 | |
4641 | int |
4642 | ubc_cs_blob_add( |
4643 | struct vnode *vp, |
4644 | uint32_t platform, |
4645 | cpu_type_t cputype, |
4646 | cpu_subtype_t cpusubtype, |
4647 | off_t base_offset, |
4648 | vm_address_t *addr, |
4649 | vm_size_t size, |
4650 | struct image_params *imgp, |
4651 | __unused int flags, |
4652 | struct cs_blob **ret_blob) |
4653 | { |
4654 | ptrauth_generic_signature_t cs_blob_sig = {0}; |
4655 | struct ubc_info *uip = NULL; |
4656 | struct cs_blob tmp_blob = {0}; |
4657 | struct cs_blob *blob_ro = NULL; |
4658 | struct cs_blob *oblob = NULL; |
4659 | CS_CodeDirectory const *cd = NULL; |
4660 | off_t blob_start_offset = 0; |
4661 | off_t blob_end_offset = 0; |
4662 | boolean_t record_mtime = false; |
4663 | kern_return_t kr = KERN_DENIED; |
4664 | errno_t error = -1; |
4665 | |
4666 | #if HAS_APPLE_PAC |
4667 | void *signed_entitlements = NULL; |
4668 | #if CODE_SIGNING_MONITOR |
4669 | void *signed_monitor_obj = NULL; |
4670 | #endif |
4671 | #endif |
4672 | |
4673 | if (ret_blob) { |
4674 | *ret_blob = NULL; |
4675 | } |
4676 | |
4677 | /* |
4678 | * Create the struct cs_blob abstract data type which will get attached to |
4679 | * the vnode object. This function also validates the structural integrity |
4680 | * of the code signature blob being passed in. |
4681 | * |
4682 | * We initialize a temporary blob whose contents are then copied into an RO |
4683 | * blob which we allocate from the read-only allocator. |
4684 | */ |
4685 | error = cs_blob_init_validated(addr, size, blob: &tmp_blob, ret_cd: &cd); |
4686 | if (error != 0) { |
4687 | printf("unable to create a validated cs_blob object: %d\n" , error); |
4688 | return error; |
4689 | } |
4690 | |
4691 | tmp_blob.csb_cpu_type = cputype; |
4692 | tmp_blob.csb_cpu_subtype = cpusubtype & ~CPU_SUBTYPE_MASK; |
4693 | tmp_blob.csb_base_offset = base_offset; |
4694 | |
4695 | /* Perform 1st stage reconstitution */ |
4696 | error = reconstitute_code_signature(cs_blob: &tmp_blob); |
4697 | if (error != 0) { |
4698 | goto out; |
4699 | } |
4700 | |
4701 | /* |
4702 | * There is a strong design pattern we have to follow carefully within this |
4703 | * function. Since we're storing the struct cs_blob within RO-allocated |
4704 | * memory, it is immutable to modifications from within the kernel itself. |
4705 | * |
4706 | * However, before the contents of the blob are transferred to the immutable |
4707 | * cs_blob, they are kept on the stack. In order to protect against a kernel |
4708 | * R/W attacker, we must protect this stack variable. Most importantly, any |
4709 | * code paths which can block for a while must compute a PAC signature over |
4710 | * the stack variable, then perform the blocking operation, and then ensure |
4711 | * that the PAC signature over the stack variable is still valid to ensure |
4712 | * that an attacker did not overwrite contents of the blob by introducing a |
4713 | * maliciously long blocking operation, giving them the time required to go |
4714 | * and overwrite the contents of the blob. |
4715 | * |
4716 | * The most important fields to protect here are the OSEntitlements and the |
4717 | * code signing monitor object references. For these ones, we keep around |
4718 | * extra signed pointers diversified against the read-only blobs' memory |
4719 | * and then update the stack variable with these before updating the full |
4720 | * read-only blob. |
4721 | */ |
4722 | |
4723 | blob_ro = zalloc_ro(ZONE_ID_CS_BLOB, Z_WAITOK | Z_NOFAIL); |
4724 | assert(blob_ro != NULL); |
4725 | |
4726 | tmp_blob.csb_ro_addr = blob_ro; |
4727 | tmp_blob.csb_vnode = vp; |
4728 | |
4729 | /* AMFI needs to see the current blob state at the RO address */ |
4730 | zalloc_ro_update_elem(ZONE_ID_CS_BLOB, blob_ro, &tmp_blob); |
4731 | |
4732 | #if CODE_SIGNING_MONITOR |
4733 | error = register_code_signature_monitor( |
4734 | vp, |
4735 | &tmp_blob, |
4736 | (vm_offset_t)tmp_blob.csb_cd - (vm_offset_t)tmp_blob.csb_mem_kaddr); |
4737 | |
4738 | if (error != 0) { |
4739 | goto out; |
4740 | } |
4741 | |
4742 | #if HAS_APPLE_PAC |
4743 | signed_monitor_obj = ptrauth_sign_unauthenticated( |
4744 | tmp_blob.csb_csm_obj, |
4745 | ptrauth_key_process_independent_data, |
4746 | ptrauth_blend_discriminator(&blob_ro->csb_csm_obj, |
4747 | OS_PTRAUTH_DISCRIMINATOR("cs_blob.csb_csm_obj" ))); |
4748 | #endif /* HAS_APPLE_PAC */ |
4749 | |
4750 | #endif /* CODE_SIGNING_MONITOR */ |
4751 | |
4752 | #if CONFIG_MACF |
4753 | unsigned int cs_flags = tmp_blob.csb_flags; |
4754 | unsigned int signer_type = tmp_blob.csb_signer_type; |
4755 | |
4756 | error = mac_vnode_check_signature( |
4757 | vp, |
4758 | cs_blob: &tmp_blob, |
4759 | imgp, |
4760 | cs_flags: &cs_flags, |
4761 | signer_type: &signer_type, |
4762 | flags, |
4763 | platform); |
4764 | |
4765 | if (error != 0) { |
4766 | printf("validation of code signature failed through MACF policy: %d\n" , error); |
4767 | goto out; |
4768 | } |
4769 | |
4770 | #if HAS_APPLE_PAC |
4771 | signed_entitlements = ptrauth_sign_unauthenticated( |
4772 | tmp_blob.csb_entitlements, |
4773 | ptrauth_key_process_independent_data, |
4774 | ptrauth_blend_discriminator(&blob_ro->csb_entitlements, |
4775 | OS_PTRAUTH_DISCRIMINATOR("cs_blob.csb_entitlements" ))); |
4776 | #endif |
4777 | |
4778 | tmp_blob.csb_flags = cs_flags; |
4779 | tmp_blob.csb_signer_type = signer_type; |
4780 | |
4781 | if (tmp_blob.csb_flags & CS_PLATFORM_BINARY) { |
4782 | tmp_blob.csb_platform_binary = 1; |
4783 | tmp_blob.csb_platform_path = !!(tmp_blob.csb_flags & CS_PLATFORM_PATH); |
4784 | tmp_blob.csb_teamid = NULL; |
4785 | } else { |
4786 | tmp_blob.csb_platform_binary = 0; |
4787 | tmp_blob.csb_platform_path = 0; |
4788 | } |
4789 | |
4790 | if ((flags & MAC_VNODE_CHECK_DYLD_SIM) && !tmp_blob.csb_platform_binary) { |
4791 | printf("dyld simulator runtime is not apple signed: proc: %d\n" , |
4792 | proc_getpid(current_proc())); |
4793 | |
4794 | error = EPERM; |
4795 | goto out; |
4796 | } |
4797 | #endif /* CONFIG_MACF */ |
4798 | |
4799 | #if CODE_SIGNING_MONITOR |
4800 | error = verify_code_signature_monitor(&tmp_blob); |
4801 | if (error != 0) { |
4802 | goto out; |
4803 | } |
4804 | #endif |
4805 | |
4806 | /* Perform 2nd stage reconstitution */ |
4807 | error = reconstitute_code_signature_2nd_stage(cs_blob: &tmp_blob); |
4808 | if (error != 0) { |
4809 | goto out; |
4810 | } |
4811 | |
4812 | /* Setup any multi-level hashing for the code signature */ |
4813 | error = setup_multilevel_hashing(&tmp_blob); |
4814 | if (error != 0) { |
4815 | goto out; |
4816 | } |
4817 | |
4818 | /* Ensure security critical auxiliary blobs still exist */ |
4819 | error = validate_auxiliary_signed_blobs(cs_blob: &tmp_blob); |
4820 | if (error != 0) { |
4821 | goto out; |
4822 | } |
4823 | |
4824 | /* |
4825 | * Accelerate the entitlement queries for this code signature. This must |
4826 | * be done only after we know that the code signature pointers within the |
4827 | * struct cs_blob aren't going to be shifted around anymore, which is why |
4828 | * this acceleration is done after setting up multilevel hashing, since |
