diff options
Diffstat (limited to 'block/vhdx.c')
| -rw-r--r-- | block/vhdx.c | 89 |
1 files changed, 53 insertions, 36 deletions
diff --git a/block/vhdx.c b/block/vhdx.c index fedcf9f9ca..febce21f82 100644 --- a/block/vhdx.c +++ b/block/vhdx.c @@ -135,10 +135,8 @@ typedef struct VHDXSectorInfo { * buf: buffer pointer * size: size of buffer (must be > crc_offset+4) * - * Note: The resulting checksum is in the CPU endianness, not necessarily - * in the file format endianness (LE). Any header export to disk should - * make sure that vhdx_header_le_export() is used to convert to the - * correct endianness + * Note: The buffer should have all multi-byte data in little-endian format, + * and the resulting checksum is in little endian format. */ uint32_t vhdx_update_checksum(uint8_t *buf, size_t size, int crc_offset) { @@ -149,6 +147,7 @@ uint32_t vhdx_update_checksum(uint8_t *buf, size_t size, int crc_offset) memset(buf + crc_offset, 0, sizeof(crc)); crc = crc32c(0xffffffff, buf, size); + cpu_to_le32s(&crc); memcpy(buf + crc_offset, &crc, sizeof(crc)); return crc; @@ -300,7 +299,7 @@ static int vhdx_write_header(BlockDriverState *bs_file, VHDXHeader *hdr, { uint8_t *buffer = NULL; int ret; - VHDXHeader header_le; + VHDXHeader *header_le; assert(bs_file != NULL); assert(hdr != NULL); @@ -321,11 +320,12 @@ static int vhdx_write_header(BlockDriverState *bs_file, VHDXHeader *hdr, } /* overwrite the actual VHDXHeader portion */ - memcpy(buffer, hdr, sizeof(VHDXHeader)); - hdr->checksum = vhdx_update_checksum(buffer, VHDX_HEADER_SIZE, - offsetof(VHDXHeader, checksum)); - vhdx_header_le_export(hdr, &header_le); - ret = bdrv_pwrite_sync(bs_file, offset, &header_le, sizeof(VHDXHeader)); + header_le = (VHDXHeader *)buffer; + memcpy(header_le, hdr, sizeof(VHDXHeader)); + vhdx_header_le_export(hdr, header_le); + vhdx_update_checksum(buffer, VHDX_HEADER_SIZE, + offsetof(VHDXHeader, checksum)); + ret = bdrv_pwrite_sync(bs_file, offset, header_le, sizeof(VHDXHeader)); exit: qemu_vfree(buffer); @@ -432,13 +432,14 @@ static void vhdx_parse_header(BlockDriverState *bs, BDRVVHDXState *s, } /* copy over just the relevant portion that we need */ memcpy(header1, buffer, sizeof(VHDXHeader)); - vhdx_header_le_import(header1); - if (vhdx_checksum_is_valid(buffer, VHDX_HEADER_SIZE, 4) && - !memcmp(&header1->signature, "head", 4) && - header1->version == 1) { - h1_seq = header1->sequence_number; - h1_valid = true; + if (vhdx_checksum_is_valid(buffer, VHDX_HEADER_SIZE, 4)) { + vhdx_header_le_import(header1); + if (header1->signature == VHDX_HEADER_SIGNATURE && + header1->version == 1) { + h1_seq = header1->sequence_number; + h1_valid = true; + } } ret = bdrv_pread(bs->file, VHDX_HEADER2_OFFSET, buffer, VHDX_HEADER_SIZE); @@ -447,13 +448,14 @@ static void vhdx_parse_header(BlockDriverState *bs, BDRVVHDXState *s, } /* copy over just the relevant portion that we need */ memcpy(header2, buffer, sizeof(VHDXHeader)); - vhdx_header_le_import(header2); - if (vhdx_checksum_is_valid(buffer, VHDX_HEADER_SIZE, 4) && - !memcmp(&header2->signature, "head", 4) && - header2->version == 1) { - h2_seq = header2->sequence_number; - h2_valid = true; + if (vhdx_checksum_is_valid(buffer, VHDX_HEADER_SIZE, 4)) { + vhdx_header_le_import(header2); + if (header2->signature == VHDX_HEADER_SIGNATURE && + header2->version == 1) { + h2_seq = header2->sequence_number; + h2_valid = true; + } } /* If there is only 1 valid header (or no valid headers), we @@ -519,15 +521,21 @@ static int vhdx_open_region_tables(BlockDriverState *bs, BDRVVHDXState *s) goto fail; } memcpy(&s->rt, buffer, sizeof(s->rt)); - vhdx_region_header_le_import(&s->rt); offset += sizeof(s->rt); - if (!vhdx_checksum_is_valid(buffer, VHDX_HEADER_BLOCK_SIZE, 4) || - memcmp(&s->rt.signature, "regi", 