Module `refinery.units.crypto.cipher.tea`

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#!/usr/bin/env python3
# -*- coding: utf-8 -*-
from __future__ import annotations

from abc import abstractmethod
from typing import List, Iterable, Sequence, Optional

from refinery.units.crypto.cipher import StandardBlockCipherUnit, Arg
from refinery.lib.crypto import BlockCipher, BlockCipherFactory, CipherInterface, BufferType, CipherMode
from refinery.lib.chunks import pack, unpack


class TEABase(BlockCipher):

    block_size = 8
    key_size = {16}
    derived_key: List[int]
    big_endian: bool

    def __init__(
        self,
        key: BufferType, mode: Optional[CipherMode],
        big_endian: bool = False
    ):
        self.big_endian = big_endian
        super().__init__(key, mode)

    @property
    def key(self):
        return self.derived_key

    @key.setter
    def key(self, key):
        self.derived_key = unpack(key, 4, self.big_endian)

    @abstractmethod
    def tea_encrypt(self, key: Sequence[int], block: Iterable[int]):
        pass

    def block_encrypt(self, data):
        be = self.big_endian
        blocks = list(unpack(data, 4, be))
        blocks = self.tea_encrypt(self.derived_key, blocks)
        return pack(blocks, 4, be)

    @abstractmethod
    def tea_decrypt(self, key: Sequence[int], block: Iterable[int]):
        pass

    def block_decrypt(self, data):
        be = self.big_endian
        blocks = list(unpack(data, 4, be))
        blocks = self.tea_decrypt(self.derived_key, blocks)
        return pack(blocks, 4, be)


class TEAWithRounds(TEABase):
    rounds: int

    def __init__(self, key, mode, rounds: int = 32, big_endian: bool = False):
        super().__init__(key, mode, big_endian)
        self.rounds = rounds


class TEA(TEAWithRounds):
    """
    The TEA cipher.
    """
    def tea_encrypt(self, key: Sequence[int], block: Sequence[int]):
        k0, k1, k2, k3 = key
        v0, v1 = block
        carry = 0
        delta = 0x9E3779B9
        for _ in range(self.rounds):
            carry = (carry + delta) & 0xFFFFFFFF
            v0 = v0 + (((v1 << 4) + k0) ^ (v1 + carry) ^ (v1 >> 5) + k1) & 0xFFFFFFFF
            v1 = v1 + (((v0 << 4) + k2) ^ (v0 + carry) ^ (v0 >> 5) + k3) & 0xFFFFFFFF
        return (v0, v1)

    def tea_decrypt(self, key: Sequence[int], block: Sequence[int]):
        rounds = self.rounds
        k0, k1, k2, k3 = key
        v0, v1 = block
        delta = 0x9E3779B9
        carry = (delta * rounds) & 0xFFFFFFFF
        for _ in range(rounds):
            v1 = v1 - (((v0 << 4) + k2) ^ (v0 + carry) ^ (v0 >> 5) + k3) & 0xFFFFFFFF
            v0 = v0 - (((v1 << 4) + k0) ^ (v1 + carry) ^ (v1 >> 5) + k1) & 0xFFFFFFFF
            carry = (carry - delta) & 0xFFFFFFFF
        return (v0, v1)


class TEAUnit(StandardBlockCipherUnit):
    def __init__(
        self, key, iv=b'', padding=None, mode=None, raw=False,
        swap: Arg.Switch('-s', help='Decode blocks as big endian rather than little endian.') = False,
        rounds: Arg.Number('-k', help='Specify the number of rounds, {default} by default.') = 32,
        **more
    ):
        super().__init__(key, iv, padding=padding, mode=mode, raw=raw, swap=swap, rounds=rounds, **more)

    @property
    def block_size(self):
        return 8

    def _new_cipher(self, **optionals) -> CipherInterface:
        return super()._new_cipher(
            big_endian=self.args.swap, rounds=self.args.rounds, **optionals)


class tea(TEAUnit, cipher=BlockCipherFactory(TEA)):
    """
    TEA encryption and decryption.
    """

Classes

class TEABase (key, mode, big_endian=False)

Abstract base class for refinery's block cipher interface.