4829 | * that is the last part of signature validation which can shift the code |
4830 | * signature around. |
4831 | */ |
4832 | error = accelerate_entitlement_queries(cs_blob: &tmp_blob); |
4833 | if (error != 0) { |
4834 | goto out; |
4835 | } |
4836 | |
4837 | /* |
4838 | * Parse and set the Team ID for this code signature. This only needs to |
4839 | * happen when the signature isn't marked as platform. Like above, this |
4840 | * has to happen after we know the pointers within struct cs_blob aren't |
4841 | * going to be shifted anymore. |
4842 | */ |
4843 | if ((tmp_blob.csb_flags & CS_PLATFORM_BINARY) == 0) { |
4844 | tmp_blob.csb_teamid = csblob_parse_teamid(csblob: &tmp_blob); |
4845 | } |
4846 | |
4847 | /* |
4848 | * Validate the code signing blob's coverage. Ideally, we can just do this |
4849 | * in the beginning, right after structural validation, however, multilevel |
4850 | * hashing can change some offets. |
4851 | */ |
4852 | blob_start_offset = tmp_blob.csb_base_offset + tmp_blob.csb_start_offset; |
4853 | blob_end_offset = tmp_blob.csb_base_offset + tmp_blob.csb_end_offset; |
4854 | if (blob_start_offset >= blob_end_offset) { |
4855 | error = EINVAL; |
4856 | goto out; |
4857 | } else if (blob_start_offset < 0 || blob_end_offset <= 0) { |
4858 | error = EINVAL; |
4859 | goto out; |
4860 | } |
4861 | |
4862 | /* |
4863 | * The vnode_lock, linked list traversal, and marking of the memory object as |
4864 | * signed can all be blocking operations. Compute a PAC over the tmp_blob. |
4865 | */ |
4866 | cs_blob_sig = ptrauth_utils_sign_blob_generic( |
4867 | ptr: &tmp_blob, |
4868 | len_bytes: sizeof(tmp_blob), |
4869 | OS_PTRAUTH_DISCRIMINATOR("ubc_cs_blob_add.blocking_op0" ), |
4870 | PTRAUTH_ADDR_DIVERSIFY); |
4871 | |
4872 | vnode_lock(vp); |
4873 | if (!UBCINFOEXISTS(vp)) { |
4874 | vnode_unlock(vp); |
4875 | error = ENOENT; |
4876 | goto out; |
4877 | } |
4878 | uip = vp->v_ubcinfo; |
4879 | |
4880 | /* check if this new blob overlaps with an existing blob */ |
4881 | for (oblob = ubc_get_cs_blobs(vp); |
4882 | oblob != NULL; |
4883 | oblob = oblob->csb_next) { |
4884 | off_t oblob_start_offset, oblob_end_offset; |
4885 | |
4886 | if (tmp_blob.csb_signer_type != oblob->csb_signer_type) { // signer type needs to be the same for slices |
4887 | vnode_unlock(vp); |
4888 | error = EALREADY; |
4889 | goto out; |
4890 | } else if (tmp_blob.csb_platform_binary) { //platform binary needs to be the same for app slices |
4891 | if (!oblob->csb_platform_binary) { |
4892 | vnode_unlock(vp); |
4893 | error = EALREADY; |
4894 | goto out; |
4895 | } |
4896 | } else if (tmp_blob.csb_teamid) { //teamid binary needs to be the same for app slices |
4897 | if (oblob->csb_platform_binary || |
4898 | oblob->csb_teamid == NULL || |
4899 | strcmp(s1: oblob->csb_teamid, s2: tmp_blob.csb_teamid) != 0) { |
4900 | vnode_unlock(vp); |
4901 | error = EALREADY; |
4902 | goto out; |
4903 | } |
4904 | } else { // non teamid binary needs to be the same for app slices |
4905 | if (oblob->csb_platform_binary || |
4906 | oblob->csb_teamid != NULL) { |
4907 | vnode_unlock(vp); |
4908 | error = EALREADY; |
4909 | goto out; |
4910 | } |
4911 | } |
4912 | |
4913 | oblob_start_offset = (oblob->csb_base_offset + |
4914 | oblob->csb_start_offset); |
4915 | oblob_end_offset = (oblob->csb_base_offset + |
4916 | oblob->csb_end_offset); |
4917 | if (blob_start_offset >= oblob_end_offset || |
4918 | blob_end_offset <= oblob_start_offset) { |
4919 | /* no conflict with this existing blob */ |
4920 | } else { |
4921 | /* conflict ! */ |
4922 | if (blob_start_offset == oblob_start_offset && |
4923 | blob_end_offset == oblob_end_offset && |
4924 | tmp_blob.csb_mem_size == oblob->csb_mem_size && |
4925 | tmp_blob.csb_flags == oblob->csb_flags && |
4926 | (tmp_blob.csb_cpu_type == CPU_TYPE_ANY || |
4927 | oblob->csb_cpu_type == CPU_TYPE_ANY || |
4928 | tmp_blob.csb_cpu_type == oblob->csb_cpu_type) && |
4929 | !bcmp(s1: tmp_blob.csb_cdhash, |
4930 | s2: oblob->csb_cdhash, |
4931 | n: CS_CDHASH_LEN)) { |
4932 | /* |
4933 | * We already have this blob: |
4934 | * we'll return success but |
4935 | * throw away the new blob. |
4936 | */ |
4937 | if (oblob->csb_cpu_type == CPU_TYPE_ANY) { |
4938 | /* |
4939 | * The old blob matches this one |
4940 | * but doesn't have any CPU type. |
4941 | * Update it with whatever the caller |
4942 | * provided this time. |
4943 | */ |
4944 | cs_blob_set_cpu_type(blob: oblob, cputype); |
4945 | } |
4946 | |
4947 | /* The signature is still accepted, so update the |
4948 | * generation count. */ |
4949 | uip->cs_add_gen = cs_blob_generation_count; |
4950 | |
4951 | vnode_unlock(vp); |
4952 | if (ret_blob) { |
4953 | *ret_blob = oblob; |
4954 | } |
4955 | error = EAGAIN; |
4956 | goto out; |
4957 | } else { |
4958 | /* different blob: reject the new one */ |
4959 | vnode_unlock(vp); |
4960 | error = EALREADY; |
4961 | goto out; |
4962 | } |
4963 | } |
4964 | } |
4965 | |
4966 | /* mark this vnode's VM object as having "signed pages" */ |
4967 | kr = memory_object_signed(control: uip->ui_control, TRUE); |
4968 | if (kr != KERN_SUCCESS) { |
4969 | vnode_unlock(vp); |
4970 | error = ENOENT; |
4971 | goto out; |
4972 | } |
4973 | |
4974 | if (uip->cs_blobs == NULL) { |
4975 | /* loading 1st blob: record the file's current "modify time" */ |
4976 | record_mtime = TRUE; |
4977 | } |
4978 | |
4979 | /* set the generation count for cs_blobs */ |
4980 | uip->cs_add_gen = cs_blob_generation_count; |
4981 | |
4982 | /* Authenticate the PAC signature after blocking operation */ |
4983 | ptrauth_utils_auth_blob_generic( |
4984 | ptr: &tmp_blob, |
4985 | len_bytes: sizeof(tmp_blob), |
4986 | OS_PTRAUTH_DISCRIMINATOR("ubc_cs_blob_add.blocking_op0" ), |
4987 | PTRAUTH_ADDR_DIVERSIFY, |
4988 | signature: cs_blob_sig); |
4989 | |
4990 | /* Update the system statistics for code signatures blobs */ |
4991 | ubc_cs_blob_adjust_statistics(blob: &tmp_blob); |
4992 | |
4993 | /* Update the list pointer to reference other blobs for this vnode */ |
4994 | tmp_blob.csb_next = uip->cs_blobs; |
4995 | |
4996 | #if HAS_APPLE_PAC |
4997 | /* |
4998 | * Update all the critical pointers in the blob with the RO diversified |
4999 | * values before updating the read-only blob with the full contents of |
5000 | * the struct cs_blob. We need to use memcpy here as otherwise a simple |
5001 | * assignment will cause the compiler to re-sign using the stack variable |
5002 | * as the address diversifier. |
5003 | */ |
5004 | memcpy(dst: (void*)&tmp_blob.csb_entitlements, src: &signed_entitlements, n: sizeof(void*)); |
5005 | #if CODE_SIGNING_MONITOR |
5006 | memcpy((void*)&tmp_blob.csb_csm_obj, &signed_monitor_obj, sizeof(void*)); |
5007 | #endif |
5008 | #endif |
5009 | zalloc_ro_update_elem(ZONE_ID_CS_BLOB, blob_ro, &tmp_blob); |
5010 | |
5011 | /* Add a fence to ensure writes to the blob are visible on all threads */ |
5012 | os_atomic_thread_fence(seq_cst); |
5013 | |
5014 | /* |
5015 | * Add the cs_blob to the front of the list of blobs for this vnode. We |
5016 | * add to the front of the list, and we never remove a blob from the list |
