ui: add tracing of VNC operations related to QIOChannel
[qemu/ar7.git] / block / dmg.c
blob6c0711f5636a40758107043a0b4cb9f728c70dd9
1 /*
2 * QEMU Block driver for DMG images
4 * Copyright (c) 2004 Johannes E. Schindelin
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22 * THE SOFTWARE.
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"
33 int (*dmg_uncompress_bz2)(char *next_in, unsigned int avail_in,
34 char *next_out, unsigned int avail_out);
36 enum {
37 /* Limit chunk sizes to prevent unreasonable amounts of memory being used
38 * or truncating when converting to 32-bit types
40 DMG_LENGTHS_MAX = 64 * 1024 * 1024, /* 64 MB */
41 DMG_SECTORCOUNTS_MAX = DMG_LENGTHS_MAX / 512,
44 static int dmg_probe(const uint8_t *buf, int buf_size, const char *filename)
46 int len;
48 if (!filename) {
49 return 0;
52 len = strlen(filename);
53 if (len > 4 && !strcmp(filename + len - 4, ".dmg")) {
54 return 2;
56 return 0;
59 static int read_uint64(BlockDriverState *bs, int64_t offset, uint64_t *result)
61 uint64_t buffer;
62 int ret;
64 ret = bdrv_pread(bs->file, offset, &buffer, 8);
65 if (ret < 0) {
66 return ret;
69 *result = be64_to_cpu(buffer);
70 return 0;
73 static int read_uint32(BlockDriverState *bs, int64_t offset, uint32_t *result)
75 uint32_t buffer;
76 int ret;
78 ret = bdrv_pread(bs->file, offset, &buffer, 4);
79 if (ret < 0) {
80 return ret;
83 *result = be32_to_cpu(buffer);
84 return 0;
87 static inline uint64_t buff_read_uint64(const uint8_t *buffer, int64_t offset)
89 return be64_to_cpu(*(uint64_t *)&buffer[offset]);
92 static inline uint32_t buff_read_uint32(const uint8_t *buffer, int64_t offset)
94 return be32_to_cpu(*(uint32_t *)&buffer[offset]);
97 /* Increase max chunk sizes, if necessary. This function is used to calculate
98 * the buffer sizes needed for compressed/uncompressed chunk I/O.
100 static void update_max_chunk_size(BDRVDMGState *s, uint32_t chunk,
101 uint32_t *max_compressed_size,
102 uint32_t *max_sectors_per_chunk)
104 uint32_t compressed_size = 0;
105 uint32_t uncompressed_sectors = 0;
107 switch (s->types[chunk]) {
108 case 0x80000005: /* zlib compressed */
109 case 0x80000006: /* bzip2 compressed */
110 compressed_size = s->lengths[chunk];
111 uncompressed_sectors = s->sectorcounts[chunk];
112 break;
113 case 1: /* copy */
114 uncompressed_sectors = DIV_ROUND_UP(s->lengths[chunk], 512);
115 break;
116 case 2: /* zero */
117 /* as the all-zeroes block may be large, it is treated specially: the
118 * sector is not copied from a large buffer, a simple memset is used
119 * instead. Therefore uncompressed_sectors does not need to be set. */
120 break;
123 if (compressed_size > *max_compressed_size) {
124 *max_compressed_size = compressed_size;
126 if (uncompressed_sectors > *max_sectors_per_chunk) {
127 *max_sectors_per_chunk = uncompressed_sectors;
131 static int64_t dmg_find_koly_offset(BdrvChild *file, Error **errp)
133 BlockDriverState *file_bs = file->bs;
134 int64_t length;
135 int64_t offset = 0;
136 uint8_t buffer[515];
137 int i, ret;
139 /* bdrv_getlength returns a multiple of block size (512), rounded up. Since
