FM / Cipher

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

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

Name	Size	Mode	Actions
__pycache__/	-	0755	rm
AES.py	9569	0644	edit dl rm
AES.pyi	1387	0644	edit dl rm
ARC2.py	7026	0644	edit dl rm
ARC2.pyi	982	0644	edit dl rm
ARC4.py	5168	0644	edit dl rm
ARC4.pyi	431	0644	edit dl rm
Blowfish.py	5976	0644	edit dl rm
Blowfish.pyi	1018	0644	edit dl rm
CAST.py	6087	0644	edit dl rm
CAST.pyi	983	0644	edit dl rm
ChaCha20.py	10754	0644	edit dl rm
ChaCha20.pyi	762	0644	edit dl rm
ChaCha20_Poly1305.py	11561	0644	edit dl rm
ChaCha20_Poly1305.pyi	1068	0644	edit dl rm
DES.py	5963	0644	edit dl rm
DES.pyi	963	0644	edit dl rm
DES3.py	6941	0644	edit dl rm
DES3.pyi	1033	0644	edit dl rm
PKCS1_OAEP.py	8880	0644	edit dl rm
PKCS1_OAEP.pyi	1183	0644	edit dl rm
PKCS1_v1_5.py	7979	0644	edit dl rm
PKCS1_v1_5.pyi	571	0644	edit dl rm
Salsa20.py	6369	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	5217	0644	edit dl rm
_EKSBlowfish.pyi	270	0644	edit dl rm
_mode_cbc.py	10971	0644	edit dl rm
_mode_cbc.pyi	691	0644	edit dl rm
_mode_ccm.py	24476	0644	edit dl rm
_mode_ccm.pyi	1600	0644	edit dl rm
_mode_cfb.py	10821	0644	edit dl rm
_mode_cfb.pyi	731	0644	edit dl rm
_mode_ctr.py	15920	0644	edit dl rm
_mode_ctr.pyi	804	0644	edit dl rm
_mode_eax.py	14543	0644	edit dl rm
_mode_eax.pyi	1545	0644	edit dl rm
_mode_ecb.py	8222	0644	edit dl rm
_mode_ecb.pyi	596	0644	edit dl rm
_mode_gcm.py	21402	0644	edit dl rm
_mode_gcm.pyi	1541	0644	edit dl rm
_mode_ocb.py	19838	0644	edit dl rm
_mode_ocb.pyi	1231	0644	edit dl rm
_mode_ofb.py	10301	0644	edit dl rm
_mode_ofb.pyi	695	0644	edit dl rm
_mode_openpgp.py	7061	0644	edit dl rm
_mode_openpgp.pyi	556	0644	edit dl rm
_mode_siv.py	14094	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	2888	0644	edit dl rm
__init__.pyi	0	0644	edit dl rm

Edit: /opt/imh-python/lib/python3.9/site-packages/Cryptodome/Cipher/PKCS1_OAEP.py (8880B)

# -*- coding: utf-8 -*-
#
#  Cipher/PKCS1_OAEP.py : PKCS#1 OAEP
#
# ===================================================================
# 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.Signature.pss import MGF1
import Cryptodome.Hash.SHA1

from Cryptodome.Util.py3compat import bord, _copy_bytes
import Cryptodome.Util.number
from   Cryptodome.Util.number import ceil_div, bytes_to_long, long_to_bytes
from   Cryptodome.Util.strxor import strxor
from Cryptodome import Random

class PKCS1OAEP_Cipher:
    """Cipher object for PKCS#1 v1.5 OAEP.
    Do not create directly: use :func:`new` instead."""

def __init__(self, key, hashAlgo, mgfunc, label, randfunc):
        """Initialize this PKCS#1 OAEP cipher object.

:Parameters:
         key : an RSA key object
                If a private half is given, both encryption and decryption are possible.
                If a public half is given, only encryption is possible.
         hashAlgo : hash object
                The hash function to use. This can be a module under `Cryptodome.Hash`
                or an existing hash object created from any of such modules. If not specified,
                `Cryptodome.Hash.SHA1` is used.
         mgfunc : callable
                A mask generation function that accepts two parameters: a string to
                use as seed, and the lenth of the mask to generate, in bytes.
                If not specified, the standard MGF1 consistent with ``hashAlgo`` is used (a safe choice).
         label : bytes/bytearray/memoryview
                A label to apply to this particular encryption. If not specified,
                an empty string is used. Specifying a label does not improve
                security.
         randfunc : callable
                A function that returns random bytes.