5017 | * which means ubc_cs_get_blobs can return whatever the top of the list |
5018 | * is, while still keeping the list valid. Useful for if we validate a |
5019 | * page while adding in a new blob for this vnode. |
5020 | */ |
5021 | uip->cs_blobs = blob_ro; |
5022 | |
5023 | /* Make sure to reload pointer from uip to double check */ |
5024 | if (uip->cs_blobs->csb_next) { |
5025 | zone_require_ro(zone_id: ZONE_ID_CS_BLOB, elem_size: sizeof(struct cs_blob), addr: uip->cs_blobs->csb_next); |
5026 | } |
5027 | |
5028 | if (cs_debug > 1) { |
5029 | proc_t p; |
5030 | const char *name = vnode_getname_printable(vp); |
5031 | p = current_proc(); |
5032 | printf("CODE SIGNING: proc %d(%s) " |
5033 | "loaded %s signatures for file (%s) " |
5034 | "range 0x%llx:0x%llx flags 0x%x\n" , |
5035 | proc_getpid(p), p->p_comm, |
5036 | blob_ro->csb_cpu_type == -1 ? "detached" : "embedded" , |
5037 | name, |
5038 | blob_ro->csb_base_offset + blob_ro->csb_start_offset, |
5039 | blob_ro->csb_base_offset + blob_ro->csb_end_offset, |
5040 | blob_ro->csb_flags); |
5041 | vnode_putname_printable(name); |
5042 | } |
5043 | |
5044 | vnode_unlock(vp); |
5045 | |
5046 | if (record_mtime) { |
5047 | vnode_mtime(vp, &uip->cs_mtime, vfs_context_current()); |
5048 | } |
5049 | |
5050 | if (ret_blob) { |
5051 | *ret_blob = blob_ro; |
5052 | } |
5053 | |
5054 | error = 0; /* success ! */ |
5055 | |
5056 | out: |
5057 | if (error) { |
5058 | if (error != EAGAIN) { |
5059 | printf("check_signature[pid: %d]: error = %d\n" , proc_getpid(current_proc()), error); |
5060 | } |
5061 | |
5062 | cs_blob_cleanup(blob: &tmp_blob); |
5063 | if (blob_ro) { |
5064 | zfree_ro(ZONE_ID_CS_BLOB, blob_ro); |
5065 | } |
5066 | } |
5067 | |
5068 | if (error == EAGAIN) { |
5069 | /* |
5070 | * See above: error is EAGAIN if we were asked |
5071 | * to add an existing blob again. We cleaned the new |
5072 | * blob and we want to return success. |
5073 | */ |
5074 | error = 0; |
5075 | } |
5076 | |
5077 | return error; |
5078 | } |
5079 | |
5080 | #if CONFIG_SUPPLEMENTAL_SIGNATURES |
5081 | int |
5082 | ubc_cs_blob_add_supplement( |
5083 | struct vnode *vp, |
5084 | struct vnode *orig_vp, |
5085 | off_t base_offset, |
5086 | vm_address_t *addr, |
5087 | vm_size_t size, |
5088 | struct cs_blob **ret_blob) |
5089 | { |
5090 | kern_return_t kr; |
5091 | struct ubc_info *uip, *orig_uip; |
5092 | int error; |
5093 | struct cs_blob tmp_blob; |
5094 | struct cs_blob *orig_blob; |
5095 | struct cs_blob *blob_ro = NULL; |
5096 | CS_CodeDirectory const *cd; |
5097 | off_t blob_start_offset, blob_end_offset; |
5098 | |
5099 | if (ret_blob) { |
5100 | *ret_blob = NULL; |
5101 | } |
5102 | |
5103 | /* Create the struct cs_blob wrapper that will be attached to the vnode. |
5104 | * Validates the passed in blob in the process. */ |
5105 | error = cs_blob_init_validated(addr, size, blob: &tmp_blob, ret_cd: &cd); |
5106 | |
5107 | if (error != 0) { |
5108 | printf("malformed code signature supplement blob: %d\n" , error); |
5109 | return error; |
5110 | } |
5111 | |
5112 | tmp_blob.csb_cpu_type = -1; |
5113 | tmp_blob.csb_base_offset = base_offset; |
5114 | |
5115 | tmp_blob.csb_reconstituted = false; |
5116 | |
5117 | vnode_lock(orig_vp); |
5118 | if (!UBCINFOEXISTS(vp: orig_vp)) { |
5119 | vnode_unlock(orig_vp); |
5120 | error = ENOENT; |
5121 | goto out; |
5122 | } |
5123 | |
5124 | orig_uip = orig_vp->v_ubcinfo; |
5125 | |
5126 | /* check that the supplement's linked cdhash matches a cdhash of |
5127 | * the target image. |
5128 | */ |
5129 | |
5130 | if (tmp_blob.csb_linkage_hashtype == NULL) { |
5131 | proc_t p; |
5132 | const char *iname = vnode_getname_printable(vp); |
5133 | p = current_proc(); |
5134 | |
5135 | printf("CODE SIGNING: proc %d(%s) supplemental signature for file (%s) " |
5136 | "is not a supplemental.\n" , |
5137 | proc_getpid(p), p->p_comm, iname); |
5138 | |
5139 | error = EINVAL; |
5140 | |
5141 | vnode_putname_printable(name: iname); |
5142 | vnode_unlock(orig_vp); |
5143 | goto out; |
5144 | } |
5145 | bool found_but_not_valid = false; |
5146 | for (orig_blob = ubc_get_cs_blobs(orig_vp); orig_blob != NULL; |
5147 | orig_blob = orig_blob->csb_next) { |
5148 | if (orig_blob->csb_hashtype == tmp_blob.csb_linkage_hashtype && |
5149 | memcmp(s1: orig_blob->csb_cdhash, s2: tmp_blob.csb_linkage, n: CS_CDHASH_LEN) == 0) { |
5150 | // Found match! |
5151 | found_but_not_valid = ((orig_blob->csb_flags & CS_VALID) != CS_VALID); |
5152 | break; |
5153 | } |
5154 | } |
5155 | |
5156 | if (orig_blob == NULL || found_but_not_valid) { |
5157 | // Not found. |
5158 | |
5159 | proc_t p; |
5160 | const char *iname = vnode_getname_printable(vp); |
5161 | p = current_proc(); |
5162 | |
5163 | error = (orig_blob == NULL) ? ESRCH : EPERM; |
5164 | |
5165 | printf("CODE SIGNING: proc %d(%s) supplemental signature for file (%s) " |
5166 | "does not match any attached cdhash (error: %d).\n" , |
5167 | proc_getpid(p), p->p_comm, iname, error); |
5168 | |
5169 | vnode_putname_printable(name: iname); |
5170 | vnode_unlock(orig_vp); |
5171 | goto out; |
5172 | } |
5173 | |
5174 | vnode_unlock(orig_vp); |
5175 | |
5176 | blob_ro = zalloc_ro(ZONE_ID_CS_BLOB, Z_WAITOK | Z_NOFAIL); |
5177 | tmp_blob.csb_ro_addr = blob_ro; |
5178 | tmp_blob.csb_vnode = vp; |
5179 | |
5180 | /* AMFI needs to see the current blob state at the RO address. */ |
5181 | zalloc_ro_update_elem(ZONE_ID_CS_BLOB, blob_ro, &tmp_blob); |
5182 | |
5183 | // validate the signature against policy! |
5184 | #if CONFIG_MACF |
5185 | unsigned int signer_type = tmp_blob.csb_signer_type; |
5186 | error = mac_vnode_check_supplemental_signature(vp, cs_blob: &tmp_blob, linked_vp: orig_vp, linked_cs_blob: orig_blob, signer_type: &signer_type); |
5187 | |
5188 | tmp_blob.csb_signer_type = signer_type; |
5189 | |
5190 | if (error) { |
5191 | if (cs_debug) { |
5192 | printf("check_supplemental_signature[pid: %d], error = %d\n" , proc_getpid(current_proc()), error); |
5193 | } |
5194 | goto out; |
5195 | } |
5196 | #endif |
5197 | |
5198 | // We allowed the supplemental signature blob so |
5199 | // copy the platform bit or team-id from the linked signature and whether or not the original is developer code |
5200 | tmp_blob.csb_platform_binary = 0; |
5201 | tmp_blob.csb_platform_path = 0; |
5202 | if (orig_blob->csb_platform_binary == 1) { |
5203 | tmp_blob.csb_platform_binary = orig_blob->csb_platform_binary; |
5204 | tmp_blob.csb_platform_path = orig_blob->csb_platform_path; |
5205 | } else if (orig_blob->csb_teamid != NULL) { |
5206 | vm_size_t teamid_size = strlen(s: orig_blob->csb_teamid) + 1; |
5207 | tmp_blob.csb_supplement_teamid = kalloc_data(teamid_size, Z_WAITOK); |
5208 | if (tmp_blob.csb_supplement_teamid == NULL) { |
5209 | error = ENOMEM; |
5210 | goto out; |
5211 | } |
5212 | strlcpy(dst: tmp_blob.csb_supplement_teamid, src: orig_blob->csb_teamid, n: teamid_size); |
5213 | } |
5214 | tmp_blob.csb_flags = (orig_blob->csb_flags & CS_DEV_CODE); |
5215 | |
5216 | // Validate the blob's coverage |
5217 | blob_start_offset = tmp_blob.csb_base_offset + tmp_blob.csb_start_offset; |
5218 | blob_end_offset = tmp_blob.csb_base_offset + tmp_blob.csb_end_offset; |