4)) { + if (!vhdx_checksum_is_valid(buffer, VHDX_HEADER_BLOCK_SIZE, 4)) { + ret = -EINVAL; + goto fail; + } + + vhdx_region_header_le_import(&s->rt); + + if (s->rt.signature != VHDX_REGION_SIGNATURE) { ret = -EINVAL; goto fail; } + /* Per spec, maximum region table entry count is 2047 */ if (s->rt.entry_count > 2047) { ret = -EINVAL; @@ -630,7 +638,7 @@ static int vhdx_parse_metadata(BlockDriverState *bs, BDRVVHDXState *s) vhdx_metadata_header_le_import(&s->metadata_hdr); - if (memcmp(&s->metadata_hdr.signature, "metadata", 8)) { + if (s->metadata_hdr.signature != VHDX_METADATA_SIGNATURE) { ret = -EINVAL; goto exit; } @@ -951,7 +959,6 @@ static int vhdx_open(BlockDriverState *bs, QDict *options, int flags, /* s->bat is freed in vhdx_close() */ s->bat = qemu_blockalign(bs, s->bat_rt.length); - ret = bdrv_pread(bs->file, s->bat_offset, s->bat, s->bat_rt.length); if (ret < 0) { goto fail; @@ -1540,7 +1547,8 @@ exit: */ static int vhdx_create_bat(BlockDriverState *bs, BDRVVHDXState *s, uint64_t image_size, VHDXImageType type, - bool use_zero_blocks, VHDXRegionTableEntry *rt_bat) + bool use_zero_blocks, uint64_t file_offset, + uint32_t length) { int ret = 0; uint64_t data_file_offset; @@ -1555,7 +1563,7 @@ static int vhdx_create_bat(BlockDriverState *bs, BDRVVHDXState *s, /* this gives a data start after BAT/bitmap entries, and well * past any metadata entries (with a 4 MB buffer for future * expansion */ - data_file_offset = rt_bat->file_offset + rt_bat->length + 5 * MiB; + data_file_offset = file_offset + length + 5 * MiB; total_sectors = image_size >> s->logical_sector_size_bits; if (type == VHDX_TYPE_DYNAMIC) { @@ -1579,7 +1587,7 @@ static int vhdx_create_bat(BlockDriverState *bs, BDRVVHDXState *s, use_zero_blocks || bdrv_has_zero_init(bs) == 0) { /* for a fixed file, the default BAT entry is not zero */ - s->bat = g_malloc0(rt_bat->length); + s->bat = g_malloc0(length); block_state = type == VHDX_TYPE_FIXED ? PAYLOAD_BLOCK_FULLY_PRESENT : PAYLOAD_BLOCK_NOT_PRESENT; block_state = use_zero_blocks ? PAYLOAD_BLOCK_ZERO : block_state; @@ -1594,7 +1602,7 @@ static int vhdx_create_bat(BlockDriverState *bs, BDRVVHDXState *s, cpu_to_le64s(&s->bat[sinfo.bat_idx]); sector_num += s->sectors_per_block; } - ret = bdrv_pwrite(bs, rt_bat->file_offset, s->bat, rt_bat->length); + ret = bdrv_pwrite(bs, file_offset, s->bat, length); if (ret < 0) { goto exit; } @@ -1626,6 +1634,8 @@ static int vhdx_create_new_region_table(BlockDriverState *bs, int ret = 0; uint32_t offset = 0; void *buffer = NULL; + uint64_t bat_file_offset; + uint32_t bat_length; BDRVVHDXState *s = NULL; VHDXRegionTableHeader *region_table; VHDXRegionTableEntry *rt_bat; @@ -1674,19 +1684,26 @@ static int vhdx_create_new_region_table(BlockDriverState *bs, rt_metadata->length = 1 * MiB; /* min size, and more than enough */ *metadata_offset = rt_metadata->file_offset; + bat_file_offset = rt_bat->file_offset; + bat_length = rt_bat->length; + + vhdx_region_header_le_export(region_table); + vhdx_region_entry_le_export(rt_bat); + vhdx_region_entry_le_export(rt_metadata); + vhdx_update_checksum(buffer, VHDX_HEADER_BLOCK_SIZE, offsetof(VHDXRegionTableHeader, checksum)); /* The region table gives us the data we need to create the BAT, * so do that now */ - ret = vhdx_create_bat(bs, s, image_size, type, use_zero_blocks, rt_bat); + ret = vhdx_create_bat(bs, s, image_size, type, use_zero_blocks, + bat_file_offset, bat_length); + if (ret < 0) { + goto exit; + } /* Now write out the region headers to disk */ - vhdx_region_header_le_export(region_table); - vhdx_region_entry_le_export(rt_bat); - vhdx_region_entry_le_export(rt_metadata); - ret = bdrv_pwrite(bs, VHDX_REGION_TABLE_OFFSET, buffer, VHDX_HEADER_BLOCK_SIZE); if (ret < 0) { |