FM / Cipher

/opt/imh-python/lib/python3.9/site-packages/Crypto/Cipher/

/opt/imh-python/lib/python3.9/site-packages/Crypto/Cipher

Name	Size	Mode	Actions
__pycache__/	-	0755	rm
AES.py	9541	0644	edit dl rm
AES.pyi	1343	0644	edit dl rm
ARC2.py	7010	0644	edit dl rm
ARC2.pyi	954	0644	edit dl rm
ARC4.py	5152	0644	edit dl rm
ARC4.pyi	431	0644	edit dl rm
Blowfish.py	5964	0644	edit dl rm
Blowfish.pyi	990	0644	edit dl rm
CAST.py	6071	0644	edit dl rm
CAST.pyi	955	0644	edit dl rm
ChaCha20.py	10734	0644	edit dl rm
ChaCha20.pyi	762	0644	edit dl rm
ChaCha20_Poly1305.py	11529	0644	edit dl rm
ChaCha20_Poly1305.pyi	1068	0644	edit dl rm
DES.py	5947	0644	edit dl rm
DES.pyi	935	0644	edit dl rm
DES3.py	6925	0644	edit dl rm
DES3.pyi	1005	0644	edit dl rm
PKCS1_OAEP.py	8824	0644	edit dl rm
PKCS1_OAEP.pyi	1179	0644	edit dl rm
PKCS1_v1_5.py	7943	0644	edit dl rm
PKCS1_v1_5.pyi	567	0644	edit dl rm
Salsa20.py	6349	0644	edit dl rm
Salsa20.pyi	744	0644	edit dl rm
_ARC4.cpython-39-x86_64-linux-gnu.so	8072	0755	edit dl rm
_chacha20.cpython-39-x86_64-linux-gnu.so	11024	0755	edit dl rm
_EKSBlowfish.py	5205	0644	edit dl rm
_EKSBlowfish.pyi	266	0644	edit dl rm
_mode_cbc.py	10951	0644	edit dl rm
_mode_cbc.pyi	687	0644	edit dl rm
_mode_ccm.py	24444	0644	edit dl rm
_mode_ccm.pyi	1600	0644	edit dl rm
_mode_cfb.py	10801	0644	edit dl rm
_mode_cfb.pyi	727	0644	edit dl rm
_mode_ctr.py	15880	0644	edit dl rm
_mode_ctr.pyi	800	0644	edit dl rm
_mode_eax.py	14511	0644	edit dl rm
_mode_eax.pyi	1545	0644	edit dl rm
_mode_ecb.py	8210	0644	edit dl rm
_mode_ecb.pyi	592	0644	edit dl rm
_mode_gcm.py	21358	0644	edit dl rm
_mode_gcm.pyi	1541	0644	edit dl rm
_mode_ocb.py	19794	0644	edit dl rm
_mode_ocb.pyi	1231	0644	edit dl rm
_mode_ofb.py	10281	0644	edit dl rm
_mode_ofb.pyi	691	0644	edit dl rm
_mode_openpgp.py	7053	0644	edit dl rm
_mode_openpgp.pyi	556	0644	edit dl rm
_mode_siv.py	14062	0644	edit dl rm
_mode_siv.pyi	1261	0644	edit dl rm
_raw_aes.cpython-39-x86_64-linux-gnu.so	26816	0755	edit dl rm
_raw_aesni.cpython-39-x86_64-linux-gnu.so	11648	0755	edit dl rm
_raw_arc2.cpython-39-x86_64-linux-gnu.so	10528	0755	edit dl rm
_raw_blowfish.cpython-39-x86_64-linux-gnu.so	13568	0755	edit dl rm
_raw_cast.cpython-39-x86_64-linux-gnu.so	19864	0755	edit dl rm
_raw_cbc.cpython-39-x86_64-linux-gnu.so	8672	0755	edit dl rm
_raw_cfb.cpython-39-x86_64-linux-gnu.so	8928	0755	edit dl rm
_raw_ctr.cpython-39-x86_64-linux-gnu.so	9200	0755	edit dl rm
_raw_des.cpython-39-x86_64-linux-gnu.so	45120	0755	edit dl rm
_raw_des3.cpython-39-x86_64-linux-gnu.so	45408	0755	edit dl rm
_raw_ecb.cpython-39-x86_64-linux-gnu.so	6528	0755	edit dl rm
_raw_eksblowfish.cpython-39-x86_64-linux-gnu.so	18888	0755	edit dl rm
_raw_ocb.cpython-39-x86_64-linux-gnu.so	11456	0755	edit dl rm
_raw_ofb.cpython-39-x86_64-linux-gnu.so	7496	0755	edit dl rm
_Salsa20.cpython-39-x86_64-linux-gnu.so	8824	0755	edit dl rm
__init__.py	2844	0644	edit dl rm
__init__.pyi	0	0644	edit dl rm