Expand source code Browse git

class TEABase(BlockCipher):

    block_size = 8
    key_size = {16}
    derived_key: List[int]
    big_endian: bool

    def __init__(
        self,
        key: BufferType, mode: Optional[CipherMode],
        big_endian: bool = False
    ):
        self.big_endian = big_endian
        super().__init__(key, mode)

    @property
    def key(self):
        return self.derived_key

    @key.setter
    def key(self, key):
        self.derived_key = unpack(key, 4, self.big_endian)

    @abstractmethod
    def tea_encrypt(self, key: Sequence[int], block: Iterable[int]):
        pass

    def block_encrypt(self, data):
        be = self.big_endian
        blocks = list(unpack(data, 4, be))
        blocks = self.tea_encrypt(self.derived_key, blocks)
        return pack(blocks, 4, be)

    @abstractmethod
    def tea_decrypt(self, key: Sequence[int], block: Iterable[int]):
        pass

    def block_decrypt(self, data):
        be = self.big_endian
        blocks = list(unpack(data, 4, be))
        blocks = self.tea_decrypt(self.derived_key, blocks)
        return pack(blocks, 4, be)

Ancestors

Subclasses

TEAWithRounds
XXTEA

Class variables

var derived_key
var big_endian

Instance variables

var key

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@property
def key(self):
    return self.derived_key

Methods

def tea_encrypt(self, key, block)

Expand source code Browse git

@abstractmethod
def tea_encrypt(self, key: Sequence[int], block: Iterable[int]):
    pass

def tea_decrypt(self, key, block)

Expand source code Browse git

@abstractmethod
def tea_decrypt(self, key: Sequence[int], block: Iterable[int]):
    pass

Inherited members

BlockCipher:
- block_decrypt
- block_encrypt
- decrypt
- encrypt
CipherInterface:
- block_size
- key_size

class TEAWithRounds (key, mode, rounds=32, big_endian=False)

Abstract base class for refinery's block cipher interface.

Expand source code Browse git

class TEAWithRounds(TEABase):
    rounds: int

    def __init__(self, key, mode, rounds: int = 32, big_endian: bool = False):
        super().__init__(key, mode, big_endian)
        self.rounds = rounds

Ancestors

Subclasses

TEA
XTEA

Class variables

var rounds

Inherited members

TEABase:
- block_decrypt
- block_encrypt
- decrypt
- encrypt
CipherInterface:
- block_size
- key_size

class TEA (key, mode, rounds=32, big_endian=False)

The TEA cipher.

Expand source code Browse git

class TEA(TEAWithRounds):
    """
    The TEA cipher.
    """
    def tea_encrypt(self, key: Sequence[int], block: Sequence[int]):
        k0, k1, k2, k3 = key
        v0, v1 = block
        carry = 0
        delta = 0x9E3779B9
        for _ in range(self.rounds):
            carry = (carry + delta) & 0xFFFFFFFF
            v0 = v0 + (((v1 << 4) + k0) ^ (v1 + carry) ^ (v1 >> 5) + k1) & 0xFFFFFFFF
            v1 = v1 + (((v0 << 4) + k2) ^ (v0 + carry) ^ (v0 >> 5) + k3) & 0xFFFFFFFF
        return (v0, v1)

    def tea_decrypt(self, key: Sequence[int], block: Sequence[int]):
        rounds = self.rounds
        k0, k1, k2, k3 = key
        v0, v1 = block
        delta = 0x9E3779B9
        carry = (delta * rounds) & 0xFFFFFFFF
        for _ in range(rounds):
            v1 = v1 - (((v0 << 4) + k2) ^ (v0 + carry) ^ (v0 >> 5) + k3) & 0xFFFFFFFF
            v0 = v0 - (((v1 << 4) + k0) ^ (v1 + carry) ^ (v1 >> 5) + k1) & 0xFFFFFFFF
            carry = (carry - delta) & 0xFFFFFFFF
        return (v0, v1)

