/
decode.py
executable file
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/
decode.py
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#!/usr/bin/env python3
# Intel iAPX 432 image decoder
# Copyright 2016, 2017 Eric Smith <spacewar@gmail.com>
# This program is free software: you can redistribute it and/or modify
# it under the terms of version 3 of the GNU General Public License
# as published by the Free Software Foundation.
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
import argparse
import attr
from bitarray import bitarray
import xml.etree.ElementTree
from collections import OrderedDict
from allocation import Allocation
from arch import Arch
class ObjectBuilderBase:
def load_from_image(self, image, offset):
for field in attr.fields(self.__class__):
name = field.name
lsb = field.metadata['lsb']
width = field.metadata['width']
# print('loading', name, lsb, width)
field_bit_offset = 0
image_byte_offset = offset + (lsb // 8)
image_bit_offset = lsb % 8
value = 0
while width > 0:
if image_bit_offset + width < 8:
bits_from_byte = width
else:
bits_from_byte = 8 - image_bit_offset
# print('image_byte_offset:', image_byte_offset,
# 'image_bit_offset:', image_bit_offset)
byte = image[image_byte_offset] >> image_bit_offset
byte &= ((1 << bits_from_byte) - 1)
value |= (byte << field_bit_offset)
image_byte_offset += 1
image_bit_offset = 0
width -= bits_from_byte
field_bit_offset += bits_from_byte
# print('value:', value)
setattr(self, name, value)
return self
def object_builder_factory(class_name, *fields):
c = attr.make_class(name = class_name,
attrs = { name : attr.ib(default = None,
metadata = { 'lsb' : lsb,
'width': width })
for (name, lsb, width) in fields },
bases = (ObjectBuilderBase,))
return c
@attr.s(frozen = True)
class Coord:
dir_index = attr.ib()
seg_index = attr.ib()
AccessDescriptor = object_builder_factory('AccessDescriptor',
('dir_index', 20, 12),
('seg_index', 4, 12),
('valid', 0, 1),
('read', 18, 1),
('write', 19, 1),
('delete', 16, 1),
('heap', 17, 1),
('system_rights', 1, 3))
ObjectTableHeader = object_builder_factory('ObjectTableHeader',
('descriptor_type', 0, 5),
('preserved_5', 5, 11),
('reserved_16', 16, 4),
('free_index', 20, 12),
('reserved_32', 32, 4),
('end_index', 36, 12),
('fault_level_number', 48, 16),
('preserved_64', 64, 8),
('reclamation', 72, 1),
('level_number', 80, 16),
('storage_claim', 96, 32))
FreeDescriptor = object_builder_factory('FreeDescriptor',
('descriptor_type', 0, 5),
('preserved_5', 5, 11),
('reserved_16', 16, 4),
('free_index', 20, 12),
('preserved_32', 32, 32),
('preserved_64', 64, 8),
('reclamation', 72, 1),
('reserved_73', 73, 7),
('reserved_80', 80, 16),
('preserved_96', 96, 16))
StorageDescriptor = object_builder_factory('StorageDescriptor',
('descriptor_type', 0, 2),
('valid', 2, 1),
('base_type', 3, 1),
('storage_associated', 4, 1),
('io_lock', 5, 1),
('altered', 6, 1),
('accesed', 7, 1),
('segment_base', 8, 24),
('segment_length', 32, 16),
('preserved_48', 48, 16),
('system_type', 64, 5),
('processor_class', 69, 3),
('reclamation', 72, 1),
('reserved_73', 73, 7),
('level_number', 80, 16),
('dirty', 96, 1),
('preserved', 97, 31))
RefinementDescriptor = object_builder_factory('RefinementDescriptor',
('descriptor_type', 0, 2),
('valid', 2, 1),
('base_type', 3, 1),
('bypass_seg_index', 4, 12),
('preserved_16', 16, 4),
('bypass_dir_index', 20, 12),
('refinement_length', 32, 16),
('base_displacement', 48, 16),
('system_type', 64, 5),
('processor_class', 69, 3),
('reclamation', 72, 1),
('reserved_73', 73, 7),
('level_number', 80, 16),
('ad_preserved_96', 96, 4),
('ad_seg_index', 100, 12),
('ad_preserved_112', 112, 4),
('ad_dir_index', 116, 12))
TypeDescriptor = object_builder_factory('TypeDescriptor',
('descriptor_type', 0, 2),
('valid', 2, 1),
('private', 3, 1),
('preserved_4', 4, 32),
('tdo_seg_index', 36, 12),
('preserved_48', 48, 4),
('tdo_dir_index', 52, 12),
('preserved_64', 64, 8),
('reclamation', 72, 1),
('reserved_73', 73, 7),
('level', 80, 16),
('preserved_96', 96, 4),
('typed_obj_seg_index', 100, 12),
('preserved_112', 112, 4),
('typed_obj_dir_index', 116, 12))
InterconnectDescriptor = object_builder_factory('InterconnectDescriptor',
('descriptor_type', 0, 2),
('valid', 2, 1),
('descriptor_subtype', 3, 2),
('io_lock', 5, 1),
('altered', 6, 1),
('accessed', 7, 1),
('base_address', 8, 24),
('length', 32, 16),
('preserved_48', 48, 16),
('preserved_64', 64, 8),
('reclamation', 72, 1),
('reserved_73', 73, 7),
('level', 80, 16),
('preserved_96', 96, 16))
def parse_descriptor(image, offset):
v = image[offset]
descriptor = None
if v & 3 == 3:
descriptor = StorageDescriptor()
elif v & 3 == 2:
descriptor = RefinementDescriptor()
elif v & 3 == 1:
descriptor = TypeDescriptor()
elif v & 0x18 == 1:
descriptor = InterconnectDescriptor()
elif v & 0x18 == 0:
if v & 4 == 0:
descriptor = ObjectTableHeader()
else:
descriptor = FreeDescriptor()
if descriptor is None:
print('%06x: %02x' % (offset, v))
assert descriptor is not None
return descriptor.load_from_image(image, offset)
object_table = { }
class Segment:
_image = None
_segments = { }
_phys_mem_allocation = Allocation(1 << 24, "phys mem")