140 * dmg images can have odd sizes, try to look for the "koly" magic which
141 * marks the begin of the UDIF trailer (512 bytes). This magic can be found
142 * in the last 511 bytes of the second-last sector or the first 4 bytes of
143 * the last sector (search space: 515 bytes) */
144 length = bdrv_getlength(file_bs);
145 if (length < 0) {
146 error_setg_errno(errp, -length,
147 "Failed to get file size while reading UDIF trailer");
148 return length;
149 } else if (length < 512) {
150 error_setg(errp, "dmg file must be at least 512 bytes long");
151 return -EINVAL;
153 if (length > 511 + 512) {
154 offset = length - 511 - 512;
156 length = length < 515 ? length : 515;
157 ret = bdrv_pread(file, offset, buffer, length);
158 if (ret < 0) {
159 error_setg_errno(errp, -ret, "Failed while reading UDIF trailer");
160 return ret;
162 for (i = 0; i < length - 3; i++) {
163 if (buffer[i] == 'k' && buffer[i+1] == 'o' &&
164 buffer[i+2] == 'l' && buffer[i+3] == 'y') {
165 return offset + i;
168 error_setg(errp, "Could not locate UDIF trailer in dmg file");
169 return -EINVAL;
172 /* used when building the sector table */
173 typedef struct DmgHeaderState {
174 /* used internally by dmg_read_mish_block to remember offsets of blocks
175 * across calls */
176 uint64_t data_fork_offset;
177 /* exported for dmg_open */
178 uint32_t max_compressed_size;
179 uint32_t max_sectors_per_chunk;
180 } DmgHeaderState;
182 static bool dmg_is_known_block_type(uint32_t entry_type)
184 switch (entry_type) {
185 case 0x00000001: /* uncompressed */
186 case 0x00000002: /* zeroes */
187 case 0x80000005: /* zlib */
188 return true;
189 case 0x80000006: /* bzip2 */
190 return !!dmg_uncompress_bz2;
191 default:
192 return false;
196 static int dmg_read_mish_block(BDRVDMGState *s, DmgHeaderState *ds,
197 uint8_t *buffer, uint32_t count)
199 uint32_t type, i;
200 int ret;
201 size_t new_size;
202 uint32_t chunk_count;
203 int64_t offset = 0;
204 uint64_t data_offset;
205 uint64_t in_offset = ds->data_fork_offset;
206 uint64_t out_offset;
208 type = buff_read_uint32(buffer, offset);
209 /* skip data that is not a valid MISH block (invalid magic or too small) */
210 if (type != 0x6d697368 || count < 244) {
211 /* assume success for now */
212 return 0;
215 /* chunk offsets are relative to this sector number */
216 out_offset = buff_read_uint64(buffer, offset + 8);
218 /* location in data fork for (compressed) blob (in bytes) */
219 data_offset = buff_read_uint64(buffer, offset + 0x18);
220 in_offset += data_offset;
222 /* move to begin of chunk entries */
223 offset += 204;
225 chunk_count = (count - 204) / 40;
226 new_size = sizeof(uint64_t) * (s->n_chunks + chunk_count);
227 s->types = g_realloc(s->types, new_size / 2);
228 s->offsets = g_realloc(s->offsets, new_size);
229 s->lengths = g_realloc(s->lengths, new_size);
230 s->sectors = g_realloc(s->sectors, new_size);
231 s->sectorcounts = g_realloc(s->sectorcounts, new_size);
233 for (i = s->n_chunks; i < s->n_chunks + chunk_count; i++) {
234 s->types[i] = buff_read_uint32(buffer, offset);
