fix SHARE_HASH_CHAIN_SIZE computation

This commit is contained in:
Brian Warner 2011-08-11 10:53:50 -07:00
parent dd23f265bf
commit eec428ba5f

View File

@ -548,10 +548,10 @@ MDMFOFFSETS_LENGTH = struct.calcsize(MDMFOFFSETS)
PRIVATE_KEY_SIZE = 1220
SIGNATURE_SIZE = 260
VERIFICATION_KEY_SIZE = 292
# We know we won't have more than 256 shares, and we know that we won't
# need to store more than lg 256 of them to validate, so that's our
# bound. We add 1 to the int cast to round to the next integer.
SHARE_HASH_CHAIN_SIZE = int(math.log(HASH_SIZE * 256)) + 1
# We know we won't have more than 256 shares, and we know that we won't need
# to store more than ln2(256) hash-chain nodes to validate, so that's our
# bound. Each node requires 2 bytes of node-number plus 32 bytes of hash.
SHARE_HASH_CHAIN_SIZE = (2+HASH_SIZE)*mathutil.log_ceil(256, 2)
class MDMFSlotWriteProxy:
implements(IMutableSlotWriter)