# Do not construct a Segment directly! Use the get_segment() method.
def __init__(self, image, base, length, coord, descriptor, temp = False, guard = False):
assert guard
if Segment._image is None:
assert image is not None
Segment._image = image
self.base = base
self.length = length
self.descriptor = descriptor
self.prefix = image[base-8:base]
self.ad_image = AccessDescriptor().load_from_image(self.prefix, 0)
#assert self.ad_image.dir_index == coord.dir_index
#assert self.ad_image.seg_index == coord.seg_index
if (self.ad_image.dir_index != coord.dir_index or
self.ad_image.seg_index != coord.seg_index):
print('ad image coords %d/%d don''t match expected coords %d/%d' % (self.ad_image.dir_index, self.ad_image.seg_index, coord.dir_index, coord.seg_index))
l2 = length
if l2 % 8 != 0:
l2 += 8 - (l2 % 8)
# assert not Segment._phys_mem_allocation.is_available(base - 8, l2)
#Segment._phys_mem_allocation._dump()
if not Segment._phys_mem_allocation.is_available(base - 8, l2):
print ('segment overlap!')
print('segment %d/%d at %06x %06x..%06x' % (coord.dir_index, coord.seg_index, base-8, base, base+length-1))
if not temp:
Segment._phys_mem_allocation.allocate(addr = base - 8,
size = l2,
data = self)
self.data = image[base:base+length]
@classmethod
def get_segment(cls, coord, image = None, base = None, length = None):
global object_table
if coord in Segment._segments:
return Segment._segments[coord]
if (coord.dir_index in object_table and
coord.seg_index < len(object_table[coord.dir_index])):
assert image is None and base is None and length is None
descriptor = object_table[coord.dir_index][coord.seg_index]
assert isinstance(descriptor, StorageDescriptor)
assert descriptor.valid
assert descriptor.storage_associated
segment = Segment(Segment._image,
descriptor.segment_base,
descriptor.segment_length + 1,
coord,
descriptor,
guard = True)
Segment._segments[coord] = segment
return segment
assert image is not None and base is not None and length is not None
#print('making temp segment w/ incomplete information')
return Segment(image,
base,
length,
coord,
None,
temp = True,
guard = True)
def get_descriptor(self):
return self.descriptor
def get_base_addr(self):
return self.base_addr
def get_length(self):
return self.length
def get_ad_image(self):
return self.ad_image
def __getitem__(self, key):
return self.data.__getitem__(key)
def parse_object_table(coord, ot_segment = None):
if ot_segment is None:
ot_segment = Segment.get_segment(coord)
offset = 0
header = parse_descriptor(ot_segment, offset)
assert isinstance(header, ObjectTableHeader)
table = [header]
#print('object table header', header)
index = 1
while (index * 16) < ot_segment.get_length():
descriptor = parse_descriptor(ot_segment, index * 16)
if coord == Coord(2, 2):
assert (isinstance(descriptor, StorageDescriptor) or
isinstance(descriptor, FreeDescriptor))
table.append(descriptor)
index += 1
# XXX validate free descriptor chain
return table
def parse_object_table_hierarchy(image):
global object_table
print('parsing object table directory')
otd_descriptor = parse_descriptor(image, 8 + 32)
assert isinstance(otd_descriptor, StorageDescriptor)
otd_segment = Segment.get_segment(Coord(2, 2),
image,
otd_descriptor.segment_base,
otd_descriptor.segment_length + 1)
otd = parse_object_table(Coord(2, 2), ot_segment = otd_segment)
object_table[2] = otd
# validate that descriptor points to object table directory
assert otd[2].segment_base == 8
for index in range(1, len(otd)):
ot_descriptor = otd[index]
if index > 2 and isinstance(ot_descriptor, FreeDescriptor):
continue
print('parsing object table %d' % index)
assert isinstance(ot_descriptor, StorageDescriptor)
object_table[index] = parse_object_table(Coord(2, index))
#if index == 1:
# check that object table only contains processor access segments and free descriptors
#elif index == 2:
# check that object table only contains object table data segments and free descriptors
#else:
# check that object table contains no processor access segments or object table data segments
def parse_image(image):
parse_object_table_hierarchy(image)
for dir_index in range(1, len(object_table)):
for seg_index in range(1, len(object_table[dir_index])):
descriptor = object_table[dir_index][seg_index]
if isinstance(descriptor, StorageDescriptor):
seg = Segment.get_segment(Coord(dir_index, seg_index))
else:
print('object %d/%d is' % (dir_index, seg_index), type(descriptor).__name__)
# offset = 0
# while offset < len(image):
# l = parse_segment(image, offset)
# offset += l
if __name__ == '__main__':
arg_parser = argparse.ArgumentParser(description='iAPX 432 Image Decoder')
arg_parser.add_argument('-a', '--arch',
type=argparse.FileType('r'),
default='iapx432-1.0.xml',
help='architecture definition (XML)')
arg_parser.add_argument('image_binary',
type=argparse.FileType('rb'),
nargs=1,
help='image binary input')
args = arg_parser.parse_args()
arch_tree = xml.etree.ElementTree.parse(args.arch)
args.arch.close()
arch = Arch(arch_tree)
image = args.image_binary[0].read()
args.image_binary[0].close()
parse_image(image)