Edit: /opt/imh-python/lib/python3.9/site-packages/Crypto/Cipher/_mode_ofb.py (10281B)

# -*- coding: utf-8 -*-
#
#  Cipher/mode_ofb.py : OFB mode
#
# ===================================================================
# 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.
# ===================================================================

"""
Output Feedback (CFB) mode.
"""

__all__ = ['OfbMode']

from Crypto.Util.py3compat import _copy_bytes
from Crypto.Util._raw_api import (load_pycryptodome_raw_lib, VoidPointer,
                                  create_string_buffer, get_raw_buffer,
                                  SmartPointer, c_size_t, c_uint8_ptr,
                                  is_writeable_buffer)

from Crypto.Random import get_random_bytes

raw_ofb_lib = load_pycryptodome_raw_lib("Crypto.Cipher._raw_ofb", """
                        int OFB_start_operation(void *cipher,
                                                const uint8_t iv[],
                                                size_t iv_len,
                                                void **pResult);
                        int OFB_encrypt(void *ofbState,
                                        const uint8_t *in,
                                        uint8_t *out,
                                        size_t data_len);
                        int OFB_decrypt(void *ofbState,
                                        const uint8_t *in,
                                        uint8_t *out,
                                        size_t data_len);
                        int OFB_stop_operation(void *state);
                        """
                                        )

class OfbMode(object):
    """*Output FeedBack (OFB)*.

This mode is very similar to CBC, but it
    transforms the underlying block cipher into a stream cipher.

The keystream is the iterated block encryption of the
    previous ciphertext block.

An Initialization Vector (*IV*) is required.

See `NIST SP800-38A`_ , Section 6.4.

.. _`NIST SP800-38A` : http://csrc.nist.gov/publications/nistpubs/800-38a/sp800-38a.pdf

:undocumented: __init__
    """

def __init__(self, block_cipher, iv):
        """Create a new block cipher, configured in OFB mode.

:Parameters:
          block_cipher : C pointer
            A smart pointer to the low-level block cipher instance.

iv : bytes/bytearray/memoryview
            The initialization vector to use for encryption or decryption.
            It is as long as the cipher block.

**The IV must be a nonce, to to be reused for any other
            message**. It shall be a nonce or a random value.

Reusing the *IV* for encryptions performed with the same key
            compromises confidentiality.
        """

self._state = VoidPointer()
        result = raw_ofb_lib.OFB_start_operation(block_cipher.get(),
                                                 c_uint8_ptr(iv),
                                                 c_size_t(len(iv)),
                                                 self._state.address_of())
        if result:
            raise ValueError("Error %d while instantiating the OFB mode"
                             % result)

# Ensure that object disposal of this Python object will (eventually)
        # free the memory allocated by the raw library for the cipher mode
        self._state = SmartPointer(self._state.get(),
                                   raw_ofb_lib.OFB_stop_operation)

# Memory allocated for the underlying block cipher is now owed
        # by the cipher mode
        block_cipher.release()

self.block_size = len(iv)
        """The block size of the underlying cipher, in bytes."""

self.iv = _copy_bytes(None, None, iv)
        """The Initialization Vector originally used to create the object.
        The value does not change."""

self.IV = self.iv
        """Alias for `iv`"""

self._next = [ self.encrypt, self.decrypt ]

def encrypt(self, plaintext, output=None):
        """Encrypt data with the key and the parameters set at initialization.

A cipher object is stateful: once you have encrypted a message
        you cannot encrypt (or decrypt) another message using the same
        object.

The data to encrypt can be broken up in two or
        more pieces and `encrypt` can be called multiple times.

That is, the statement:

>>> c.encrypt(a) + c.encrypt(b)

is equivalent to:

>>> c.encrypt(a+b)

This function does not add any padding to the plaintext.