5219 | |
5220 | if (blob_start_offset >= blob_end_offset || blob_start_offset < 0 || blob_end_offset <= 0) { |
5221 | /* reject empty or backwards blob */ |
5222 | error = EINVAL; |
5223 | goto out; |
5224 | } |
5225 | |
5226 | vnode_lock(vp); |
5227 | if (!UBCINFOEXISTS(vp)) { |
5228 | vnode_unlock(vp); |
5229 | error = ENOENT; |
5230 | goto out; |
5231 | } |
5232 | uip = vp->v_ubcinfo; |
5233 | |
5234 | struct cs_blob *existing = uip->cs_blob_supplement; |
5235 | if (existing != NULL) { |
5236 | if (tmp_blob.csb_hashtype == existing->csb_hashtype && |
5237 | memcmp(s1: tmp_blob.csb_cdhash, s2: existing->csb_cdhash, n: CS_CDHASH_LEN) == 0) { |
5238 | error = EAGAIN; // non-fatal |
5239 | } else { |
5240 | error = EALREADY; // fatal |
5241 | } |
5242 | |
5243 | vnode_unlock(vp); |
5244 | goto out; |
5245 | } |
5246 | |
5247 | /* mark this vnode's VM object as having "signed pages" */ |
5248 | kr = memory_object_signed(control: uip->ui_control, TRUE); |
5249 | if (kr != KERN_SUCCESS) { |
5250 | vnode_unlock(vp); |
5251 | error = ENOENT; |
5252 | goto out; |
5253 | } |
5254 | |
5255 | |
5256 | /* We still adjust statistics even for supplemental blobs, as they |
5257 | * consume memory just the same. */ |
5258 | ubc_cs_blob_adjust_statistics(blob: &tmp_blob); |
5259 | /* Unlike regular cs_blobs, we only ever support one supplement. */ |
5260 | tmp_blob.csb_next = NULL; |
5261 | zalloc_ro_update_elem(ZONE_ID_CS_BLOB, blob_ro, &tmp_blob); |
5262 | |
5263 | os_atomic_thread_fence(seq_cst); // Fence to prevent reordering here |
5264 | uip->cs_blob_supplement = blob_ro; |
5265 | |
5266 | /* Make sure to reload pointer from uip to double check */ |
5267 | if (__improbable(uip->cs_blob_supplement->csb_next)) { |
5268 | panic("csb_next does not match expected NULL value" ); |
5269 | } |
5270 | |
5271 | vnode_unlock(vp); |
5272 | |
5273 | |
5274 | if (cs_debug > 1) { |
5275 | proc_t p; |
5276 | const char *name = vnode_getname_printable(vp); |
5277 | p = current_proc(); |
5278 | printf("CODE SIGNING: proc %d(%s) " |
5279 | "loaded supplemental signature for file (%s) " |
5280 | "range 0x%llx:0x%llx\n" , |
5281 | proc_getpid(p), p->p_comm, |
5282 | name, |
5283 | blob_ro->csb_base_offset + blob_ro->csb_start_offset, |
5284 | blob_ro->csb_base_offset + blob_ro->csb_end_offset); |
5285 | vnode_putname_printable(name); |
5286 | } |
5287 | |
5288 | if (ret_blob) { |
5289 | *ret_blob = blob_ro; |
5290 | } |
5291 | |
5292 | error = 0; // Success! |
5293 | out: |
5294 | if (error) { |
5295 | if (cs_debug) { |
5296 | printf("ubc_cs_blob_add_supplement[pid: %d]: error = %d\n" , proc_getpid(current_proc()), error); |
5297 | } |
5298 | |
5299 | cs_blob_cleanup(blob: &tmp_blob); |
5300 | if (blob_ro) { |
5301 | zfree_ro(ZONE_ID_CS_BLOB, blob_ro); |
5302 | } |
5303 | } |
5304 | |
5305 | if (error == EAGAIN) { |
5306 | /* We were asked to add an existing blob. |
5307 | * We cleaned up and ignore the attempt. */ |
5308 | error = 0; |
5309 | } |
5310 | |
5311 | return error; |
5312 | } |
5313 | #endif |
5314 | |
5315 | |
5316 | |
5317 | void |
5318 | csvnode_print_debug(struct vnode *vp) |
5319 | { |
5320 | const char *name = NULL; |
5321 | struct ubc_info *uip; |
5322 | struct cs_blob *blob; |
5323 | |
5324 | name = vnode_getname_printable(vp); |
5325 | if (name) { |
5326 | printf("csvnode: name: %s\n" , name); |
5327 | vnode_putname_printable(name); |
5328 | } |
5329 | |
5330 | vnode_lock_spin(vp); |
5331 | |
5332 | if (!UBCINFOEXISTS(vp)) { |
5333 | blob = NULL; |
5334 | goto out; |
5335 | } |
5336 | |
5337 | uip = vp->v_ubcinfo; |
5338 | for (blob = uip->cs_blobs; blob != NULL; blob = blob->csb_next) { |
5339 | printf("csvnode: range: %lu -> %lu flags: 0x%08x platform: %s path: %s team: %s\n" , |
5340 | (unsigned long)blob->csb_start_offset, |
5341 | (unsigned long)blob->csb_end_offset, |
5342 | blob->csb_flags, |
5343 | blob->csb_platform_binary ? "yes" : "no" , |
5344 | blob->csb_platform_path ? "yes" : "no" , |
5345 | blob->csb_teamid ? blob->csb_teamid : "<NO-TEAM>" ); |
5346 | } |
5347 | |
5348 | out: |
5349 | vnode_unlock(vp); |
5350 | } |
5351 | |
5352 | #if CONFIG_SUPPLEMENTAL_SIGNATURES |
5353 | struct cs_blob * |
5354 | ubc_cs_blob_get_supplement( |
5355 | struct vnode *vp, |
5356 | off_t offset) |
5357 | { |
5358 | struct cs_blob *blob; |
5359 | off_t offset_in_blob; |
5360 | |
5361 | vnode_lock_spin(vp); |
5362 | |
5363 | if (!UBCINFOEXISTS(vp)) { |
5364 | blob = NULL; |
5365 | goto out; |
5366 | } |
5367 | |
5368 | blob = vp->v_ubcinfo->cs_blob_supplement; |
5369 | |
5370 | if (blob == NULL) { |
5371 | // no supplemental blob |
5372 | goto out; |
5373 | } |
5374 | |
5375 | |
5376 | if (offset != -1) { |
5377 | offset_in_blob = offset - blob->csb_base_offset; |
5378 | if (offset_in_blob < blob->csb_start_offset || offset_in_blob >= blob->csb_end_offset) { |
5379 | // not actually covered by this blob |
5380 | blob = NULL; |
5381 | } |
5382 | } |
5383 | |
5384 | out: |
5385 | vnode_unlock(vp); |
5386 | |
5387 | return blob; |
5388 | } |
5389 | #endif |
5390 | |
5391 | struct cs_blob * |
5392 | ubc_cs_blob_get( |
5393 | struct vnode *vp, |
5394 | cpu_type_t cputype, |
5395 | cpu_subtype_t cpusubtype, |
5396 | off_t offset) |
5397 | { |
5398 | struct cs_blob *blob; |
5399 | off_t offset_in_blob; |
5400 | |
5401 | vnode_lock_spin(vp); |
5402 | |
5403 | if (!UBCINFOEXISTS(vp)) { |
5404 | blob = NULL; |
5405 | goto out; |
5406 | } |
5407 | |
5408 | for (blob = ubc_get_cs_blobs(vp); |
5409 | blob != NULL; |
5410 | blob = blob->csb_next) { |
5411 | if (cputype != -1 && blob->csb_cpu_type == cputype && (cpusubtype == -1 || blob->csb_cpu_subtype == (cpusubtype & ~CPU_SUBTYPE_MASK))) { |
5412 | break; |
5413 | } |
5414 | if (offset != -1) { |
5415 | offset_in_blob = offset - blob->csb_base_offset; |
5416 | if (offset_in_blob >= blob->csb_start_offset && |
5417 | offset_in_blob < blob->csb_end_offset) { |
5418 | /* our offset is covered by this blob */ |
5419 | break; |
5420 | } |
5421 | } |
5422 | } |
5423 | |
5424 | out: |
5425 | vnode_unlock(vp); |
5426 | |
5427 | return blob; |
5428 | } |
5429 | |
5430 | void |
5431 | ubc_cs_free_and_vnode_unlock( |
5432 | vnode_t vp) |
5433 | { |
5434 | struct ubc_info *uip = vp->v_ubcinfo; |
5435 | struct cs_blob *cs_blobs, *blob, *next_blob; |
5436 | |
5437 | if (!(uip->ui_flags & UI_CSBLOBINVALID)) { |
5438 | vnode_unlock(vp); |
5439 | return; |
5440 | } |
5441 | |
5442 | uip->ui_flags &= ~UI_CSBLOBINVALID; |
5443 | |
5444 | cs_blobs = uip->cs_blobs; |
5445 | uip->cs_blobs = NULL; |
5446 | |
5447 | #if CHECK_CS_VALIDATION_BITMAP |
5448 | ubc_cs_validation_bitmap_deallocate( uip ); |
5449 | #endif |
5450 | |
5451 | #if CONFIG_SUPPLEMENTAL_SIGNATURES |
5452 | struct cs_blob *cs_blob_supplement = uip->cs_blob_supplement; |
5453 | uip->cs_blob_supplement = NULL; |
5454 | #endif |
5455 | |
5456 | vnode_unlock(vp); |
5457 | |
5458 | for (blob = cs_blobs; |
5459 | blob != NULL; |
5460 | blob = next_blob) { |
5461 | next_blob = blob->csb_next; |
5462 | os_atomic_add(&cs_blob_count, -1, relaxed); |
5463 | os_atomic_add(&cs_blob_size, -blob->csb_mem_size, relaxed); |