235 if (!dmg_is_known_block_type(s->types[i])) {
236 chunk_count--;
237 i--;
238 offset += 40;
239 continue;
242 /* sector number */
243 s->sectors[i] = buff_read_uint64(buffer, offset + 8);
244 s->sectors[i] += out_offset;
246 /* sector count */
247 s->sectorcounts[i] = buff_read_uint64(buffer, offset + 0x10);
249 /* all-zeroes sector (type 2) does not need to be "uncompressed" and can
250 * therefore be unbounded. */
251 if (s->types[i] != 2 && s->sectorcounts[i] > DMG_SECTORCOUNTS_MAX) {
252 error_report("sector count %" PRIu64 " for chunk %" PRIu32
253 " is larger than max (%u)",
254 s->sectorcounts[i], i, DMG_SECTORCOUNTS_MAX);
255 ret = -EINVAL;
256 goto fail;
259 /* offset in (compressed) data fork */
260 s->offsets[i] = buff_read_uint64(buffer, offset + 0x18);
261 s->offsets[i] += in_offset;
263 /* length in (compressed) data fork */
264 s->lengths[i] = buff_read_uint64(buffer, offset + 0x20);
266 if (s->lengths[i] > DMG_LENGTHS_MAX) {
267 error_report("length %" PRIu64 " for chunk %" PRIu32
268 " is larger than max (%u)",
269 s->lengths[i], i, DMG_LENGTHS_MAX);
270 ret = -EINVAL;
271 goto fail;
274 update_max_chunk_size(s, i, &ds->max_compressed_size,
275 &ds->max_sectors_per_chunk);
276 offset += 40;
278 s->n_chunks += chunk_count;
279 return 0;
281 fail:
282 return ret;
285 static int dmg_read_resource_fork(BlockDriverState *bs, DmgHeaderState *ds,
286 uint64_t info_begin, uint64_t info_length)
288 BDRVDMGState *s = bs->opaque;
289 int ret;
290 uint32_t count, rsrc_data_offset;
291 uint8_t *buffer = NULL;
292 uint64_t info_end;
293 uint64_t offset;
295 /* read offset from begin of resource fork (info_begin) to resource data */
296 ret = read_uint32(bs, info_begin, &rsrc_data_offset);
297 if (ret < 0) {
298 goto fail;
299 } else if (rsrc_data_offset > info_length) {
300 ret = -EINVAL;
301 goto fail;
304 /* read length of resource data */
305 ret = read_uint32(bs, info_begin + 8, &count);
306 if (ret < 0) {
307 goto fail;
308 } else if (count == 0 || rsrc_data_offset + count > info_length) {
309 ret = -EINVAL;
310 goto fail;
313 /* begin of resource data (consisting of one or more resources) */
314 offset = info_begin + rsrc_data_offset;
316 /* end of resource data (there is possibly a following resource map
317 * which will be ignored). */
318 info_end = offset + count;
320 /* read offsets (mish blocks) from one or more resources in resource data */
321 while (offset < info_end) {
322 /* size of following resource */
323 ret = read_uint32(bs, offset, &count);
324 if (ret < 0) {
325 goto fail;
326 } else if (count == 0 || count > info_end - offset) {
327 ret = -EINVAL;
328 goto fail;
330 offset += 4;
332 buffer = g_realloc(buffer, count);
333 ret = bdrv_pread(bs->file, offset, buffer, count);
334 if (ret < 0) {
335 goto fail;
338 ret = dmg_read_mish_block(s, ds, buffer, count);
339 if (ret < 0) {
340 goto fail;
342 /* advance offset by size of resource */
343 offset += count;
345 ret = 0;
347 fail:
348 g_free(buffer);
349 return ret;
352 static int dmg_read_plist_xml(BlockDriverState *bs, DmgHeaderState *ds,
353 uint64_t info_begin, uint64_t info_length)
