Add in limited support for Internal Areas

The code as is does not support printing or defining internal areas.
This patch adds basic support for doing this.

The contents of the internal area are defined by a list of hex numbers as
shown below:

InternalUse:
  data: 01 02 03 04 ab cd ef

The size of the internal area is set to the recommended 72 by default.
It can be changed by using the --internal-area-size command line arg.
The data given  will be padded with 0xff or truncated to fit this
length.  Note that byte 0 of the internal area is mandated to be a '1'
(see section 9 of the FRU spec), and that is included in the size.

When dumping, since there is no length field in the internal area, it
just takes the start of the next section (if present) as the size to
dump.

Author: djmsip

README.md

@@ -20,7 +20,7 @@ pip3 install git+https://github.com/MicroTCA-Tech-Lab/frugy
 $ frugy --help
 usage: frugy [-h] [--version] [-o OUTPUT] [-w] [-r] [-d]
              [-e EEPROM_SIZE] [-s SET] [-t] [-b] [-c] [-l [LIST]]
-             [-v VERBOSITY]
+             [-v VERBOSITY] [--internal-area-size SIZE]
              [srcfile]
 
 FRU Generator YAML

frugy/areas.py

@@ -10,7 +10,7 @@
 #                                                                         #
 ###########################################################################
 
-from frugy.types import FruAreaVersioned, FruAreaSized, FixedField, StringField, StringField, bin2hex_helper, CustomStringArray
+from frugy.types import FruAreaInternalUse, FruAreaVersioned, FruAreaSized, FixedField, StringField, StringField, bin2hex_helper, CustomStringArray, BytearrayField
 from frugy.fru_registry import FruRecordType, rec_register
 from datetime import datetime, timedelta
 import logging
@@ -152,3 +152,12 @@ class ProductInfo(FruAreaSized):
         ('fru_file_id', StringField),
         ('custom_info_fields', CustomStringArray),
     ]
+
+
+@ipmi_area
+class InternalUse(FruAreaInternalUse):
+    ''' Platform Management FRU Information Storage Definition, Table 9-1 '''
+
+    _schema = [
+        ('data', BytearrayField),
+    ]

frugy/cli.py

@@ -20,7 +20,7 @@
 from frugy.__init__ import __version__
 from frugy.fru import Fru
 from frugy.fru_registry import FruRecordType, rec_enumerate, rec_lookup_by_name, rec_info, schema_entry_info
-from frugy.types import FruAreaChecksummed
+from frugy.types import FruAreaChecksummed, FruAreaInternalUse
 from frugy.multirecords import MultirecordEntry
 
 
@@ -135,6 +135,11 @@ def main():
                         nargs='?',
                         help='list supported FRU records or schema of specified record'
                         )
+
+    parser.add_argument('--internal-area-size',
+                        type=int,
+                        help='set internal area size (including format byte), default is recommended 72 (only valid in write mode)'
+                        )
     parser.add_argument('-v', '--verbosity',
                         type=int,
                         help='set verbosity (0=quiet, 1=info, 2=debug)'
@@ -163,7 +168,7 @@ def main():
         parser.print_help(sys.stderr)
         sys.exit(1)
 
-    if read_mode and (args.eeprom_size is not None or args.set or args.timestamp):
+    if read_mode and (args.eeprom_size is not None or args.set or args.timestamp or args.internal_area_size):
         parser.print_help(sys.stderr)
         sys.exit(1)
 
@@ -173,6 +178,15 @@ def main():
     if read_mode and args.ignore_checksum_errors:
         FruAreaChecksummed.ignore_checksum_errors = True
 
