def read_block(self, block, noauth=False):
'''Works only for data blocks, whereas for the trailer blocks reads the ACL only'''
if not noauth: self.auth(block, READ)
data = mifare.read(self.reader, block)
sector = self.block2sector(block)
tblock = self.trailer_block(sector)
if block == tblock:
data = self.fix_trailer_block(sector, data)
return data
def read_block(self, block, noauth=False):
'''Works only for data blocks, whereas for the trailer blocks reads the ACL only'''
if not noauth: self.auth(block, READ)
data = mifare.read(self.reader, block)
sector = self.block2sector(block)
tblock = self.trailer_block(sector)
if block == tblock:
data = self.fix_trailer_block(sector, data)
return data
def auth(self, block, access_type):
'''Authentication needs to be done once per sector. After successful authentication any
number of blocks from the sector can be read/written to.'''
# find out the sector we are going to access
sector = self.block2sector(block)
# only do the authentication if we have required keys loaded
if sector >= len(self._keys):
raise RuntimeError(
'Cannot unlock sector %d - no key for the sector provided!' %
(sector))
# check the access conditions for this data block
tblock = self.trailer_block(sector)
auth_key = 0
if sector in self._trailer_cache:
tdata = self._trailer_cache[sector]
else:
# we have read the trailer block, se have to authenticate to the sector anyway
if mifare.auth(self.reader, block, mifare.MC_AUTH_A,
self._keys[sector]['a'], self.uid()):
auth_key = 1
elif mifare.auth(self.reader, block, mifare.MC_AUTH_B,
self._keys[sector]['b'], self.uid()):
auth_key = 2
else:
raise RuntimeError('Cannot unlock sector %d' % (sector))
tdata = self._trailer_cache[sector] = mifare.read(
self.reader, tblock)
keya, access_cond, keyb = struct.unpack('6s4s6s', tdata)
access_cond = self._parse_acl(access_cond)
sblock = block % self.sector_size(sector)
# read or write access condition, see data_acl for data blocks and trailer_acl for the trailer block
auth_keys = access_cond[sblock][
access_type] if block != tblock else access_cond[sblock]['acl'][
access_type]
if auth_keys == 0:
raise RuntimeError("ACL denies %s on sector %d, block %d" %
(['reads', 'writes'][access_type], sector, i))
if not auth_keys & auth_key:
keytype = mifare.MC_AUTH_B if auth_keys == 2 else mifare.MC_AUTH_A
keyidx = 'a' if keytype == mifare.MC_AUTH_A else 'b'
if not mifare.auth(self.reader, block, keytype,
self._keys[sector][keyidx], self.uid()):
raise RuntimeError(
'Authentication of sector %d, block %d failed' %
(sector, i))
return True
def auth(self, block, access_type):
'''Authentication needs to be done once per sector. After successful authentication any
number of blocks from the sector can be read/written to.'''
# find out the sector we are going to access
sector = self.block2sector(block)
# only do the authentication if we have required keys loaded
if sector >= len(self._keys):
raise RuntimeError('Cannot unlock sector %d - no key for the sector provided!' % (sector))
# check the access conditions for this data block
tblock = self.trailer_block(sector)
auth_key = 0
if sector in self._trailer_cache:
tdata = self._trailer_cache[sector]
else:
# we have read the trailer block, se have to authenticate to the sector anyway
if mifare.auth(self.reader, block, mifare.MC_AUTH_A, self._keys[sector]['a'], self.uid()):
auth_key = 1
elif mifare.auth(self.reader, block, mifare.MC_AUTH_B, self._keys[sector]['b'], self.uid()):
auth_key = 2
else:
raise RuntimeError('Cannot unlock sector %d' % (sector))
tdata = self._trailer_cache[sector] = mifare.read(self.reader, tblock)
keya, access_cond, keyb = struct.unpack('6s4s6s', tdata)
access_cond = self._parse_acl(access_cond)
sblock = block % self.sector_size(sector)
# read or write access condition, see data_acl for data blocks and trailer_acl for the trailer block
auth_keys = access_cond[sblock][access_type] if block != tblock else access_cond[sblock]['acl'][access_type]
if auth_keys == 0:
raise RuntimeError("ACL denies %s on sector %d, block %d" % (['reads','writes'][access_type], sector, i))
if not auth_keys & auth_key:
keytype = mifare.MC_AUTH_B if auth_keys == 2 else mifare.MC_AUTH_A
keyidx = 'a' if keytype == mifare.MC_AUTH_A else 'b'
if not mifare.auth(self.reader, block, keytype, self._keys[sector][keyidx], self.uid()):
raise RuntimeError('Authentication of sector %d, block %d failed' % (sector, i))
return True
