1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24#include "qemu/osdep.h"
25#include "qapi/error.h"
26#include "qemu-common.h"
27#include "block/block_int.h"
28#include "qemu/bswap.h"
29#include "qemu/error-report.h"
30#include "qemu/module.h"
31#include "dmg.h"
32
33int (*dmg_uncompress_bz2)(char *next_in, unsigned int avail_in,
34 char *next_out, unsigned int avail_out);
35
36int (*dmg_uncompress_lzfse)(char *next_in, unsigned int avail_in,
37 char *next_out, unsigned int avail_out);
38
39enum {
40
41
42
43 DMG_LENGTHS_MAX = 64 * 1024 * 1024,
44 DMG_SECTORCOUNTS_MAX = DMG_LENGTHS_MAX / 512,
45};
46
47enum {
48
49 UDZE = 0,
50 UDRW,
51 UDIG,
52 UDCO = 0x80000004,
53 UDZO,
54 UDBZ,
55 ULFO,
56 UDCM = 0x7ffffffe,
57 UDLE = 0xffffffff
58};
59
60static int dmg_probe(const uint8_t *buf, int buf_size, const char *filename)
61{
62 int len;
63
64 if (!filename) {
65 return 0;
66 }
67
68 len = strlen(filename);
69 if (len > 4 && !strcmp(filename + len - 4, ".dmg")) {
70 return 2;
71 }
72 return 0;
73}
74
75static int read_uint64(BlockDriverState *bs, int64_t offset, uint64_t *result)
76{
77 uint64_t buffer;
78 int ret;
79
80 ret = bdrv_pread(bs->file, offset, &buffer, 8);
81 if (ret < 0) {
82 return ret;
83 }
84
85 *result = be64_to_cpu(buffer);
86 return 0;
87}
88
89static int read_uint32(BlockDriverState *bs, int64_t offset, uint32_t *result)
90{
91 uint32_t buffer;
92 int ret;
93
94 ret = bdrv_pread(bs->file, offset, &buffer, 4);
95 if (ret < 0) {
96 return ret;
97 }
98
99 *result = be32_to_cpu(buffer);
100 return 0;
101}
102
103static inline uint64_t buff_read_uint64(const uint8_t *buffer, int64_t offset)
104{
105 return be64_to_cpu(*(uint64_t *)&buffer[offset]);
106}
107
108static inline uint32_t buff_read_uint32(const uint8_t *buffer, int64_t offset)
109{
110 return be32_to_cpu(*(uint32_t *)&buffer[offset]);
111}
112
113
114
115
116static void update_max_chunk_size(BDRVDMGState *s, uint32_t chunk,
117 uint32_t *max_compressed_size,
118 uint32_t *max_sectors_per_chunk)
119{
120 uint32_t compressed_size = 0;
121 uint32_t uncompressed_sectors = 0;
122
123 switch (s->types[chunk]) {
124 case UDZO:
125 case UDBZ:
126 case ULFO:
127 compressed_size = s->lengths[chunk];
128 uncompressed_sectors = s->sectorcounts[chunk];
129 break;
130 case UDRW:
131 uncompressed_sectors = DIV_ROUND_UP(s->lengths[chunk], 512);
132 break;
133 case UDZE:
134 case UDIG:
135
136
137
138 break;
139 }
140
141 if (compressed_size > *max_compressed_size) {
142 *max_compressed_size = compressed_size;
143 }
144 if (uncompressed_sectors > *max_sectors_per_chunk) {
145 *max_sectors_per_chunk = uncompressed_sectors;
146 }
147}
148
149static int64_t dmg_find_koly_offset(BdrvChild *file, Error **errp)
150{
151 BlockDriverState *file_bs = file->bs;
152 int64_t length;
153 int64_t offset = 0;
154 uint8_t buffer[515];
155 int i, ret;
156
157
158
159
160
161
162 length = bdrv_getlength(file_bs);
163 if (length < 0) {
164 error_setg_errno(errp, -length,
165 "Failed to get file size while reading UDIF trailer");
166 return length;
167 } else if (length < 512) {
168 error_setg(errp, "dmg file must be at least 512 bytes long");
169 return -EINVAL;
170 }
171 if (length > 511 + 512) {
172 offset = length - 511 - 512;
173 }
174 length = length < 515 ? length : 515;
175 ret = bdrv_pread(file, offset, buffer, length);
176 if (ret < 0) {
177 error_setg_errno(errp, -ret, "Failed while reading UDIF trailer");