+    if args.internal_area_size == None:
+        args.internal_area_size = 72 # Recommended size in FRU document
+    if args.internal_area_size % 8 != 0:
+        print("Internal area size must be a multiple of 8 bytes", file=sys.stderr)
+        sys.exit(1)
+    # In read mode, this isn't used, we always use the size of the section in
+    # the file since there is no length field.
+    FruAreaInternalUse.internal_area_size = args.internal_area_size
+
     outfile = args.output
     if args.dump:
         if outfile:

frugy/fru.py

@@ -11,7 +11,7 @@
 ###########################################################################
 
 from frugy import __version__
-from frugy.areas import CommonHeader, ChassisInfo, BoardInfo, ProductInfo
+from frugy.areas import CommonHeader, ChassisInfo, BoardInfo, ProductInfo, InternalUse
 from frugy.multirecords import MultirecordArea
 import frugy.multirecords_ipmi
 import frugy.multirecords_picmg
@@ -44,6 +44,7 @@ def import_log(msg):
 
 class Fru:
     _area_table_lookup = bidict({
+        'InternalUse': 'internal_use_offs',
         'ChassisInfo': 'chassis_info_offs',
         'BoardInfo': 'board_info_offs',
         'ProductInfo': 'product_info_offs',
@@ -59,6 +60,7 @@ def __init__(self, initdict=None):
 
     def factory(self, cls_name, cls_args=None):
         map = {
+            'InternalUse': InternalUse,
             'ChassisInfo': ChassisInfo,
             'BoardInfo': BoardInfo,
             'ProductInfo': ProductInfo,
@@ -101,13 +103,33 @@ def deserialize(self, input):
         import_log.str = ''
         self.areas = {}
         self.header.deserialize(input)
+
+        # The internal record does not have a length field in it,
+        # and it is just a byte array. So we have to find the start
+        # of the next record and slice the input on that boundary.
+        end_of_internal = 0;
+        internal_use_offset = 0
+        offset_list = []
+        for k, v in self.header.to_dict().items():
+            if v and k == 'internal_use_offs':
+                internal_use_offset = v
+            offset_list.append(v)
+        offset_list.sort()
+
+        if internal_use_offset != 0:
+            index = offset_list.index(internal_use_offset)
+            # Check it isn't the last on the list
+            if index != len(offset_list) - 1:
+                end_of_internal = offset_list[index + 1]
+
         for k, v in self.header.to_dict().items():
-            # Ignore "internal use area"
-            # TODO: Support it as opaque byte array?
-            if v and k != 'internal_use_offs':
+            if v:
                 obj_name = self._area_table_lookup.inverse[k]
                 obj = self.factory(obj_name)
-                obj.deserialize(input[v:])
+                if k == 'internal_use_offs' and end_of_internal != 0:
+                    obj.deserialize(input[v:end_of_internal])
+                else:
+                    obj.deserialize(input[v:])
                 self.areas[obj_name] = obj
 
     def load_yaml(self, fname):

frugy/types.py

@@ -694,6 +694,47 @@ def deserialize(self, input: bytearray):
         remainder = self._deserialize(input[1:])
         return self._verify_epilogue(input, len(input) - len(remainder))
 
+class FruAreaInternalUse(FruAreaBase):
+    ''' FRU Internal use area featuring a version field but no checksum, will
+    be padded to whatever internal area is specified'''
+
+    internal_area_size = 72
+
+    def __init__(self, initdict=None):
+        self._format_version = _format_version_default
+        super().__init__(initdict=initdict)
+
+    def _set_format_version(self, val):
+        self._format_version = val
+
+    def _get_format_version(self):
+        return self._format_version
+
+    def _prologue(self) -> bytearray:
+        ''' return data to prepend (format version) '''
+        return self._format_version.to_bytes(1, 'little')
+
+    def _epilogue(self, payload: bytearray) -> bytearray:
+        ''' return data to append, padded of zero bytes'''
+        numPadBytes, _ = _sizeAlign(len(payload), self.internal_area_size)
+        return b'\xff' * numPadBytes
+
+    def size_payload(self) -> int:
+        return self.internal_area_size
+
+    def size_total(self) -> int:
+        return self.internal_area_size
+
+    def serialize(self) -> bytearray:
+        payload = self._prologue()
+        body = self._serialize()
+        payload += body[:self.internal_area_size - 1]
+        return payload + self._epilogue(payload)
+
+    def deserialize(self, input: bytearray):
+        self._format_version = input[0]
+        return self._deserialize(input[1:])
+
 
 class FruAreaSized(FruAreaVersioned):
     ''' FRU area featuring version and length fields '''