5464 | cs_blob_ro_free(blob); |
5465 | } |
5466 | |
5467 | #if CONFIG_SUPPLEMENTAL_SIGNATURES |
5468 | if (cs_blob_supplement != NULL) { |
5469 | os_atomic_add(&cs_blob_count, -1, relaxed); |
5470 | os_atomic_add(&cs_blob_size, -cs_blob_supplement->csb_mem_size, relaxed); |
5471 | cs_blob_supplement_free(blob: cs_blob_supplement); |
5472 | } |
5473 | #endif |
5474 | } |
5475 | |
5476 | static void |
5477 | ubc_cs_free( |
5478 | struct ubc_info *uip) |
5479 | { |
5480 | struct cs_blob *blob, *next_blob; |
5481 | |
5482 | for (blob = uip->cs_blobs; |
5483 | blob != NULL; |
5484 | blob = next_blob) { |
5485 | next_blob = blob->csb_next; |
5486 | os_atomic_add(&cs_blob_count, -1, relaxed); |
5487 | os_atomic_add(&cs_blob_size, -blob->csb_mem_size, relaxed); |
5488 | cs_blob_ro_free(blob); |
5489 | } |
5490 | #if CHECK_CS_VALIDATION_BITMAP |
5491 | ubc_cs_validation_bitmap_deallocate( uip ); |
5492 | #endif |
5493 | uip->cs_blobs = NULL; |
5494 | #if CONFIG_SUPPLEMENTAL_SIGNATURES |
5495 | if (uip->cs_blob_supplement != NULL) { |
5496 | blob = uip->cs_blob_supplement; |
5497 | os_atomic_add(&cs_blob_count, -1, relaxed); |
5498 | os_atomic_add(&cs_blob_size, -blob->csb_mem_size, relaxed); |
5499 | cs_blob_supplement_free(blob: uip->cs_blob_supplement); |
5500 | uip->cs_blob_supplement = NULL; |
5501 | } |
5502 | #endif |
5503 | } |
5504 | |
5505 | /* check cs blob generation on vnode |
5506 | * returns: |
5507 | * 0 : Success, the cs_blob attached is current |
5508 | * ENEEDAUTH : Generation count mismatch. Needs authentication again. |
5509 | */ |
5510 | int |
5511 | ubc_cs_generation_check( |
5512 | struct vnode *vp) |
5513 | { |
5514 | int retval = ENEEDAUTH; |
5515 | |
5516 | vnode_lock_spin(vp); |
5517 | |
5518 | if (UBCINFOEXISTS(vp) && vp->v_ubcinfo->cs_add_gen == cs_blob_generation_count) { |
5519 | retval = 0; |
5520 | } |
5521 | |
5522 | vnode_unlock(vp); |
5523 | return retval; |
5524 | } |
5525 | |
5526 | int |
5527 | ubc_cs_blob_revalidate( |
5528 | struct vnode *vp, |
5529 | struct cs_blob *blob, |
5530 | struct image_params *imgp, |
5531 | int flags, |
5532 | uint32_t platform |
5533 | ) |
5534 | { |
5535 | int error = 0; |
5536 | const CS_CodeDirectory *cd = NULL; |
5537 | const CS_GenericBlob *entitlements = NULL; |
5538 | const CS_GenericBlob *der_entitlements = NULL; |
5539 | size_t size; |
5540 | assert(vp != NULL); |
5541 | assert(blob != NULL); |
5542 | |
5543 | if ((blob->csb_flags & CS_VALID) == 0) { |
5544 | // If the blob attached to the vnode was invalidated, don't try to revalidate it |
5545 | // Blob invalidation only occurs when the file that the blob is attached to is |
5546 | // opened for writing, giving us a signal that the file is modified. |
5547 | printf("CODESIGNING: can not re-validate a previously invalidated blob, reboot or create a new file.\n" ); |
5548 | error = EPERM; |
5549 | goto out; |
5550 | } |
5551 | |
5552 | size = blob->csb_mem_size; |
5553 | error = cs_validate_csblob(addr: (const uint8_t *)blob->csb_mem_kaddr, |
5554 | blob_size: size, rcd: &cd, rentitlements: &entitlements, rder_entitlements: &der_entitlements); |
5555 | if (error) { |
5556 | if (cs_debug) { |
5557 | printf("CODESIGNING: csblob invalid: %d\n" , error); |
5558 | } |
5559 | goto out; |
5560 | } |
5561 | |
5562 | unsigned int cs_flags = (ntohl(cd->flags) & CS_ALLOWED_MACHO) | CS_VALID; |
5563 | unsigned int signer_type = CS_SIGNER_TYPE_UNKNOWN; |
5564 | |
5565 | if (blob->csb_reconstituted) { |
5566 | /* |
5567 | * Code signatures that have been modified after validation |
5568 | * cannot be revalidated inline from their in-memory blob. |
5569 | * |
5570 | * That's okay, though, because the only path left that relies |
5571 | * on revalidation of existing in-memory blobs is the legacy |
5572 | * detached signature database path, which only exists on macOS, |
5573 | * which does not do reconstitution of any kind. |
5574 | */ |
5575 | if (cs_debug) { |
5576 | printf("CODESIGNING: revalidate: not inline revalidating reconstituted signature.\n" ); |
5577 | } |
5578 | |
5579 | /* |
5580 | * EAGAIN tells the caller that they may reread the code |
5581 | * signature and try attaching it again, which is the same |
5582 | * thing they would do if there was no cs_blob yet in the |
5583 | * first place. |
5584 | * |
5585 | * Conveniently, after ubc_cs_blob_add did a successful |
5586 | * validation, it will detect that a matching cs_blob (cdhash, |
5587 | * offset, arch etc.) already exists, and return success |
5588 | * without re-adding a cs_blob to the vnode. |
5589 | */ |
5590 | return EAGAIN; |
5591 | } |
5592 | |
5593 | /* callout to mac_vnode_check_signature */ |
5594 | #if CONFIG_MACF |
5595 | error = mac_vnode_check_signature(vp, cs_blob: blob, imgp, cs_flags: &cs_flags, signer_type: &signer_type, flags, platform); |
5596 | if (cs_debug && error) { |
5597 | printf("revalidate: check_signature[pid: %d], error = %d\n" , proc_getpid(current_proc()), error); |
5598 | } |
5599 | #else |
5600 | (void)flags; |
5601 | (void)signer_type; |
5602 | #endif |
5603 | |
5604 | /* update generation number if success */ |
5605 | vnode_lock_spin(vp); |
5606 | struct cs_signer_info signer_info = { |
5607 | .csb_flags = cs_flags, |
5608 | .csb_signer_type = signer_type |
5609 | }; |
5610 | zalloc_ro_update_field(ZONE_ID_CS_BLOB, blob, csb_signer_info, &signer_info); |
5611 | if (UBCINFOEXISTS(vp)) { |
5612 | if (error == 0) { |
5613 | vp->v_ubcinfo->cs_add_gen = cs_blob_generation_count; |
5614 | } else { |
5615 | vp->v_ubcinfo->cs_add_gen = 0; |
5616 | } |
5617 | } |
5618 | |
5619 | vnode_unlock(vp); |
5620 | |
5621 | out: |
5622 | return error; |
5623 | } |
5624 | |
5625 | void |
5626 | cs_blob_reset_cache() |
5627 | { |
5628 | /* incrementing odd no by 2 makes sure '0' is never reached. */ |
5629 | OSAddAtomic(+2, &cs_blob_generation_count); |
5630 | printf("Reseting cs_blob cache from all vnodes. \n" ); |
5631 | } |
5632 | |
5633 | struct cs_blob * |
5634 | ubc_get_cs_blobs( |
5635 | struct vnode *vp) |
5636 | { |
5637 | struct ubc_info *uip; |
5638 | struct cs_blob *blobs; |
5639 | |
5640 | /* |
5641 | * No need to take the vnode lock here. The caller must be holding |
5642 | * a reference on the vnode (via a VM mapping or open file descriptor), |
5643 | * so the vnode will not go away. The ubc_info stays until the vnode |
5644 | * goes away. And we only modify "blobs" by adding to the head of the |
5645 | * list. |
5646 | * The ubc_info could go away entirely if the vnode gets reclaimed as |
5647 | * part of a forced unmount. In the case of a code-signature validation |
5648 | * during a page fault, the "paging_in_progress" reference on the VM |
5649 | * object guarantess that the vnode pager (and the ubc_info) won't go |
5650 | * away during the fault. |
5651 | * Other callers need to protect against vnode reclaim by holding the |
5652 | * vnode lock, for example. |
5653 | */ |
5654 | |
5655 | if (!UBCINFOEXISTS(vp)) { |
5656 | blobs = NULL; |
5657 | goto out; |
5658 | } |
5659 | |
5660 | uip = vp->v_ubcinfo; |
5661 | blobs = uip->cs_blobs; |
5662 | if (blobs != NULL) { |