178 return ret;
179 }
180 for (i = 0; i < length - 3; i++) {
181 if (buffer[i] == 'k' && buffer[i+1] == 'o' &&
182 buffer[i+2] == 'l' && buffer[i+3] == 'y') {
183 return offset + i;
184 }
185 }
186 error_setg(errp, "Could not locate UDIF trailer in dmg file");
187 return -EINVAL;
188}
189
190
191typedef struct DmgHeaderState {
192
193
194 uint64_t data_fork_offset;
195
196 uint32_t max_compressed_size;
197 uint32_t max_sectors_per_chunk;
198} DmgHeaderState;
199
200static bool dmg_is_known_block_type(uint32_t entry_type)
201{
202 switch (entry_type) {
203 case UDZE:
204 case UDRW:
205 case UDIG:
206 case UDZO:
207 return true;
208 case UDBZ:
209 return !!dmg_uncompress_bz2;
210 case ULFO:
211 return !!dmg_uncompress_lzfse;
212 default:
213 return false;
214 }
215}
216
217static int dmg_read_mish_block(BDRVDMGState *s, DmgHeaderState *ds,
218 uint8_t *buffer, uint32_t count)
219{
220 uint32_t type, i;
221 int ret;
222 size_t new_size;
223 uint32_t chunk_count;
224 int64_t offset = 0;
225 uint64_t data_offset;
226 uint64_t in_offset = ds->data_fork_offset;
227 uint64_t out_offset;
228
229 type = buff_read_uint32(buffer, offset);
230
231 if (type != 0x6d697368 || count < 244) {
232
233 return 0;
234 }
235
236
237 out_offset = buff_read_uint64(buffer, offset + 8);
238
239
240 data_offset = buff_read_uint64(buffer, offset + 0x18);
241 in_offset += data_offset;
242
243
244 offset += 204;
245
246 chunk_count = (count - 204) / 40;
247 new_size = sizeof(uint64_t) * (s->n_chunks + chunk_count);
248 s->types = g_realloc(s->types, new_size / 2);
249 s->offsets = g_realloc(s->offsets, new_size);
250 s->lengths = g_realloc(s->lengths, new_size);
251 s->sectors = g_realloc(s->sectors, new_size);
252 s->sectorcounts = g_realloc(s->sectorcounts, new_size);
253
254 for (i = s->n_chunks; i < s->n_chunks + chunk_count; i++) {
255 s->types[i] = buff_read_uint32(buffer, offset);
256 if (!dmg_is_known_block_type(s->types[i])) {
257 chunk_count--;
258 i--;
259 offset += 40;
260 continue;
261 }
262
263
264 s->sectors[i] = buff_read_uint64(buffer, offset + 8);
265 s->sectors[i] += out_offset;
266
267
268 s->sectorcounts[i] = buff_read_uint64(buffer, offset + 0x10);
269
270
271
272 if (s->types[i] != UDZE && s->types[i] != UDIG
273 && s->sectorcounts[i] > DMG_SECTORCOUNTS_MAX) {
274 error_report("sector count %" PRIu64 " for chunk %" PRIu32
275 " is larger than max (%u)",
276 s->sectorcounts[i], i, DMG_SECTORCOUNTS_MAX);
277 ret = -EINVAL;
278 goto fail;
279 }
280
281
282 s->offsets[i] = buff_read_uint64(buffer, offset + 0x18);
283 s->offsets[i] += in_offset;
284
285
286 s->lengths[i] = buff_read_uint64(buffer, offset + 0x20);
287
288 if (s->lengths[i] > DMG_LENGTHS_MAX) {
289 error_report("length %" PRIu64 " for chunk %" PRIu32
290 " is larger than max (%u)",
291 s->lengths[i], i, DMG_LENGTHS_MAX);
292 ret = -EINVAL;
293 goto fail;
294 }
295
296 update_max_chunk_size(s, i, &ds->max_compressed_size,
297 &ds->max_sectors_per_chunk);
298 offset += 40;
299 }
300 s->n_chunks += chunk_count;
301 return 0;
302
303fail:
304 return ret;
305}
306
307static int dmg_read_resource_fork(BlockDriverState *bs, DmgHeaderState *ds,
308 uint64_t info_begin, uint64_t info_length)
309{
310 BDRVDMGState *s = bs->opaque;
311 int ret;
312 uint32_t count, rsrc_data_offset;
313 uint8_t *buffer = NULL;
314 uint64_t info_end;
315 uint64_t offset;
316
317
318 ret = read_uint32(bs, info_begin, &rsrc_data_offset);
