# -*- coding: utf-8 -*-
#
# ===================================================================
# The contents of this file are dedicated to the public domain. To
# the extent that dedication to the public domain is not available,
# everyone is granted a worldwide, perpetual, royalty-free,
# non-exclusive license to exercise all rights associated with the
# contents of this file for any purpose whatsoever.
# No rights are reserved.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
# BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
# ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
# CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
# ===================================================================
from Cryptodome.Util.py3compat import bord
from Cryptodome.Util._raw_api import (load_pycryptodome_raw_lib,
VoidPointer, SmartPointer,
create_string_buffer,
get_raw_buffer, c_size_t,
c_uint8_ptr)
from Cryptodome.Hash.keccak import _raw_keccak_lib
class SHA3_512_Hash(object):
"""A SHA3-512 hash object.
Do not instantiate directly.
Use the :func:`new` function.
:ivar oid: ASN.1 Object ID
:vartype oid: string
:ivar digest_size: the size in bytes of the resulting hash
:vartype digest_size: integer
"""
# The size of the resulting hash in bytes.
digest_size = 64
# ASN.1 Object ID
oid = "2.16.840.1.101.3.4.2.10"
def __init__(self, data, update_after_digest):
self._update_after_digest = update_after_digest
self._digest_done = False
state = VoidPointer()
result = _raw_keccak_lib.keccak_init(state.address_of(),
c_size_t(self.digest_size * 2),
0x06)
if result:
raise ValueError("Error %d while instantiating SHA-3/512"
% result)
self._state = SmartPointer(state.get(),
_raw_keccak_lib.keccak_destroy)
if data:
self.update(data)
def update(self, data):
"""Continue hashing of a message by consuming the next chunk of data.
Args:
data (byte string/byte array/memoryview): The next chunk of the message being hashed.
"""
if self._digest_done and not self._update_after_digest:
raise TypeError("You can only call 'digest' or 'hexdigest' on this object")
result = _raw_keccak_lib.keccak_absorb(self._state.get(),
c_uint8_ptr(data),
c_size_t(len(data)))
if result:
raise ValueError("Error %d while updating SHA-3/512"
% result)
return self
def digest(self):
"""Return the **binary** (non-printable) digest of the message that has been hashed so far.
:return: The hash digest, computed over the data processed so far.
Binary form.
:rtype: byte string
"""
self._digest_done = True
bfr = create_string_buffer(self.digest_size)
result = _raw_keccak_lib.keccak_digest(self._state.get(),
bfr,
c_size_t(self.digest_size))
if result:
raise ValueError("Error %d while instantiating SHA-3/512"
% result)
self._digest_value = get_raw_buffer(bfr)
return self._digest_value
def hexdigest(self):
"""Return the **printable** digest of the message that has been hashed so far.
:return: The hash digest, computed over the data processed so far.
Hexadecimal encoded.
:rtype: string
"""
return "".join(["%02x" % bord(x) for x in self.digest()])
def new(self):
"""Create a fresh SHA3-512 hash object."""
return type(self)(None, self._update_after_digest)
def new(*args, **kwargs):
"""Create a new hash object.
Args:
data (byte string/byte array/memoryview):
The very first chunk of the message to hash.
It is equivalent to an early call to :meth:`update`.
update_after_digest (boolean):
Whether :meth:`digest` can be followed by another :meth:`update`
(default: ``False``).
:Return: A :class:`SHA3_512_Hash` hash object
"""
data = kwargs.pop("data", None)
update_after_digest = kwargs.pop("update_after_digest", False)
if len(args) == 1:
if data:
raise ValueError("Initial data for hash specified twice")
data = args[0]
if kwargs:
raise TypeError("Unknown parameters: " + str(kwargs))
return SHA3_512_Hash(data, update_after_digest)
# The size of the resulting hash in bytes.
digest_size = SHA3_512_Hash.digest_size