5663 | cs_blob_require(blob: blobs, vp); |
5664 | } |
5665 | |
5666 | out: |
5667 | return blobs; |
5668 | } |
5669 | |
5670 | #if CONFIG_SUPPLEMENTAL_SIGNATURES |
5671 | struct cs_blob * |
5672 | ubc_get_cs_supplement( |
5673 | struct vnode *vp) |
5674 | { |
5675 | struct ubc_info *uip; |
5676 | struct cs_blob *blob; |
5677 | |
5678 | /* |
5679 | * No need to take the vnode lock here. The caller must be holding |
5680 | * a reference on the vnode (via a VM mapping or open file descriptor), |
5681 | * so the vnode will not go away. The ubc_info stays until the vnode |
5682 | * goes away. |
5683 | * The ubc_info could go away entirely if the vnode gets reclaimed as |
5684 | * part of a forced unmount. In the case of a code-signature validation |
5685 | * during a page fault, the "paging_in_progress" reference on the VM |
5686 | * object guarantess that the vnode pager (and the ubc_info) won't go |
5687 | * away during the fault. |
5688 | * Other callers need to protect against vnode reclaim by holding the |
5689 | * vnode lock, for example. |
5690 | */ |
5691 | |
5692 | if (!UBCINFOEXISTS(vp)) { |
5693 | blob = NULL; |
5694 | goto out; |
5695 | } |
5696 | |
5697 | uip = vp->v_ubcinfo; |
5698 | blob = uip->cs_blob_supplement; |
5699 | if (blob != NULL) { |
5700 | cs_blob_require(blob, vp); |
5701 | } |
5702 | |
5703 | out: |
5704 | return blob; |
5705 | } |
5706 | #endif |
5707 | |
5708 | |
5709 | void |
5710 | ubc_get_cs_mtime( |
5711 | struct vnode *vp, |
5712 | struct timespec *cs_mtime) |
5713 | { |
5714 | struct ubc_info *uip; |
5715 | |
5716 | if (!UBCINFOEXISTS(vp)) { |
5717 | cs_mtime->tv_sec = 0; |
5718 | cs_mtime->tv_nsec = 0; |
5719 | return; |
5720 | } |
5721 | |
5722 | uip = vp->v_ubcinfo; |
5723 | cs_mtime->tv_sec = uip->cs_mtime.tv_sec; |
5724 | cs_mtime->tv_nsec = uip->cs_mtime.tv_nsec; |
5725 | } |
5726 | |
5727 | unsigned long cs_validate_page_no_hash = 0; |
5728 | unsigned long cs_validate_page_bad_hash = 0; |
5729 | static boolean_t |
5730 | cs_validate_hash( |
5731 | struct cs_blob *blobs, |
5732 | memory_object_t , |
5733 | memory_object_offset_t page_offset, |
5734 | const void *data, |
5735 | vm_size_t *bytes_processed, |
5736 | unsigned *tainted) |
5737 | { |
5738 | union cs_hash_union mdctx; |
5739 | struct cs_hash const *hashtype = NULL; |
5740 | unsigned char actual_hash[CS_HASH_MAX_SIZE]; |
5741 | unsigned char expected_hash[CS_HASH_MAX_SIZE]; |
5742 | boolean_t found_hash; |
5743 | struct cs_blob *blob; |
5744 | const CS_CodeDirectory *cd; |
5745 | const unsigned char *hash; |
5746 | boolean_t validated; |
5747 | off_t offset; /* page offset in the file */ |
5748 | size_t size; |
5749 | off_t codeLimit = 0; |
5750 | const char *lower_bound, *upper_bound; |
5751 | vm_offset_t kaddr, blob_addr; |
5752 | |
5753 | /* retrieve the expected hash */ |
5754 | found_hash = FALSE; |
5755 | |
5756 | for (blob = blobs; |
5757 | blob != NULL; |
5758 | blob = blob->csb_next) { |
5759 | offset = page_offset - blob->csb_base_offset; |
5760 | if (offset < blob->csb_start_offset || |
5761 | offset >= blob->csb_end_offset) { |
5762 | /* our page is not covered by this blob */ |
5763 | continue; |
5764 | } |
5765 | |
5766 | /* blob data has been released */ |
5767 | kaddr = (vm_offset_t)blob->csb_mem_kaddr; |
5768 | if (kaddr == 0) { |
5769 | continue; |
5770 | } |
5771 | |
5772 | blob_addr = kaddr + blob->csb_mem_offset; |
5773 | lower_bound = CAST_DOWN(char *, blob_addr); |
5774 | upper_bound = lower_bound + blob->csb_mem_size; |
5775 | |
5776 | cd = blob->csb_cd; |
5777 | if (cd != NULL) { |
5778 | /* all CD's that have been injected is already validated */ |
5779 | |
5780 | hashtype = blob->csb_hashtype; |
5781 | if (hashtype == NULL) { |
5782 | panic("unknown hash type ?" ); |
5783 | } |
5784 | if (hashtype->cs_digest_size > sizeof(actual_hash)) { |
5785 | panic("hash size too large" ); |
5786 | } |
5787 | if (offset & ((1U << blob->csb_hash_pageshift) - 1)) { |
5788 | panic("offset not aligned to cshash boundary" ); |
5789 | } |
5790 | |
5791 | codeLimit = ntohl(cd->codeLimit); |
5792 | |
5793 | hash = hashes(cd, page: (uint32_t)(offset >> blob->csb_hash_pageshift), |
5794 | hash_len: hashtype->cs_size, |
5795 | lower_bound, upper_bound); |
5796 | if (hash != NULL) { |
5797 | bcopy(src: hash, dst: expected_hash, n: hashtype->cs_size); |
5798 | found_hash = TRUE; |
5799 | } |
5800 | |
5801 | break; |
5802 | } |
5803 | } |
5804 | |
5805 | if (found_hash == FALSE) { |
5806 | /* |
5807 | * We can't verify this page because there is no signature |
5808 | * for it (yet). It's possible that this part of the object |
5809 | * is not signed, or that signatures for that part have not |
5810 | * been loaded yet. |
5811 | * Report that the page has not been validated and let the |
5812 | * caller decide if it wants to accept it or not. |
5813 | */ |
5814 | cs_validate_page_no_hash++; |
5815 | if (cs_debug > 1) { |
5816 | printf("CODE SIGNING: cs_validate_page: " |
5817 | "mobj %p off 0x%llx: no hash to validate !?\n" , |
5818 | pager, page_offset); |
5819 | } |
5820 | validated = FALSE; |
5821 | *tainted = 0; |
5822 | } else { |
5823 | *tainted = 0; |
5824 | |
5825 | size = (1U << blob->csb_hash_pageshift); |
5826 | *bytes_processed = size; |
5827 | |
5828 | const uint32_t *asha1, *esha1; |
5829 | if ((off_t)(offset + size) > codeLimit) { |
5830 | /* partial page at end of segment */ |
5831 | assert(offset < codeLimit); |
5832 | size = (size_t) (codeLimit & (size - 1)); |
5833 | *tainted |= CS_VALIDATE_NX; |
5834 | } |
5835 | |
5836 | hashtype->cs_init(&mdctx); |
5837 | |
5838 | if (blob->csb_hash_firstlevel_pageshift) { |
5839 | const unsigned char *partial_data = (const unsigned char *)data; |
5840 | size_t i; |
5841 | for (i = 0; i < size;) { |
5842 | union cs_hash_union partialctx; |
5843 | unsigned char partial_digest[CS_HASH_MAX_SIZE]; |
5844 | size_t partial_size = MIN(size - i, (1U << blob->csb_hash_firstlevel_pageshift)); |
5845 | |
5846 | hashtype->cs_init(&partialctx); |
5847 | hashtype->cs_update(&partialctx, partial_data, partial_size); |
5848 | hashtype->cs_final(partial_digest, &partialctx); |
5849 | |
5850 | /* Update cumulative multi-level hash */ |
5851 | hashtype->cs_update(&mdctx, partial_digest, hashtype->cs_size); |
5852 | partial_data = partial_data + partial_size; |
5853 | i += partial_size; |
5854 | } |
5855 | } else { |
5856 | hashtype->cs_update(&mdctx, data, size); |
5857 | } |
5858 | hashtype->cs_final(actual_hash, &mdctx); |
5859 | |
5860 | asha1 = (const uint32_t *) actual_hash; |
5861 | esha1 = (const uint32_t *) expected_hash; |
5862 | |
5863 | if (bcmp(s1: expected_hash, s2: actual_hash, n: hashtype->cs_size) != 0) { |
5864 | if (cs_debug) { |
5865 | printf("CODE SIGNING: cs_validate_page: " |
5866 | "mobj %p off 0x%llx size 0x%lx: " |
5867 | "actual [0x%x 0x%x 0x%x 0x%x 0x%x] != " |
5868 | "expected [0x%x 0x%x 0x%x 0x%x 0x%x]\n" , |
5869 | pager, page_offset, size, |
5870 | asha1[0], asha1[1], asha1[2], |
5871 | asha1[3], asha1[4], |
5872 | esha1[0], esha1[1], esha1[2], |
5873 | esha1[3], esha1[4]); |
5874 | } |
5875 | cs_validate_page_bad_hash++; |
5876 | *tainted |= CS_VALIDATE_TAINTED; |