355 BDRVDMGState *s = bs->opaque;
356 int ret;
357 uint8_t *buffer = NULL;
358 char *data_begin, *data_end;
360 /* Have at least some length to avoid NULL for g_malloc. Attempt to set a
361 * safe upper cap on the data length. A test sample had a XML length of
362 * about 1 MiB. */
363 if (info_length == 0 || info_length > 16 * 1024 * 1024) {
364 ret = -EINVAL;
365 goto fail;
368 buffer = g_malloc(info_length + 1);
369 buffer[info_length] = '\0';
370 ret = bdrv_pread(bs->file, info_begin, buffer, info_length);
371 if (ret != info_length) {
372 ret = -EINVAL;
373 goto fail;
376 /* look for <data>...</data>. The data is 284 (0x11c) bytes after base64
377 * decode. The actual data element has 431 (0x1af) bytes which includes tabs
378 * and line feeds. */
379 data_end = (char *)buffer;
380 while ((data_begin = strstr(data_end, "<data>")) != NULL) {
381 guchar *mish;
382 gsize out_len = 0;
384 data_begin += 6;
385 data_end = strstr(data_begin, "</data>");
386 /* malformed XML? */
387 if (data_end == NULL) {
388 ret = -EINVAL;
389 goto fail;
391 *data_end++ = '\0';
392 mish = g_base64_decode(data_begin, &out_len);
393 ret = dmg_read_mish_block(s, ds, mish, (uint32_t)out_len);
394 g_free(mish);
395 if (ret < 0) {
396 goto fail;
399 ret = 0;
401 fail:
402 g_free(buffer);
403 return ret;
406 static int dmg_open(BlockDriverState *bs, QDict *options, int flags,
407 Error **errp)
409 BDRVDMGState *s = bs->opaque;
410 DmgHeaderState ds;
411 uint64_t rsrc_fork_offset, rsrc_fork_length;
412 uint64_t plist_xml_offset, plist_xml_length;
413 int64_t offset;
414 int ret;
416 bs->file = bdrv_open_child(NULL, options, "file", bs, &child_file,
417 false, errp);
418 if (!bs->file) {
419 return -EINVAL;
422 ret = bdrv_set_read_only(bs, true, errp);
423 if (ret < 0) {
424 return ret;
427 block_module_load_one("dmg-bz2");
429 s->n_chunks = 0;
430 s->offsets = s->lengths = s->sectors = s->sectorcounts = NULL;
431 /* used by dmg_read_mish_block to keep track of the current I/O position */
432 ds.data_fork_offset = 0;
433 ds.max_compressed_size = 1;
434 ds.max_sectors_per_chunk = 1;
436 /* locate the UDIF trailer */
437 offset = dmg_find_koly_offset(bs->file, errp);
438 if (offset < 0) {
439 ret = offset;
440 goto fail;
443 /* offset of data fork (DataForkOffset) */
444 ret = read_uint64(bs, offset + 0x18, &ds.data_fork_offset);
445 if (ret < 0) {
446 goto fail;
447 } else if (ds.data_fork_offset > offset) {
448 ret = -EINVAL;
449 goto fail;
452 /* offset of resource fork (RsrcForkOffset) */
453 ret = read_uint64(bs, offset + 0x28, &rsrc_fork_offset);
454 if (ret < 0) {
455 goto fail;
457 ret = read_uint64(bs, offset + 0x30, &rsrc_fork_length);
458 if (ret < 0) {
459 goto fail;
461 if (rsrc_fork_offset >= offset ||
462 rsrc_fork_length > offset - rsrc_fork_offset) {
463 ret = -EINVAL;
464 goto fail;
466 /* offset of property list (XMLOffset) */
467 ret = read_uint64(bs, offset + 0xd8, &plist_xml_offset);
468 if (ret < 0) {
469 goto fail;
471 ret = read_uint64(bs, offset + 0xe0, &plist_xml_length);
472 if (ret < 0) {
473 goto fail;
475 if (plist_xml_offset >= offset ||