Ancestors

Class variables

var rounds

Methods

def tea_encrypt(self, key, block)

Expand source code Browse git

def tea_encrypt(self, key: Sequence[int], block: Sequence[int]):
    k0, k1, k2, k3 = key
    v0, v1 = block
    carry = 0
    delta = 0x9E3779B9
    for _ in range(self.rounds):
        carry = (carry + delta) & 0xFFFFFFFF
        v0 = v0 + (((v1 << 4) + k0) ^ (v1 + carry) ^ (v1 >> 5) + k1) & 0xFFFFFFFF
        v1 = v1 + (((v0 << 4) + k2) ^ (v0 + carry) ^ (v0 >> 5) + k3) & 0xFFFFFFFF
    return (v0, v1)

def tea_decrypt(self, key, block)

Expand source code Browse git

def tea_decrypt(self, key: Sequence[int], block: Sequence[int]):
    rounds = self.rounds
    k0, k1, k2, k3 = key
    v0, v1 = block
    delta = 0x9E3779B9
    carry = (delta * rounds) & 0xFFFFFFFF
    for _ in range(rounds):
        v1 = v1 - (((v0 << 4) + k2) ^ (v0 + carry) ^ (v0 >> 5) + k3) & 0xFFFFFFFF
        v0 = v0 - (((v1 << 4) + k0) ^ (v1 + carry) ^ (v1 >> 5) + k1) & 0xFFFFFFFF
        carry = (carry - delta) & 0xFFFFFFFF
    return (v0, v1)

Inherited members

TEAWithRounds:
- block_decrypt
- block_encrypt
- block_size
- decrypt
- encrypt
- key_size

class TEAUnit (key, iv=b'', padding=None, mode=None, raw=False, swap=False, rounds=32, **more)

Expand source code Browse git

class TEAUnit(StandardBlockCipherUnit):
    def __init__(
        self, key, iv=b'', padding=None, mode=None, raw=False,
        swap: Arg.Switch('-s', help='Decode blocks as big endian rather than little endian.') = False,
        rounds: Arg.Number('-k', help='Specify the number of rounds, {default} by default.') = 32,
        **more
    ):
        super().__init__(key, iv, padding=padding, mode=mode, raw=raw, swap=swap, rounds=rounds, **more)

    @property
    def block_size(self):
        return 8

    def _new_cipher(self, **optionals) -> CipherInterface:
        return super()._new_cipher(
            big_endian=self.args.swap, rounds=self.args.rounds, **optionals)

Ancestors

Subclasses

Instance variables

var block_size

Expand source code Browse git

@property
def block_size(self):
    return 8

Inherited members

StandardBlockCipherUnit:
- Arg
- assemble
- filter
- finish
- handles
- is_quiet
- labelled
- leniency
- log_debug
- log_detach
- log_fail
- log_info
- log_level
- log_warn
- nozzle
- process
- read
- read1
- reverse
- run
- source
- superinit

class tea (key, iv=b'', padding=None, mode=None, raw=False, swap=False, rounds=32)

TEA encryption and decryption.

Expand source code Browse git

class tea(TEAUnit, cipher=BlockCipherFactory(TEA)):
    """
    TEA encryption and decryption.
    """

Ancestors

Class variables

var block_size
var key_size

Inherited members

TEAUnit:
- Arg
- assemble
- filter
- finish
- handles
- is_quiet
- labelled
- leniency
- log_debug
- log_detach
- log_fail
- log_info
- log_level
- log_warn
- nozzle
- process
- read
- read1
- reverse
- run
- source
- superinit