5877 | } else { |
5878 | if (cs_debug > 10) { |
5879 | printf("CODE SIGNING: cs_validate_page: " |
5880 | "mobj %p off 0x%llx size 0x%lx: " |
5881 | "SHA1 OK\n" , |
5882 | pager, page_offset, size); |
5883 | } |
5884 | } |
5885 | validated = TRUE; |
5886 | } |
5887 | |
5888 | return validated; |
5889 | } |
5890 | |
5891 | boolean_t |
5892 | cs_validate_range( |
5893 | struct vnode *vp, |
5894 | memory_object_t , |
5895 | memory_object_offset_t page_offset, |
5896 | const void *data, |
5897 | vm_size_t dsize, |
5898 | unsigned *tainted) |
5899 | { |
5900 | vm_size_t offset_in_range; |
5901 | boolean_t all_subranges_validated = TRUE; /* turn false if any subrange fails */ |
5902 | |
5903 | struct cs_blob *blobs = ubc_get_cs_blobs(vp); |
5904 | |
5905 | #if CONFIG_SUPPLEMENTAL_SIGNATURES |
5906 | if (blobs == NULL && proc_is_translated(current_proc())) { |
5907 | struct cs_blob *supp = ubc_get_cs_supplement(vp); |
5908 | |
5909 | if (supp != NULL) { |
5910 | blobs = supp; |
5911 | } else { |
5912 | return FALSE; |
5913 | } |
5914 | } |
5915 | #endif |
5916 | |
5917 | #if DEVELOPMENT || DEBUG |
5918 | code_signing_config_t cs_config = 0; |
5919 | |
5920 | /* |
5921 | * This exemption is specifically useful for systems which want to avoid paying |
5922 | * the cost of verifying the integrity of pages, since that is done by computing |
5923 | * hashes, which can take some time. |
5924 | */ |
5925 | code_signing_configuration(NULL, &cs_config); |
5926 | if (cs_config & CS_CONFIG_INTEGRITY_SKIP) { |
5927 | *tainted = 0; |
5928 | |
5929 | /* Return early to avoid paying the cost of hashing */ |
5930 | return true; |
5931 | } |
5932 | #endif |
5933 | |
5934 | *tainted = 0; |
5935 | |
5936 | for (offset_in_range = 0; |
5937 | offset_in_range < dsize; |
5938 | /* offset_in_range updated based on bytes processed */) { |
5939 | unsigned subrange_tainted = 0; |
5940 | boolean_t subrange_validated; |
5941 | vm_size_t bytes_processed = 0; |
5942 | |
5943 | subrange_validated = cs_validate_hash(blobs, |
5944 | pager, |
5945 | page_offset: page_offset + offset_in_range, |
5946 | data: (const void *)((const char *)data + offset_in_range), |
5947 | bytes_processed: &bytes_processed, |
5948 | tainted: &subrange_tainted); |
5949 | |
5950 | *tainted |= subrange_tainted; |
5951 | |
5952 | if (bytes_processed == 0) { |
5953 | /* Cannote make forward progress, so return an error */ |
5954 | all_subranges_validated = FALSE; |
5955 | break; |
5956 | } else if (subrange_validated == FALSE) { |
5957 | all_subranges_validated = FALSE; |
5958 | /* Keep going to detect other types of failures in subranges */ |
5959 | } |
5960 | |
5961 | offset_in_range += bytes_processed; |
5962 | } |
5963 | |
5964 | return all_subranges_validated; |
5965 | } |
5966 | |
5967 | void |
5968 | cs_validate_page( |
5969 | struct vnode *vp, |
5970 | memory_object_t , |
5971 | memory_object_offset_t page_offset, |
5972 | const void *data, |
5973 | int *validated_p, |
5974 | int *tainted_p, |
5975 | int *nx_p) |
5976 | { |
5977 | vm_size_t offset_in_page; |
5978 | struct cs_blob *blobs; |
5979 | |
5980 | blobs = ubc_get_cs_blobs(vp); |
5981 | |
5982 | #if CONFIG_SUPPLEMENTAL_SIGNATURES |
5983 | if (blobs == NULL && proc_is_translated(current_proc())) { |
5984 | struct cs_blob *supp = ubc_get_cs_supplement(vp); |
5985 | |
5986 | if (supp != NULL) { |
5987 | blobs = supp; |
5988 | } |
5989 | } |
5990 | #endif |
5991 | |
5992 | #if DEVELOPMENT || DEBUG |
5993 | code_signing_config_t cs_config = 0; |
5994 | |
5995 | /* |
5996 | * This exemption is specifically useful for systems which want to avoid paying |
5997 | * the cost of verifying the integrity of pages, since that is done by computing |
5998 | * hashes, which can take some time. |
5999 | */ |
6000 | code_signing_configuration(NULL, &cs_config); |
6001 | if (cs_config & CS_CONFIG_INTEGRITY_SKIP) { |
6002 | *validated_p = VMP_CS_ALL_TRUE; |
6003 | *tainted_p = VMP_CS_ALL_FALSE; |
6004 | *nx_p = VMP_CS_ALL_FALSE; |
6005 | |
6006 | /* Return early to avoid paying the cost of hashing */ |
6007 | return; |
6008 | } |
6009 | #endif |
6010 | |
6011 | *validated_p = VMP_CS_ALL_FALSE; |
6012 | *tainted_p = VMP_CS_ALL_FALSE; |
6013 | *nx_p = VMP_CS_ALL_FALSE; |
6014 | |
6015 | for (offset_in_page = 0; |
6016 | offset_in_page < PAGE_SIZE; |
6017 | /* offset_in_page updated based on bytes processed */) { |
6018 | unsigned subrange_tainted = 0; |
6019 | boolean_t subrange_validated; |
6020 | vm_size_t bytes_processed = 0; |
6021 | int sub_bit; |
6022 | |
6023 | subrange_validated = cs_validate_hash(blobs, |
6024 | pager, |
6025 | page_offset: page_offset + offset_in_page, |
6026 | data: (const void *)((const char *)data + offset_in_page), |
6027 | bytes_processed: &bytes_processed, |
6028 | tainted: &subrange_tainted); |
6029 | |
6030 | if (bytes_processed == 0) { |
6031 | /* 4k chunk not code-signed: try next one */ |
6032 | offset_in_page += FOURK_PAGE_SIZE; |
6033 | continue; |
6034 | } |
6035 | if (offset_in_page == 0 && |
6036 | bytes_processed > PAGE_SIZE - FOURK_PAGE_SIZE) { |
6037 | /* all processed: no 4k granularity */ |
6038 | if (subrange_validated) { |
6039 | *validated_p = VMP_CS_ALL_TRUE; |
6040 | } |
6041 | if (subrange_tainted & CS_VALIDATE_TAINTED) { |
6042 | *tainted_p = VMP_CS_ALL_TRUE; |
6043 | } |
6044 | if (subrange_tainted & CS_VALIDATE_NX) { |
6045 | *nx_p = VMP_CS_ALL_TRUE; |
6046 | } |
6047 | break; |
6048 | } |
6049 | /* we only handle 4k or 16k code-signing granularity... */ |
6050 | assertf(bytes_processed <= FOURK_PAGE_SIZE, |
6051 | "vp %p blobs %p offset 0x%llx + 0x%llx bytes_processed 0x%llx\n" , |
6052 | vp, blobs, (uint64_t)page_offset, |
6053 | (uint64_t)offset_in_page, (uint64_t)bytes_processed); |
6054 | sub_bit = 1 << (offset_in_page >> FOURK_PAGE_SHIFT); |
6055 | if (subrange_validated) { |
6056 | *validated_p |= sub_bit; |
6057 | } |
6058 | if (subrange_tainted & CS_VALIDATE_TAINTED) { |
6059 | *tainted_p |= sub_bit; |
6060 | } |
6061 | if (subrange_tainted & CS_VALIDATE_NX) { |
6062 | *nx_p |= sub_bit; |
6063 | } |
6064 | /* go to next 4k chunk */ |
6065 | offset_in_page += FOURK_PAGE_SIZE; |
6066 | } |
6067 | |
6068 | return; |
6069 | } |
6070 | |
6071 | int |
6072 | ubc_cs_getcdhash( |
6073 | vnode_t vp, |
6074 | off_t offset, |
6075 | unsigned char *cdhash) |
6076 | { |
6077 | struct cs_blob *blobs, *blob; |
6078 | off_t rel_offset; |
6079 | int ret; |
6080 | |
6081 | vnode_lock(vp); |
6082 | |
6083 | blobs = ubc_get_cs_blobs(vp); |
6084 | for (blob = blobs; |
6085 | blob != NULL; |
6086 | blob = blob->csb_next) { |
6087 | /* compute offset relative to this blob */ |
6088 | rel_offset = offset - blob->csb_base_offset; |
6089 | if (rel_offset >= blob->csb_start_offset && |
6090 | rel_offset < blob->csb_end_offset) { |
6091 | /* this blob does cover our "offset" ! */ |
6092 | break; |
6093 | } |
6094 | } |
6095 | |
6096 | if (blob == NULL) { |
6097 | /* we didn't find a blob covering "offset" */ |
6098 | ret = EBADEXEC; /* XXX any better error ? */ |
6099 | } else { |
6100 | /* get the SHA1 hash of that blob */ |