319 if (ret < 0) {
320 goto fail;
321 } else if (rsrc_data_offset > info_length) {
322 ret = -EINVAL;
323 goto fail;
324 }
325
326
327 ret = read_uint32(bs, info_begin + 8, &count);
328 if (ret < 0) {
329 goto fail;
330 } else if (count == 0 || rsrc_data_offset + count > info_length) {
331 ret = -EINVAL;
332 goto fail;
333 }
334
335
336 offset = info_begin + rsrc_data_offset;
337
338
339
340 info_end = offset + count;
341
342
343 while (offset < info_end) {
344
345 ret = read_uint32(bs, offset, &count);
346 if (ret < 0) {
347 goto fail;
348 } else if (count == 0 || count > info_end - offset) {
349 ret = -EINVAL;
350 goto fail;
351 }
352 offset += 4;
353
354 buffer = g_realloc(buffer, count);
355 ret = bdrv_pread(bs->file, offset, buffer, count);
356 if (ret < 0) {
357 goto fail;
358 }
359
360 ret = dmg_read_mish_block(s, ds, buffer, count);
361 if (ret < 0) {
362 goto fail;
363 }
364
365 offset += count;
366 }
367 ret = 0;
368
369fail:
370 g_free(buffer);
371 return ret;
372}
373
374static int dmg_read_plist_xml(BlockDriverState *bs, DmgHeaderState *ds,
375 uint64_t info_begin, uint64_t info_length)
376{
377 BDRVDMGState *s = bs->opaque;
378 int ret;
379 uint8_t *buffer = NULL;
380 char *data_begin, *data_end;
381
382
383
384
385 if (info_length == 0 || info_length > 16 * 1024 * 1024) {
386 ret = -EINVAL;
387 goto fail;
388 }
389
390 buffer = g_malloc(info_length + 1);
391 buffer[info_length] = '\0';
392 ret = bdrv_pread(bs->file, info_begin, buffer, info_length);
393 if (ret != info_length) {
394 ret = -EINVAL;
395 goto fail;
396 }
397
398
399
400
401 data_end = (char *)buffer;
402 while ((data_begin = strstr(data_end, "<data>")) != NULL) {
403 guchar *mish;
404 gsize out_len = 0;
405
406 data_begin += 6;
407 data_end = strstr(data_begin, "</data>");
408
409 if (data_end == NULL) {
410 ret = -EINVAL;
411 goto fail;
412 }
413 *data_end++ = '\0';
414 mish = g_base64_decode(data_begin, &out_len);
415 ret = dmg_read_mish_block(s, ds, mish, (uint32_t)out_len);
416 g_free(mish);
417 if (ret < 0) {
418 goto fail;
419 }
420 }
421 ret = 0;
422
423fail:
424 g_free(buffer);
425 return ret;
426}
427
428static int dmg_open(BlockDriverState *bs, QDict *options, int flags,
429 Error **errp)
430{
431 BDRVDMGState *s = bs->opaque;
432 DmgHeaderState ds;
433 uint64_t rsrc_fork_offset, rsrc_fork_length;
434 uint64_t plist_xml_offset, plist_xml_length;
435 int64_t offset;
436 int ret;
437
438 ret = bdrv_apply_auto_read_only(bs, NULL, errp);
439 if (ret < 0) {
440 return ret;
441 }
442
443 bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
444 false, errp);
445 if (!bs->file) {
446 return -EINVAL;
447 }
448
449 block_module_load_one("dmg-bz2");
450 block_module_load_one("dmg-lzfse");
451
452 s->n_chunks = 0;
453 s->offsets = s->lengths = s->sectors = s->sectorcounts = NULL;
454
455 ds.data_fork_offset = 0;
456 ds.max_compressed_size = 1;
457 ds.max_sectors_per_chunk = 1;
458
459
460 offset = dmg_find_koly_offset(bs->file, errp);
461 if (offset < 0) {
462 ret = offset;
463 goto fail;
464 }
465
466
467 ret = read_uint64(bs, offset + 0x18, &ds.data_fork_offset);
468 if (ret < 0) {
469 goto fail;
470 } else if (ds.data_fork_offset > offset) {
471 ret = -EINVAL;
472 goto fail;
473 }
474
475
476 ret = read_uint64(bs, offset + 0x28, &rsrc_fork_offset);
477 if (ret < 0) {
478 goto fail;
479 }
480 ret = read_uint64(bs, offset + 0x30, &rsrc_fork_length);
