pysha3 0.2.2

SHA-3 (Keccak) for Python 2.6 - 3.4

pysha3

SHA-3 wrapper (keccak) for Python. The package is a wrapper around the optimized reference implementation from http://keccak.noekeon.org/ . Only the optimizations for 32 and 64bit platforms are used. The optimized SSE and ARM assembly variants are ignored for now.

The module is a standalone version of the SHA-3 implemention of Python 3.4 (currently under development).

Usage

The sha3 module contains several constructors for hash objects with a PEP 247 compatible interface. The module provides sha3_228(), sha3_256(), sha3_384(), and sha3_512().

The sha3 module monkey patches the hashlib module . The monkey patch is automatically activated with the first import of the sha3 module. The hashlib module of Python 3.4 will support the four SHA-3 algorithms on all platforms. Therefore you shouldn’t use the sha3 module directly and rather go through the hashlib interface:

>>> import sys
>>> import hashlib
>>> if sys.version_info < (3, 4):
...    import sha3
>>> s = hashlib.new("sha3_512")
>>> s = hashlib.sha3_512() # alternative
>>> s.name
'sha3_512'
>>> s.digest_size
64
>>> s.update(b"data")
>>> s.hexdigest()
'1065aceeded3a5e4412e2187e919bffeadf815f5bd73d37fe00d384fe29f55f08462fdabe1007b993ce5b8119630e7db93101d9425d6e352e22ffe3dcb56b825'

Comments from sha3module header

The code is based on KeccakReferenceAndOptimized-3.2.zip from 29 May 2012.

The reference implementation is altered in this points:

• C++ comments are converted to ANSI C comments.

• All functions and globals are declared static.

• The typedef for UINT64 is commented out.

• brg_endian.h is removed.

• KeccakF-1600-opt[32|64]-settings.h are commented out

• Some unused functions are commented out to silence compiler warnings.

In order to avoid name clashes with other software I have to declare all Keccak functions and global data as static. The C code is directly included into this file in order to access the static functions.

Keccak can be tuned with several paramenters. I try to explain all options as far as I understand them. The reference implementation also contains assembler code for ARM platforms (NEON instructions).

Common

Unrolling

loop unrolling (24, 12, 8, 6, 4, 3, 2, 1)

UseBebigokimisa

lane complementing

64bit platforms

default settings of common options

Unrolling

24

UseBebigokimisa

enabled

Additional optimiation instructions (disabled by default):

UseSSE

use Stream SIMD extensions

UseOnlySIMD64

limit to 64bit instructions, otherwise 128bit

w/o UseOnlySIMD64

requires compiler argument -mssse3 or -mtune=core2 or better

UseMMX

use 64bit MMX instructions

UseXOP

use AMD’s eXtended Operations (128bit SSE extension)

When neither UseSSE, UseMMX nor UseXOP is configured, ROL64 (rotate left 64) is implemented as:

Windows

_rotl64()

UseSHLD

use shld (shift left) asm optimization

otherwise

shift and xor

UseBebigokimisa can’t be used in combination with UseSSE, UseMMX or UseXOP. UseOnlySIMD64 has no effect unless UseSSE is specified.

Tests have shown that UseSSE + UseOnlySIMD64 is about three to four times SLOWER than UseBebigokimisa. UseSSE and UseMMX are about two times slower. (tested by CH and AP)

32bit platforms

default settings of common options

Unrolling

2

UseBebigokimisa

disabled

UseSchedule

1

unknown

2

unknown

3 [default]

unknown, no UseBebigokimisa, Unrolling must be 2

UseInterleaveTables

use two 64k lookup tables for (de)interleaving (disabled by default)

Changelog

pysha3 0.2.2

Release date: 07-Oct-2012

• Re-add brg_endian.h to fix issue on Solaris (big endian platform)

pysha3 0.2.1

Release date: 06-Oct-2012

• fixed MANIFEST.in to include Makefile and tests.py

• added setup.py test command with hack for inplace builds

• enhanced README.txt and fixed its markup

pysha3 0.2

Release date: 06-Oct-2012

• Change directory struct to use the same directory layout as Python 3.4.

• Remove C++ comments from Keccak sources for ANSI C compatibility.

• Declare all Keccak functions and globals as static to avoid name clashes.

• Remove alias sha3() for sha3_512().

• Add block_size attribute. Keccak has a internal sponge size of 1600 bits.

• Release GIL around SHA3_update() calls.

• Monkey patch the hashlib module to support, e.g. hashlib.sha3_512() and hashlib.new(“sha3_512”)

• Release GIL around SHA3_update() when the data exceeds a certain size.

• Fix build on platforms with an unsigned 64bit integer type (uint64_t). The module falls back to 32bit implementation of Keccak with interleave tables.

pysha3 0.1

Release date: 04-Oct-2012

• first release

• based on KeccakReferenceAndOptimized-3.2.zip