Merge pull request #1049 from volatilityfoundation/issues/improve-mftscan

Simplify attribute object accesses

Author: ikelos

volatility3/framework/plugins/windows/mftscan.py

@@ -67,27 +67,17 @@ def _generator(self):
                 )
                 # We will update this on each pass in the next loop and use it as the new offset.
                 attr_base_offset = mft_record.FirstAttrOffset
-
-                attr_header = self.context.object(
-                    header_object,
+                attr = self.context.object(
+                    attribute_object,
                     offset=offset + attr_base_offset,
                     layer_name=layer.name,
                 )
 
                 # There is no field that has a count of Attributes
                 # Keep Attempting to read attributes until we get an invalid attr_header.AttrType
 
-                while attr_header.AttrType.is_valid_choice:
-                    vollog.debug(f"Attr Type: {attr_header.AttrType.lookup()}")
-
-                    # Offset past the headers to the attribute data
-                    attr_data_offset = (
-                        offset
-                        + attr_base_offset
-                        + self.context.symbol_space.get_type(
-                            attribute_object
-                        ).relative_child_offset("Attr_Data")
-                    )
+                while attr.Attr_Header.AttrType.is_valid_choice:
+                    vollog.debug(f"Attr Type: {attr.Attr_Header.AttrType.lookup()}")
 
                     # MFT Flags determine the file type or dir
                     # If we don't have a valid enum, coerce to hex so we can keep the record
@@ -97,19 +87,16 @@ def _generator(self):
                         mft_flag = hex(mft_record.Flags)
 
                     # Standard Information Attribute
-                    if attr_header.AttrType.lookup() == "STANDARD_INFORMATION":
-                        attr_data = self.context.object(
-                            si_object, offset=attr_data_offset, layer_name=layer.name
-                        )
-
+                    if attr.Attr_Header.AttrType.lookup() == "STANDARD_INFORMATION":
+                        attr_data = attr.Attr_Data.cast(si_object)
                         yield 0, (
-                            format_hints.Hex(attr_data_offset),
+                            format_hints.Hex(attr_data.vol.offset),
                             mft_record.get_signature(),
                             mft_record.RecordNumber,
                             mft_record.LinkCount,
                             mft_flag,
                             renderers.NotApplicableValue(),
-                            attr_header.AttrType.lookup(),
+                            attr.Attr_Header.AttrType.lookup(),
                             conversion.wintime_to_datetime(attr_data.CreationTime),
                             conversion.wintime_to_datetime(attr_data.ModifiedTime),
                             conversion.wintime_to_datetime(attr_data.UpdatedTime),
@@ -118,10 +105,8 @@ def _generator(self):
                         )
 
                     # File Name Attribute
-                    if attr_header.AttrType.lookup() == "FILE_NAME":
-                        attr_data = self.context.object(
-                            fn_object, offset=attr_data_offset, layer_name=layer.name
-                        )
+                    if attr.Attr_Header.AttrType.lookup() == "FILE_NAME":
+                        attr_data = attr.Attr_Data.cast(fn_object)
                         file_name = attr_data.get_full_name()
 
                         # If we don't have a valid enum, coerce to hex so we can keep the record
@@ -131,13 +116,13 @@ def _generator(self):
                             permissions = hex(attr_data.Flags)
 
                         yield 1, (
-                            format_hints.Hex(attr_data_offset),
+                            format_hints.Hex(attr_data.vol.offset),
                             mft_record.get_signature(),
                             mft_record.RecordNumber,
                             mft_record.LinkCount,
                             mft_flag,
                             permissions,
-                            attr_header.AttrType.lookup(),
+                            attr.Attr_Header.AttrType.lookup(),
                             conversion.wintime_to_datetime(attr_data.CreationTime),
                             conversion.wintime_to_datetime(attr_data.ModifiedTime),
                             conversion.wintime_to_datetime(attr_data.UpdatedTime),
@@ -146,14 +131,13 @@ def _generator(self):
                         )
 
                     # If there's no advancement the loop will never end, so break it now
-                    if attr_header.Length == 0:
+                    if attr.Attr_Header.Length == 0:
                         break
 
                     # Update the base offset to point to the next attribute
-                    attr_base_offset += attr_header.Length
-                    # Get the next attribute
-                    attr_header = self.context.object(
-                        header_object,
+                    attr_base_offset += attr.Attr_Header.Length
+                    attr = self.context.object(
+                        attribute_object,
                         offset=offset + attr_base_offset,
                         layer_name=layer.name,
                     )

volatility3/framework/symbols/windows/mft.json

@@ -230,21 +230,21 @@
                     "offset": 0,
                     "type": {
                         "kind": "struct",
-                        "name": "mft!ATTR_HEADER"
+                        "name": "ATTR_HEADER"
                     }
                 },
                 "Resident_Header": {
                     "offset": 16,
                     "type": {
                         "kind": "struct",
-                        "name": "mft!RESIDENT_HEADER"
+                        "name": "RESIDENT_HEADER"
                     }
                 },
                 "Attr_Data": {
                     "offset": 24,
                     "type": {
                         "kind": "struct",
-                        "name": "mft!ATTR_HEADER"
+                        "name": "ATTR_HEADER"
                     }
                 }
             },