481 if (ret < 0) {
482 goto fail;
483 }
484 if (rsrc_fork_offset >= offset ||
485 rsrc_fork_length > offset - rsrc_fork_offset) {
486 ret = -EINVAL;
487 goto fail;
488 }
489
490 ret = read_uint64(bs, offset + 0xd8, &plist_xml_offset);
491 if (ret < 0) {
492 goto fail;
493 }
494 ret = read_uint64(bs, offset + 0xe0, &plist_xml_length);
495 if (ret < 0) {
496 goto fail;
497 }
498 if (plist_xml_offset >= offset ||
499 plist_xml_length > offset - plist_xml_offset) {
500 ret = -EINVAL;
501 goto fail;
502 }
503 ret = read_uint64(bs, offset + 0x1ec, (uint64_t *)&bs->total_sectors);
504 if (ret < 0) {
505 goto fail;
506 }
507 if (bs->total_sectors < 0) {
508 ret = -EINVAL;
509 goto fail;
510 }
511 if (rsrc_fork_length != 0) {
512 ret = dmg_read_resource_fork(bs, &ds,
513 rsrc_fork_offset, rsrc_fork_length);
514 if (ret < 0) {
515 goto fail;
516 }
517 } else if (plist_xml_length != 0) {
518 ret = dmg_read_plist_xml(bs, &ds, plist_xml_offset, plist_xml_length);
519 if (ret < 0) {
520 goto fail;
521 }
522 } else {
523 ret = -EINVAL;
524 goto fail;
525 }
526
527
528 s->compressed_chunk = qemu_try_blockalign(bs->file->bs,
529 ds.max_compressed_size + 1);
530 s->uncompressed_chunk = qemu_try_blockalign(bs->file->bs,
531 512 * ds.max_sectors_per_chunk);
532 if (s->compressed_chunk == NULL || s->uncompressed_chunk == NULL) {
533 ret = -ENOMEM;
534 goto fail;
535 }
536
537 if (inflateInit(&s->zstream) != Z_OK) {
538 ret = -EINVAL;
539 goto fail;
540 }
541
542 s->current_chunk = s->n_chunks;
543
544 qemu_co_mutex_init(&s->lock);
545 return 0;
546
547fail:
548 g_free(s->types);
549 g_free(s->offsets);
550 g_free(s->lengths);
551 g_free(s->sectors);
552 g_free(s->sectorcounts);
553 qemu_vfree(s->compressed_chunk);
554 qemu_vfree(s->uncompressed_chunk);
555 return ret;
556}
557
558static void dmg_refresh_limits(BlockDriverState *bs, Error **errp)
559{
560 bs->bl.request_alignment = BDRV_SECTOR_SIZE;
561}
562
563static inline int is_sector_in_chunk(BDRVDMGState* s,
564 uint32_t chunk_num, uint64_t sector_num)
565{
566 if (chunk_num >= s->n_chunks || s->sectors[chunk_num] > sector_num ||
567 s->sectors[chunk_num] + s->sectorcounts[chunk_num] <= sector_num) {
568 return 0;
569 } else {
570 return -1;
571 }
572}
573
574static inline uint32_t search_chunk(BDRVDMGState *s, uint64_t sector_num)
575{
576
577 uint32_t chunk1 = 0, chunk2 = s->n_chunks, chunk3;
578 while (chunk1 <= chunk2) {
579 chunk3 = (chunk1 + chunk2) / 2;
580 if (s->sectors[chunk3] > sector_num) {
581 if (chunk3 == 0) {
582 goto err;
583 }
584 chunk2 = chunk3 - 1;
585 } else if (s->sectors[chunk3] + s->sectorcounts[chunk3] > sector_num) {
586 return chunk3;
587 } else {
588 chunk1 = chunk3 + 1;
589 }
590 }
591err:
592 return s->n_chunks;
593}
594
595static inline int dmg_read_chunk(BlockDriverState *bs, uint64_t sector_num)
596{
597 BDRVDMGState *s = bs->opaque;
598
599 if (!is_sector_in_chunk(s, s->current_chunk, sector_num)) {
600 int ret;
601 uint32_t chunk = search_chunk(s, sector_num);
602
603 if (chunk >= s->n_chunks) {
604 return -1;
605 }
606
607 s->current_chunk = s->n_chunks;
608 switch (s->types[chunk]) {
609 case UDZO: {
610
611
612 ret = bdrv_pread(bs->file, s->offsets[chunk],
613 s->compressed_chunk, s->lengths[chunk]);
614 if (ret != s->lengths[chunk]) {
615 return -1;
616 }
617
618 s->zstream.next_in = s->compressed_chunk;
619 s->zstream.avail_in = s->lengths[chunk];
620 s->zstream.next_out = s->uncompressed_chunk;