476 plist_xml_length > offset - plist_xml_offset) {
477 ret = -EINVAL;
478 goto fail;
480 ret = read_uint64(bs, offset + 0x1ec, (uint64_t *)&bs->total_sectors);
481 if (ret < 0) {
482 goto fail;
484 if (bs->total_sectors < 0) {
485 ret = -EINVAL;
486 goto fail;
488 if (rsrc_fork_length != 0) {
489 ret = dmg_read_resource_fork(bs, &ds,
490 rsrc_fork_offset, rsrc_fork_length);
491 if (ret < 0) {
492 goto fail;
494 } else if (plist_xml_length != 0) {
495 ret = dmg_read_plist_xml(bs, &ds, plist_xml_offset, plist_xml_length);
496 if (ret < 0) {
497 goto fail;
499 } else {
500 ret = -EINVAL;
501 goto fail;
504 /* initialize zlib engine */
505 s->compressed_chunk = qemu_try_blockalign(bs->file->bs,
506 ds.max_compressed_size + 1);
507 s->uncompressed_chunk = qemu_try_blockalign(bs->file->bs,
508 512 * ds.max_sectors_per_chunk);
509 if (s->compressed_chunk == NULL || s->uncompressed_chunk == NULL) {
510 ret = -ENOMEM;
511 goto fail;
514 if (inflateInit(&s->zstream) != Z_OK) {
515 ret = -EINVAL;
516 goto fail;
519 s->current_chunk = s->n_chunks;
521 qemu_co_mutex_init(&s->lock);
522 return 0;
524 fail:
525 g_free(s->types);
526 g_free(s->offsets);
527 g_free(s->lengths);
528 g_free(s->sectors);
529 g_free(s->sectorcounts);
530 qemu_vfree(s->compressed_chunk);
531 qemu_vfree(s->uncompressed_chunk);
532 return ret;
535 static void dmg_refresh_limits(BlockDriverState *bs, Error **errp)
537 bs->bl.request_alignment = BDRV_SECTOR_SIZE; /* No sub-sector I/O */
540 static inline int is_sector_in_chunk(BDRVDMGState* s,
541 uint32_t chunk_num, uint64_t sector_num)
543 if (chunk_num >= s->n_chunks || s->sectors[chunk_num] > sector_num ||
544 s->sectors[chunk_num] + s->sectorcounts[chunk_num] <= sector_num) {
545 return 0;
546 } else {
547 return -1;
551 static inline uint32_t search_chunk(BDRVDMGState *s, uint64_t sector_num)
553 /* binary search */
554 uint32_t chunk1 = 0, chunk2 = s->n_chunks, chunk3;
555 while (chunk1 != chunk2) {
556 chunk3 = (chunk1 + chunk2) / 2;
557 if (s->sectors[chunk3] > sector_num) {
558 chunk2 = chunk3;
559 } else if (s->sectors[chunk3] + s->sectorcounts[chunk3] > sector_num) {
560 return chunk3;
561 } else {
562 chunk1 = chunk3;
565 return s->n_chunks; /* error */
568 static inline int dmg_read_chunk(BlockDriverState *bs, uint64_t sector_num)
570 BDRVDMGState *s = bs->opaque;
572 if (!is_sector_in_chunk(s, s->current_chunk, sector_num)) {
573 int ret;
574 uint32_t chunk = search_chunk(s, sector_num);
576 if (chunk >= s->n_chunks) {
577 return -1;
580 s->current_chunk = s->n_chunks;
581 switch (s->types[chunk]) { /* block entry type */
582 case 0x80000005: { /* zlib compressed */
583 /* we need to buffer, because only the chunk as whole can be
584 * inflated. */
585 ret = bdrv_pread(bs->file, s->offsets[chunk],
586 s->compressed_chunk, s->lengths[chunk]);
587 if (ret != s->lengths[chunk]) {
588 return -1;
591 s->zstream.next_in = s->compressed_chunk;
592 s->zstream.avail_in = s->lengths[chunk];
593 s->zstream.next_out = s->uncompressed_chunk;
594 s->zstream.avail_out = 512 * s->sectorcounts[chunk];
595 ret = inflateReset(&s->zstream);
596 if (ret != Z_OK) {
597 return -1;
599 ret = inflate(&s->zstream, Z_FINISH);
600 if (ret != Z_STREAM_END ||
601 s->zstream.total_out != 512 * s->sectorcounts[chunk]) {
602 return -1;
604 break; }
605 case 0x80000006: /* bzip2 compressed */
606 if (!dmg_uncompress_bz2) {
607 break;
609 /* we need to buffer, because only the chunk as whole can be
610 * inflated. */
611 ret = bdrv_pread(bs->file, s->offsets[chunk],
612 s->compressed_chunk, s->lengths[chunk]);
613 if (ret != s->lengths[chunk]) {
614 return -1;
617 ret = dmg_uncompress_bz2((char *)s->compressed_chunk,
618 (unsigned int) s->lengths[chunk],
619 (char *)s->uncompressed_chunk,
620 (unsigned int)
621 (512 * s->sectorcounts[chunk]));
622 if (ret < 0) {
623 return ret;
625 break;
626 case 1: /* copy */
627 ret = bdrv_pread(bs->file, s->offsets[chunk],
628 s->uncompressed_chunk, s->lengths[chunk]);
629 if (ret != s->lengths[chunk]) {
630 return -1;
632 break;
633 case 2: /* zero */
634 /* see dmg_read, it is treated specially. No buffer needs to be
635 * pre-filled, the zeroes can be set directly. */
636 break;
638 s->current_chunk = chunk;
640 return 0;
643 static int coroutine_fn
644 dmg_co_preadv(BlockDriverState *bs, uint64_t offset, uint64_t bytes,
645 QEMUIOVector *qiov, int flags)
647 BDRVDMGState *s = bs->opaque;
648 uint64_t sector_num = offset >> BDRV_SECTOR_BITS;
649 int nb_sectors = bytes >> BDRV_SECTOR_BITS;
650 int ret, i;
652 assert((offset & (BDRV_SECTOR_SIZE - 1)) == 0);
653 assert((bytes & (BDRV_SECTOR_SIZE - 1)) == 0);
655 qemu_co_mutex_lock(&s->lock);
657 for (i = 0; i < nb_sectors; i++) {
658 uint32_t sector_offset_in_chunk;
659 void *data;
661 if (dmg_read_chunk(bs, sector_num + i) != 0) {
662 ret = -EIO;
663 goto fail;
665 /* Special case: current chunk is all zeroes. Do not perform a memcpy as
666 * s->uncompressed_chunk may be too small to cover the large all-zeroes
667 * section. dmg_read_chunk is called to find s->current_chunk */
668 if (s->types[s->current_chunk] == 2) { /* all zeroes block entry */
669 qemu_iovec_memset(qiov, i * 512, 0, 512);
670 continue;
672 sector_offset_in_chunk = sector_num + i - s->sectors[s->current_chunk];
673 data = s->uncompressed_chunk + sector_offset_in_chunk * 512;
674 qemu_iovec_from_buf(qiov, i * 512, data, 512);
677 ret = 0;
678 fail:
679 qemu_co_mutex_unlock(&s->lock);
680 return ret;
683 static void dmg_close(BlockDriverState *bs)
685 BDRVDMGState *s = bs->opaque;
687 g_free(s->types);
688 g_free(s->offsets);
689 g_free(s->lengths);
690 g_free(s->sectors);
691 g_free(s->sectorcounts);
692 qemu_vfree(s->compressed_chunk);
693 qemu_vfree(s->uncompressed_chunk);
695 inflateEnd(&s->zstream);
698 static BlockDriver bdrv_dmg = {
699 .format_name = "dmg",
700 .instance_size = sizeof(BDRVDMGState),
701 .bdrv_probe = dmg_probe,
702 .bdrv_open = dmg_open,
703 .bdrv_refresh_limits = dmg_refresh_limits,
704 .bdrv_child_perm = bdrv_format_default_perms,
705 .bdrv_co_preadv = dmg_co_preadv,
706 .bdrv_close = dmg_close,
709 static void bdrv_dmg_init(void)
711 bdrv_register(&bdrv_dmg);
714 block_init(bdrv_dmg_init);