@@ -66,6 +66,8 @@ type 1
granularity_bits 15
name_size 8
extra_data_size 0
+Bitmap table type size offset
+0 serialized 65536 10092544
Bitmap name bitmap-2
bitmap_table_offset 0x9c0000
@@ -75,4 +77,6 @@ type 1
granularity_bits 16
name_size 8
extra_data_size 0
+Bitmap table type size offset
+0 all-zeroes 0 0
@@ -175,6 +175,10 @@ class Qcow2BitmapDirEntry(Qcow2Struct):
entry_raw_size = self.bitmap_dir_entry_raw_size()
padding = ((entry_raw_size + 7) & ~7) - entry_raw_size
fd.seek(padding, 1)
+ self.bitmap_table = Qcow2BitmapTable(fd=fd,
+ offset=self.bitmap_table_offset,
+ nb_entries=self.bitmap_table_size,
+ cluster_size=self.cluster_size)
def bitmap_dir_entry_raw_size(self):
return struct.calcsize(self.fmt) + self.name_size + \
@@ -183,6 +187,52 @@ class Qcow2BitmapDirEntry(Qcow2Struct):
def dump(self):
print(f'{"Bitmap name":<25} {self.name}')
super(Qcow2BitmapDirEntry, self).dump()
+ self.bitmap_table.dump()
+
+
+class Qcow2BitmapTableEntry(Qcow2Struct):
+
+ fields = (
+ ('u64', '{}', 'entry'),
+ )
+
+ BME_TABLE_ENTRY_RESERVED_MASK = 0xff000000000001fe
+ BME_TABLE_ENTRY_OFFSET_MASK = 0x00fffffffffffe00
+ BME_TABLE_ENTRY_FLAG_ALL_ONES = 1
+
+ def __init__(self, fd):
+ super().__init__(fd=fd)
+ self.reserved = self.entry & self.BME_TABLE_ENTRY_RESERVED_MASK
+ self.offset = self.entry & self.BME_TABLE_ENTRY_OFFSET_MASK
+ if self.offset:
+ if self.entry & self.BME_TABLE_ENTRY_FLAG_ALL_ONES:
+ self.type = 'invalid'
+ else:
+ self.type = 'serialized'
+ elif self.entry & self.BME_TABLE_ENTRY_FLAG_ALL_ONES:
+ self.type = 'all-ones'
+ else:
+ self.type = 'all-zeroes'
+
+
+class Qcow2BitmapTable:
+
+ def __init__(self, fd, offset, nb_entries, cluster_size):
+ self.cluster_size = cluster_size
+ position = fd.tell()
+ fd.seek(offset)
+ self.entries = [Qcow2BitmapTableEntry(fd) for _ in range(nb_entries)]
+ fd.seek(position)
+
+ def dump(self):
+ bitmap_table = enumerate(self.entries)
+ print(f'{"Bitmap table":<14} {"type":<15} {"size":<12} {"offset"}')
+ for i, entry in bitmap_table:
+ if entry.type == 'serialized':
+ size = self.cluster_size
+ else:
+ size = 0
+ print(f'{i:<14} {entry.type:<15} {size:<12} {entry.offset}')
QCOW2_EXT_MAGIC_BITMAPS = 0x23852875