from allmydata.interfaces import BadWriteEnablerError
from allmydata.util import idlib, log
from allmydata.util.assertutil import precondition
+from allmydata.util.hashutil import constant_time_compare
from allmydata.storage.lease import LeaseInfo
from allmydata.storage.common import UnknownMutableContainerVersionError, \
DataTooLargeError
# 9 ?? n*92 extra leases
-assert struct.calcsize("L"), 4 # The struct module doc says that L's are 4 bytes in size.
-assert struct.calcsize("Q"), 8 # The struct module doc says that Q's are 8 bytes in size (at least with big-endian ordering).
+assert struct.calcsize(">L") == 4 # The struct module doc says that L's are 4 bytes in size.
+assert struct.calcsize(">Q") == 8 # The struct module doc says that Q's are 8 bytes in size (at least with big-endian ordering).
class MutableShareFile:
accepting_nodeids = set()
f = open(self.home, 'rb+')
for (leasenum,lease) in self._enumerate_leases(f):
- if lease.renew_secret == renew_secret:
+ if constant_time_compare(lease.renew_secret, renew_secret):
# yup. See if we need to update the owner time.
if new_expire_time > lease.expiration_time:
# yes
f = open(self.home, 'rb+')
for (leasenum,lease) in self._enumerate_leases(f):
accepting_nodeids.add(lease.nodeid)
- if lease.cancel_secret == cancel_secret:
+ if constant_time_compare(lease.cancel_secret, cancel_secret):
self._write_lease_record(f, leasenum, blank_lease)
modified += 1
else:
(real_write_enabler, write_enabler_nodeid) = \
self._read_write_enabler_and_nodeid(f)
f.close()
- if write_enabler != real_write_enabler:
+ # avoid a timing attack
+ #if write_enabler != real_write_enabler:
+ if not constant_time_compare(write_enabler, real_write_enabler):
# accomodate share migration by reporting the nodeid used for the
# old write enabler.
self.log(format="bad write enabler on SI %(si)s,"