def _parse_directory(self):
self.directory_bitmap = util.bitrange(self.directory_bits, (0, 1),
(1, 4))
self._parse_directory_bitmap()
directory_format_revision = util.bitrange(self.directory_bits, (1, 3),
(1, 0))
# Sector Chain Table
for x in range(0, self.shell.max_sectors - 3):
position = (16 + 5 * 8 *
self.shell.max_directory_entries) + self.shell.psi * x
entry_bits = self.directory_bits[position:position +
self.shell.psi].uint
self.sct[x + 1] = entry_bits
# Directory Entries
for x in range(1, self.shell.max_directory_entries):
position = 16 + 5 * 8 * x
entry_bits = self.directory_bits[position:position + 40]
# Skip entry empties
if entry_bits.uint == 0:
continue
entry = IPEDirectoryEntry(x, entry_bits, self.sct,
self.shell.max_sectors)
self.entries.append(entry)
# Cyclic Log
log_location = (16 + 5 * 8 * self.shell.max_directory_entries)
log = self.directory_bits[log_location:log_location + 40]
self.log = LogDirectoryEntry(log, self.sct, self.shell.max_sectors)
sequence_location = (16 + 5 * 8 * self.shell.max_directory_entries
) + self.shell.sctl_size * 8
self.sequence = self.directory_bits[
sequence_location:sequence_location + 8].uint
self.kid = self.directory_bits[sequence_location +
8:sequence_location + 12]
self.shell_iteration = self.directory_bits[sequence_location +
12:sequence_location +
16].uint
self.isamid = self.directory_bits[sequence_location +
16:sequence_location + 48]
def _parse_shell(self):
self.shell_length = util.bitrange(self.shell_bits, (0, 7), (0, 2)).uint
self.shell_bitmap = util.bitrange(self.shell_bits, (0, 1), (1, 4))
self._parse_shell_bitmap()
shell_format_revision = util.bitrange(self.shell_bits, (1, 3),
(1, 0)).hex
# Compact shells only contain four basic fields.
if self.shell_bitmap_type == self.TYPES.COMPACT:
FVC = util.bitrange(self.shell_bits, (2, 0), (2, 7)).hex
return
isrn_iin = util.bitrange(self.shell_bits, (2, 7), (4, 0))
isrn_oid = util.bitrange(self.shell_bits, (5, 7), (6, 0))
isrn_issn = util.bitrange(self.shell_bits, (7, 7), (10, 4))
isrn_chd = util.bitrange(self.shell_bits, (10, 3), (10, 0))
isrn = isrn_iin + isrn_oid + isrn_issn + isrn_chd
self.isrn = util.bcd_digits(isrn.bytes)
self.FVC = util.bitrange(self.shell_bits, (11, 7), (11, 0)).uint
self.KSC = util.bitrange(self.shell_bits, (12, 7), (12, 0)).uint
self.KVC = util.bitrange(self.shell_bits, (13, 7), (13, 0)).uint
expiry_bitrange = util.bitrange(self.shell_bits, (14, 5), (15, 0))
self.expiry = util.en1545_DATE_from(expiry_bitrange.uint)
self.sector_size = util.bitrange(self.shell_bits, (16, 7),
(16, 0)).uint
self.max_sectors = util.bitrange(self.shell_bits, (17, 7),
(17, 0)).uint
self.psi = len('{0:b}'.format(self.max_sectors - 1))
self.max_directory_entries = util.bitrange(self.shell_bits, (18, 7),
(18, 0)).uint
self.sctl_size = util.bitrange(self.shell_bits, (19, 7), (19, 0)).uint
if not self.shell_bitmap_mcrn:
SECRC = util.bitrange(self.shell_bits, (22, 7), (23, 0))
else:
# The Multi-application CM reference is padded with 0x and ends
# in a check digit. These aren't part of the reference number, so
# let's remove them.
mcrn = util.bitrange(self.shell_bits, (20, 7), (29, 0))
mcrn.replace('0xf', '')
self.mcrn = mcrn.hex[:-1]
SECRC = util.bitrange(self.shell_bits, (30, 7), (31, 0))