6101 | bcopy(src: blob->csb_cdhash, dst: cdhash, n: sizeof(blob->csb_cdhash)); |
6102 | ret = 0; |
6103 | } |
6104 | |
6105 | vnode_unlock(vp); |
6106 | |
6107 | return ret; |
6108 | } |
6109 | |
6110 | boolean_t |
6111 | ubc_cs_is_range_codesigned( |
6112 | vnode_t vp, |
6113 | mach_vm_offset_t start, |
6114 | mach_vm_size_t size) |
6115 | { |
6116 | struct cs_blob *csblob; |
6117 | mach_vm_offset_t blob_start; |
6118 | mach_vm_offset_t blob_end; |
6119 | |
6120 | if (vp == NULL) { |
6121 | /* no file: no code signature */ |
6122 | return FALSE; |
6123 | } |
6124 | if (size == 0) { |
6125 | /* no range: no code signature */ |
6126 | return FALSE; |
6127 | } |
6128 | if (start + size < start) { |
6129 | /* overflow */ |
6130 | return FALSE; |
6131 | } |
6132 | |
6133 | csblob = ubc_cs_blob_get(vp, cputype: -1, cpusubtype: -1, offset: start); |
6134 | if (csblob == NULL) { |
6135 | return FALSE; |
6136 | } |
6137 | |
6138 | /* |
6139 | * We currently check if the range is covered by a single blob, |
6140 | * which should always be the case for the dyld shared cache. |
6141 | * If we ever want to make this routine handle other cases, we |
6142 | * would have to iterate if the blob does not cover the full range. |
6143 | */ |
6144 | blob_start = (mach_vm_offset_t) (csblob->csb_base_offset + |
6145 | csblob->csb_start_offset); |
6146 | blob_end = (mach_vm_offset_t) (csblob->csb_base_offset + |
6147 | csblob->csb_end_offset); |
6148 | if (blob_start > start || blob_end < (start + size)) { |
6149 | /* range not fully covered by this code-signing blob */ |
6150 | return FALSE; |
6151 | } |
6152 | |
6153 | return TRUE; |
6154 | } |
6155 | |
6156 | #if CHECK_CS_VALIDATION_BITMAP |
6157 | #define stob(s) (((atop_64(round_page_64(s))) + 07) >> 3) |
6158 | extern boolean_t root_fs_upgrade_try; |
6159 | |
6160 | /* |
6161 | * Should we use the code-sign bitmap to avoid repeated code-sign validation? |
6162 | * Depends: |
6163 | * a) Is the target vnode on the root filesystem? |
6164 | * b) Has someone tried to mount the root filesystem read-write? |
6165 | * If answers are (a) yes AND (b) no, then we can use the bitmap. |
6166 | */ |
6167 | #define USE_CODE_SIGN_BITMAP(vp) ( (vp != NULL) && (vp->v_mount != NULL) && (vp->v_mount->mnt_flag & MNT_ROOTFS) && !root_fs_upgrade_try) |
6168 | kern_return_t |
6169 | ubc_cs_validation_bitmap_allocate( |
6170 | vnode_t vp) |
6171 | { |
6172 | kern_return_t kr = KERN_SUCCESS; |
6173 | struct ubc_info *uip; |
6174 | char *target_bitmap; |
6175 | vm_object_size_t bitmap_size; |
6176 | |
6177 | if (!USE_CODE_SIGN_BITMAP(vp) || (!UBCINFOEXISTS(vp))) { |
6178 | kr = KERN_INVALID_ARGUMENT; |
6179 | } else { |
6180 | uip = vp->v_ubcinfo; |
6181 | |
6182 | if (uip->cs_valid_bitmap == NULL) { |
6183 | bitmap_size = stob(uip->ui_size); |
6184 | target_bitmap = (char*) kalloc_data((vm_size_t)bitmap_size, Z_WAITOK | Z_ZERO); |
6185 | if (target_bitmap == 0) { |
6186 | kr = KERN_NO_SPACE; |
6187 | } else { |
6188 | kr = KERN_SUCCESS; |
6189 | } |
6190 | if (kr == KERN_SUCCESS) { |
6191 | uip->cs_valid_bitmap = (void*)target_bitmap; |
6192 | uip->cs_valid_bitmap_size = bitmap_size; |
6193 | } |
6194 | } |
6195 | } |
6196 | return kr; |
6197 | } |
6198 | |
6199 | kern_return_t |
6200 | ubc_cs_check_validation_bitmap( |
6201 | vnode_t vp, |
6202 | memory_object_offset_t offset, |
6203 | int optype) |
6204 | { |
6205 | kern_return_t kr = KERN_SUCCESS; |
6206 | |
6207 | if (!USE_CODE_SIGN_BITMAP(vp) || !UBCINFOEXISTS(vp)) { |
6208 | kr = KERN_INVALID_ARGUMENT; |
6209 | } else { |
6210 | struct ubc_info *uip = vp->v_ubcinfo; |
6211 | char *target_bitmap = uip->cs_valid_bitmap; |
6212 | |
6213 | if (target_bitmap == NULL) { |
6214 | kr = KERN_INVALID_ARGUMENT; |
6215 | } else { |
6216 | uint64_t bit, byte; |
6217 | bit = atop_64( offset ); |
6218 | byte = bit >> 3; |
6219 | |
6220 | if (byte > uip->cs_valid_bitmap_size) { |
6221 | kr = KERN_INVALID_ARGUMENT; |
6222 | } else { |
6223 | if (optype == CS_BITMAP_SET) { |
6224 | target_bitmap[byte] |= (1 << (bit & 07)); |
6225 | kr = KERN_SUCCESS; |
6226 | } else if (optype == CS_BITMAP_CLEAR) { |
6227 | target_bitmap[byte] &= ~(1 << (bit & 07)); |
6228 | kr = KERN_SUCCESS; |
6229 | } else if (optype == CS_BITMAP_CHECK) { |
6230 | if (target_bitmap[byte] & (1 << (bit & 07))) { |
6231 | kr = KERN_SUCCESS; |
6232 | } else { |
6233 | kr = KERN_FAILURE; |
6234 | } |
6235 | } |
6236 | } |
6237 | } |
6238 | } |
6239 | return kr; |
6240 | } |
6241 | |
6242 | void |
6243 | ubc_cs_validation_bitmap_deallocate( |
6244 | struct ubc_info *uip) |
6245 | { |
6246 | if (uip->cs_valid_bitmap != NULL) { |
6247 | kfree_data(uip->cs_valid_bitmap, (vm_size_t)uip->cs_valid_bitmap_size); |
6248 | uip->cs_valid_bitmap = NULL; |
6249 | } |
6250 | } |
6251 | #else |
6252 | kern_return_t |
6253 | ubc_cs_validation_bitmap_allocate(__unused vnode_t vp) |
6254 | { |
6255 | return KERN_INVALID_ARGUMENT; |
6256 | } |
6257 | |
6258 | kern_return_t |
6259 | ubc_cs_check_validation_bitmap( |
6260 | __unused struct vnode *vp, |
6261 | __unused memory_object_offset_t offset, |
6262 | __unused int optype) |
6263 | { |
6264 | return KERN_INVALID_ARGUMENT; |
6265 | } |
6266 | |
6267 | void |
6268 | ubc_cs_validation_bitmap_deallocate(__unused struct ubc_info *uip) |
6269 | { |
6270 | return; |
6271 | } |
6272 | #endif /* CHECK_CS_VALIDATION_BITMAP */ |
6273 | |
6274 | #if CODE_SIGNING_MONITOR |
6275 | |
6276 | kern_return_t |
6277 | cs_associate_blob_with_mapping( |
6278 | void *pmap, |
6279 | vm_map_offset_t start, |
6280 | vm_map_size_t size, |
6281 | vm_object_offset_t offset, |
6282 | void *blobs_p) |
6283 | { |
6284 | off_t blob_start_offset, blob_end_offset; |
6285 | kern_return_t kr; |
6286 | struct cs_blob *blobs, *blob; |
6287 | vm_offset_t kaddr; |
6288 | void *monitor_sig_obj = NULL; |
6289 | |
6290 | if (csm_enabled() == false) { |
6291 | return KERN_NOT_SUPPORTED; |
6292 | } |
6293 | |
6294 | blobs = (struct cs_blob *)blobs_p; |
6295 | |
6296 | for (blob = blobs; |
6297 | blob != NULL; |
6298 | blob = blob->csb_next) { |
6299 | blob_start_offset = (blob->csb_base_offset + |
6300 | blob->csb_start_offset); |
6301 | blob_end_offset = (blob->csb_base_offset + |
6302 | blob->csb_end_offset); |
6303 | if ((off_t) offset < blob_start_offset || |
6304 | (off_t) offset >= blob_end_offset || |
6305 | (off_t) (offset + size) <= blob_start_offset || |
6306 | (off_t) (offset + size) > blob_end_offset) { |
6307 | continue; |
6308 | } |
6309 | |
6310 | kaddr = (vm_offset_t)blob->csb_mem_kaddr; |
6311 | if (kaddr == 0) { |
6312 | /* blob data has been released */ |
6313 | continue; |
6314 | } |
6315 | |
6316 | monitor_sig_obj = blob->csb_csm_obj; |
6317 | if (monitor_sig_obj == NULL) { |
6318 | continue; |
6319 | } |
6320 | |
6321 | break; |
6322 | } |
6323 | |
6324 | if (monitor_sig_obj != NULL) { |
6325 | vm_offset_t segment_offset = offset - blob_start_offset; |
6326 | kr = csm_associate_code_signature(pmap, monitor_sig_obj, start, size, segment_offset); |
6327 | } else { |
6328 | kr = KERN_CODESIGN_ERROR; |
6329 | } |
6330 | |
6331 | return kr; |
6332 | } |
6333 | |
6334 | #endif /* CODE_SIGNING_MONITOR */ |
6335 | |