621 s->zstream.avail_out = 512 * s->sectorcounts[chunk];
622 ret = inflateReset(&s->zstream);
623 if (ret != Z_OK) {
624 return -1;
625 }
626 ret = inflate(&s->zstream, Z_FINISH);
627 if (ret != Z_STREAM_END ||
628 s->zstream.total_out != 512 * s->sectorcounts[chunk]) {
629 return -1;
630 }
631 break; }
632 case UDBZ:
633 if (!dmg_uncompress_bz2) {
634 break;
635 }
636
637
638 ret = bdrv_pread(bs->file, s->offsets[chunk],
639 s->compressed_chunk, s->lengths[chunk]);
640 if (ret != s->lengths[chunk]) {
641 return -1;
642 }
643
644 ret = dmg_uncompress_bz2((char *)s->compressed_chunk,
645 (unsigned int) s->lengths[chunk],
646 (char *)s->uncompressed_chunk,
647 (unsigned int)
648 (512 * s->sectorcounts[chunk]));
649 if (ret < 0) {
650 return ret;
651 }
652 break;
653 case ULFO:
654 if (!dmg_uncompress_lzfse) {
655 break;
656 }
657
658
659 ret = bdrv_pread(bs->file, s->offsets[chunk],
660 s->compressed_chunk, s->lengths[chunk]);
661 if (ret != s->lengths[chunk]) {
662 return -1;
663 }
664
665 ret = dmg_uncompress_lzfse((char *)s->compressed_chunk,
666 (unsigned int) s->lengths[chunk],
667 (char *)s->uncompressed_chunk,
668 (unsigned int)
669 (512 * s->sectorcounts[chunk]));
670 if (ret < 0) {
671 return ret;
672 }
673 break;
674 case UDRW:
675 ret = bdrv_pread(bs->file, s->offsets[chunk],
676 s->uncompressed_chunk, s->lengths[chunk]);
677 if (ret != s->lengths[chunk]) {
678 return -1;
679 }
680 break;
681 case UDZE:
682 case UDIG:
683
684
685 break;
686 }
687 s->current_chunk = chunk;
688 }
689 return 0;
690}
691
692static int coroutine_fn
693dmg_co_preadv(BlockDriverState *bs, uint64_t offset, uint64_t bytes,
694 QEMUIOVector *qiov, int flags)
695{
696 BDRVDMGState *s = bs->opaque;
697 uint64_t sector_num = offset >> BDRV_SECTOR_BITS;
698 int nb_sectors = bytes >> BDRV_SECTOR_BITS;
699 int ret, i;
700
701 assert((offset & (BDRV_SECTOR_SIZE - 1)) == 0);
702 assert((bytes & (BDRV_SECTOR_SIZE - 1)) == 0);
703
704 qemu_co_mutex_lock(&s->lock);
705
706 for (i = 0; i < nb_sectors; i++) {
707 uint32_t sector_offset_in_chunk;
708 void *data;
709
710 if (dmg_read_chunk(bs, sector_num + i) != 0) {
711 ret = -EIO;
712 goto fail;
713 }
714
715
716
717 if (s->types[s->current_chunk] == UDZE
718 || s->types[s->current_chunk] == UDIG) {
719 qemu_iovec_memset(qiov, i * 512, 0, 512);
720 continue;
721 }
722 sector_offset_in_chunk = sector_num + i - s->sectors[s->current_chunk];
723 data = s->uncompressed_chunk + sector_offset_in_chunk * 512;
724 qemu_iovec_from_buf(qiov, i * 512, data, 512);
725 }
726
727 ret = 0;
728fail:
729 qemu_co_mutex_unlock(&s->lock);
730 return ret;
731}
732
733static void dmg_close(BlockDriverState *bs)
734{
735 BDRVDMGState *s = bs->opaque;
736
737 g_free(s->types);
738 g_free(s->offsets);
739 g_free(s->lengths);
740 g_free(s->sectors);
741 g_free(s->sectorcounts);
742 qemu_vfree(s->compressed_chunk);
743 qemu_vfree(s->uncompressed_chunk);
744
745 inflateEnd(&s->zstream);
746}
747
748static BlockDriver bdrv_dmg = {
749 .format_name = "dmg",
750 .instance_size = sizeof(BDRVDMGState),
751 .bdrv_probe = dmg_probe,
752 .bdrv_open = dmg_open,
753 .bdrv_refresh_limits = dmg_refresh_limits,
754 .bdrv_child_perm = bdrv_format_default_perms,
755 .bdrv_co_preadv = dmg_co_preadv,
756 .bdrv_close = dmg_close,
757};
758
759static void bdrv_dmg_init(void)
760{
761 bdrv_register(&bdrv_dmg);
762}
763
764block_init(bdrv_dmg_init);
765