def squeeze(self,
trits: MutableSequence[int],
offset: int = 0,
length: Optional[int] = None) -> None:
"""
Squeeze trits from the sponge into a buffer.
:param trits:
Buffer that will hold the squeezed trits.
IMPORTANT: If ``trits`` is too small, it will be extended!
:param offset:
Starting offset in ``trits``.
:param length:
Number of trits to squeeze from the sponge.
If not specified, defaults to :py:data:`TRIT_HASH_LENGTH`
(i.e., by default, we will try to squeeze exactly 1 hash).
"""
# Pad input if necessary, so that it can be divided evenly into
# hashes.
pad = ((len(trits) % TRIT_HASH_LENGTH) or TRIT_HASH_LENGTH)
trits += [0] * (TRIT_HASH_LENGTH - pad)
if length is None:
# By default, we will try to squeeze one hash.
# Note that this is different than ``absorb``.
length = len(trits) or TRIT_HASH_LENGTH
if length < 1:
raise with_context(
exc=ValueError('Invalid length passed to ``squeeze``.'),
context={
'trits': trits,
'offset': offset,
'length': length,
},
)
while offset < length:
unsigned_hash = self.k.digest()
signed_hash = [conv.convert_sign(b) for b in unsigned_hash]
trits_from_hash = conv.convertToTrits(signed_hash)
trits_from_hash[TRIT_HASH_LENGTH - 1] = 0
stop = min(TRIT_HASH_LENGTH, length - offset)
trits[offset:offset + stop] = trits_from_hash[0:stop]
flipped_bytes = bytearray(
conv.convert_sign(~b) for b in unsigned_hash)
# Reset internal state before feeding back in.
self.reset()
self.k.update(flipped_bytes)
offset += TRIT_HASH_LENGTH
def absorb(self,
trits: MutableSequence[int],
offset: int = 0,
length: Optional[int] = None) -> None:
"""
Absorb trits into the sponge from a buffer.
:param trits:
Buffer that contains the trits to absorb.
:param offset:
Starting offset in ``trits``.
:param length:
Number of trits to absorb. Defaults to ``len(trits)``.
"""
# Pad input if necessary, so that it can be divided evenly into
# hashes.
# Note that this operation creates a COPY of ``trits``; the
# incoming buffer is not modified!
pad = ((len(trits) % TRIT_HASH_LENGTH) or TRIT_HASH_LENGTH)
trits += [0] * (TRIT_HASH_LENGTH - pad)
if length is None:
length = len(trits)
if length < 1:
raise with_context(
exc=ValueError('Invalid length passed to ``absorb``.'),
context={
'trits': trits,
'offset': offset,
'length': length,
},
)
while offset < length:
stop = min(offset + TRIT_HASH_LENGTH, length)
# If we're copying over a full chunk, zero last trit.
if stop - offset == TRIT_HASH_LENGTH:
trits[stop - 1] = 0
signed_nums = conv.convertToBytes(trits[offset:stop])
# Convert signed bytes into their equivalent unsigned
# representation, in order to use Python's built-in bytes
# type.
unsigned_bytes = bytearray(
conv.convert_sign(b) for b in signed_nums)
self.k.update(unsigned_bytes)
offset += TRIT_HASH_LENGTH
def absorb(self, trits, offset=0, length=None):
# type: (MutableSequence[int], int, Optional[int]) -> None
"""
Absorb trits into the sponge from a buffer.
:param trits:
Buffer that contains the trits to absorb.
:param offset:
Starting offset in ``trits``.
:param length:
Number of trits to absorb. Defaults to ``len(trits)``.
"""
# Pad input if necessary, so that it can be divided evenly into
# hashes.
# Note that this operation creates a COPY of ``trits``; the
# incoming buffer is not modified!
pad = ((len(trits) % TRIT_HASH_LENGTH) or TRIT_HASH_LENGTH)
trits += [0] * (TRIT_HASH_LENGTH - pad)
if length is None:
length = len(trits)
if length < 1:
raise with_context(
exc = ValueError('Invalid length passed to ``absorb``.'),
context = {
'trits': trits,
'offset': offset,
'length': length,
},
)
while offset < length:
stop = min(offset + TRIT_HASH_LENGTH, length)
# If we're copying over a full chunk, zero last trit
if stop - offset == TRIT_HASH_LENGTH:
trits[stop - 1] = 0
signed_nums = conv.convertToBytes(trits[offset:stop])
# Convert signed bytes into their equivalent unsigned representation
# In order to use Python's built-in bytes type
unsigned_bytes = bytearray(conv.convert_sign(b) for b in signed_nums)
self.k.update(unsigned_bytes)
offset += TRIT_HASH_LENGTH
def squeeze(self, trits, offset=0, length=None):
# type: (MutableSequence[int], int, Optional[int]) -> None
"""
Squeeze trits from the sponge into a buffer.
:param trits:
Buffer that will hold the squeezed trits.
IMPORTANT: If ``trits`` is too small, it will be extended!
:param offset:
Starting offset in ``trits``.
:param length:
Number of trits to squeeze from the sponge.
If not specified, defaults to :py:data:`TRIT_HASH_LENGTH` (i.e.,
by default, we will try to squeeze exactly 1 hash).
"""
# Pad input if necessary, so that it can be divided evenly into
# hashes.
pad = ((len(trits) % TRIT_HASH_LENGTH) or TRIT_HASH_LENGTH)
trits += [0] * (TRIT_HASH_LENGTH - pad)
if length is None:
# By default, we will try to squeeze one hash.
# Note that this is different than ``absorb``.
length = len(trits) or TRIT_HASH_LENGTH
if length < 1:
raise with_context(
exc = ValueError('Invalid length passed to ``squeeze``.'),
context = {
'trits': trits,
'offset': offset,
'length': length,
},
)
while offset < length:
unsigned_hash = self.k.digest()
if PY2:
unsigned_hash = map(ord, unsigned_hash) # type: ignore
signed_hash = [conv.convert_sign(b) for b in unsigned_hash]
trits_from_hash = conv.convertToTrits(signed_hash)
trits_from_hash[TRIT_HASH_LENGTH - 1] = 0
stop = min(TRIT_HASH_LENGTH, length-offset)
trits[offset:offset+stop] = trits_from_hash[0:stop]
flipped_bytes = bytearray(conv.convert_sign(~b) for b in unsigned_hash)
# Reset internal state before feeding back in
self.reset()
self.k.update(flipped_bytes)
offset += TRIT_HASH_LENGTH