:Parameters:
          plaintext : bytes/bytearray/memoryview
            The piece of data to encrypt.
            It can be of any length.
        :Keywords:
          output : bytearray/memoryview
            The location where the ciphertext must be written to.
            If ``None``, the ciphertext is returned.
        :Return:
          If ``output`` is ``None``, the ciphertext is returned as ``bytes``.
          Otherwise, ``None``.
        """

if self.encrypt not in self._next:
            raise TypeError("encrypt() cannot be called after decrypt()")
        self._next = [ self.encrypt ]
        
        if output is None:
            ciphertext = create_string_buffer(len(plaintext))
        else:
            ciphertext = output
            
            if not is_writeable_buffer(output):
                raise TypeError("output must be a bytearray or a writeable memoryview")
        
            if len(plaintext) != len(output):
                raise ValueError("output must have the same length as the input"
                                 "  (%d bytes)" % len(plaintext))

result = raw_ofb_lib.OFB_encrypt(self._state.get(),
                                         c_uint8_ptr(plaintext),
                                         c_uint8_ptr(ciphertext),
                                         c_size_t(len(plaintext)))
        if result:
            raise ValueError("Error %d while encrypting in OFB mode" % result)

if output is None:
            return get_raw_buffer(ciphertext)
        else:
            return None

def decrypt(self, ciphertext, output=None):
        """Decrypt data with the key and the parameters set at initialization.

A cipher object is stateful: once you have decrypted a message
        you cannot decrypt (or encrypt) another message with the same
        object.

The data to decrypt can be broken up in two or
        more pieces and `decrypt` can be called multiple times.

That is, the statement:

>>> c.decrypt(a) + c.decrypt(b)

is equivalent to:

>>> c.decrypt(a+b)

This function does not remove any padding from the plaintext.

:Parameters:
          ciphertext : bytes/bytearray/memoryview
            The piece of data to decrypt.
            It can be of any length.
        :Keywords:
          output : bytearray/memoryview
            The location where the plaintext is written to.
            If ``None``, the plaintext is returned.
        :Return:
          If ``output`` is ``None``, the plaintext is returned as ``bytes``.
          Otherwise, ``None``.
        """

if self.decrypt not in self._next:
            raise TypeError("decrypt() cannot be called after encrypt()")
        self._next = [ self.decrypt ]
        
        if output is None:
            plaintext = create_string_buffer(len(ciphertext))
        else:
            plaintext = output

if not is_writeable_buffer(output):
                raise TypeError("output must be a bytearray or a writeable memoryview")
            
            if len(ciphertext) != len(output):
                raise ValueError("output must have the same length as the input"
                                 "  (%d bytes)" % len(plaintext))

result = raw_ofb_lib.OFB_decrypt(self._state.get(),
                                         c_uint8_ptr(ciphertext),
                                         c_uint8_ptr(plaintext),
                                         c_size_t(len(ciphertext)))
        if result:
            raise ValueError("Error %d while decrypting in OFB mode" % result)

if output is None:
            return get_raw_buffer(plaintext)
        else:
            return None

def _create_ofb_cipher(factory, **kwargs):
    """Instantiate a cipher object that performs OFB encryption/decryption.

:Parameters:
      factory : module
        The underlying block cipher, a module from ``Crypto.Cipher``.

:Keywords:
      iv : bytes/bytearray/memoryview
        The IV to use for OFB.

IV : bytes/bytearray/memoryview
        Alias for ``iv``.

Any other keyword will be passed to the underlying block cipher.
    See the relevant documentation for details (at least ``key`` will need
    to be present).
    """

cipher_state = factory._create_base_cipher(kwargs)
    iv = kwargs.pop("IV", None)
    IV = kwargs.pop("iv", None)

if (None, None) == (iv, IV):
        iv = get_random_bytes(factory.block_size)
    if iv is not None:
        if IV is not None:
            raise TypeError("You must either use 'iv' or 'IV', not both")
    else:
        iv = IV

if len(iv) != factory.block_size:
        raise ValueError("Incorrect IV length (it must be %d bytes long)" %
                factory.block_size)

if kwargs:
        raise TypeError("Unknown parameters for OFB: %s" % str(kwargs))

return OfbMode(cipher_state, iv)

cmd: