diff options
| -rw-r--r-- | block/dmg.c | 36 |
1 files changed, 23 insertions, 13 deletions
diff --git a/block/dmg.c b/block/dmg.c index d144a5e810..cc584b55aa 100644 --- a/block/dmg.c +++ b/block/dmg.c @@ -192,6 +192,18 @@ typedef struct DmgHeaderState { uint32_t max_sectors_per_chunk; } DmgHeaderState; +static bool dmg_is_known_block_type(uint32_t entry_type) +{ + switch (entry_type) { + case 0x00000001: /* uncompressed */ + case 0x00000002: /* zeroes */ + case 0x80000005: /* zlib */ + return true; + default: + return false; + } +} + static int dmg_read_mish_block(BDRVDMGState *s, DmgHeaderState *ds, uint8_t *buffer, uint32_t count) { @@ -231,22 +243,19 @@ static int dmg_read_mish_block(BDRVDMGState *s, DmgHeaderState *ds, for (i = s->n_chunks; i < s->n_chunks + chunk_count; i++) { s->types[i] = buff_read_uint32(buffer, offset); - offset += 4; - if (s->types[i] != 0x80000005 && s->types[i] != 1 && - s->types[i] != 2) { + if (!dmg_is_known_block_type(s->types[i])) { chunk_count--; i--; - offset += 36; + offset += 40; continue; } - offset += 4; - s->sectors[i] = buff_read_uint64(buffer, offset); + /* sector number */ + s->sectors[i] = buff_read_uint64(buffer, offset + 8); s->sectors[i] += out_offset; - offset += 8; - s->sectorcounts[i] = buff_read_uint64(buffer, offset); - offset += 8; + /* sector count */ + s->sectorcounts[i] = buff_read_uint64(buffer, offset + 0x10); if (s->sectorcounts[i] > DMG_SECTORCOUNTS_MAX) { error_report("sector count %" PRIu64 " for chunk %" PRIu32 @@ -256,12 +265,12 @@ static int dmg_read_mish_block(BDRVDMGState *s, DmgHeaderState *ds, goto fail; } - s->offsets[i] = buff_read_uint64(buffer, offset); + /* offset in (compressed) data fork */ + s->offsets[i] = buff_read_uint64(buffer, offset + 0x18); s->offsets[i] += in_offset; - offset += 8; - s->lengths[i] = buff_read_uint64(buffer, offset); - offset += 8; + /* length in (compressed) data fork */ + s->lengths[i] = buff_read_uint64(buffer, offset + 0x20); if (s->lengths[i] > DMG_LENGTHS_MAX) { error_report("length %" PRIu64 " for chunk %" PRIu32 @@ -273,6 +282,7 @@ static int dmg_read_mish_block(BDRVDMGState *s, DmgHeaderState *ds, update_max_chunk_size(s, i, &ds->max_compressed_size, &ds->max_sectors_per_chunk); + offset += 40; } s->n_chunks += chunk_count; return 0; |