:attention: Modify the mask generation function only if you know what you are doing.
                    Sender and receiver must use the same one.
        """
        self._key = key

if hashAlgo:
            self._hashObj = hashAlgo
        else:
            self._hashObj = Cryptodome.Hash.SHA1

if mgfunc:
            self._mgf = mgfunc
        else:
            self._mgf = lambda x,y: MGF1(x,y,self._hashObj)

self._label = _copy_bytes(None, None, label)
        self._randfunc = randfunc

def can_encrypt(self):
        """Legacy function to check if you can call :meth:`encrypt`.

.. deprecated:: 3.0"""
        return self._key.can_encrypt()

def can_decrypt(self):
        """Legacy function to check if you can call :meth:`decrypt`.

.. deprecated:: 3.0"""
        return self._key.can_decrypt()

def encrypt(self, message):
        """Encrypt a message with PKCS#1 OAEP.

:param message:
            The message to encrypt, also known as plaintext. It can be of
            variable length, but not longer than the RSA modulus (in bytes)
            minus 2, minus twice the hash output size.
            For instance, if you use RSA 2048 and SHA-256, the longest message
            you can encrypt is 190 byte long.
        :type message: bytes/bytearray/memoryview

:returns: The ciphertext, as large as the RSA modulus.
        :rtype: bytes

:raises ValueError:
            if the message is too long.
        """

# See 7.1.1 in RFC3447
        modBits = Cryptodome.Util.number.size(self._key.n)
        k = ceil_div(modBits, 8) # Convert from bits to bytes
        hLen = self._hashObj.digest_size
        mLen = len(message)

# Step 1b
        ps_len = k - mLen - 2 * hLen - 2
        if ps_len < 0:
            raise ValueError("Plaintext is too long.")
        # Step 2a
        lHash = self._hashObj.new(self._label).digest()
        # Step 2b
        ps = b'\x00' * ps_len
        # Step 2c
        db = lHash + ps + b'\x01' + _copy_bytes(None, None, message)
        # Step 2d
        ros = self._randfunc(hLen)
        # Step 2e
        dbMask = self._mgf(ros, k-hLen-1)
        # Step 2f
        maskedDB = strxor(db, dbMask)
        # Step 2g
        seedMask = self._mgf(maskedDB, hLen)
        # Step 2h
        maskedSeed = strxor(ros, seedMask)
        # Step 2i
        em = b'\x00' + maskedSeed + maskedDB
        # Step 3a (OS2IP)
        em_int = bytes_to_long(em)
        # Step 3b (RSAEP)
        m_int = self._key._encrypt(em_int)
        # Step 3c (I2OSP)
        c = long_to_bytes(m_int, k)
        return c

def decrypt(self, ciphertext):
        """Decrypt a message with PKCS#1 OAEP.

:param ciphertext: The encrypted message.
        :type ciphertext: bytes/bytearray/memoryview

:returns: The original message (plaintext).
        :rtype: bytes

:raises ValueError:
            if the ciphertext has the wrong length, or if decryption
            fails the integrity check (in which case, the decryption
            key is probably wrong).
        :raises TypeError:
            if the RSA key has no private half (i.e. you are trying
            to decrypt using a public key).
        """

# See 7.1.2 in RFC3447
        modBits = Cryptodome.Util.number.size(self._key.n)
        k = ceil_div(modBits,8) # Convert from bits to bytes
        hLen = self._hashObj.digest_size

# Step 1b and 1c
        if len(ciphertext) != k or k<hLen+2:
            raise ValueError("Ciphertext with incorrect length.")
        # Step 2a (O2SIP)
        ct_int = bytes_to_long(ciphertext)
        # Step 2b (RSADP)
        m_int = self._key._decrypt(ct_int)
        # Complete step 2c (I2OSP)
        em = long_to_bytes(m_int, k)
        # Step 3a
        lHash = self._hashObj.new(self._label).digest()
        # Step 3b
        y = em[0]
        # y must be 0, but we MUST NOT check it here in order not to
        # allow attacks like Manger's (http://dl.acm.org/citation.cfm?id=704143)
        maskedSeed = em[1:hLen+1]
        maskedDB = em[hLen+1:]
        # Step 3c
        seedMask = self._mgf(maskedDB, hLen)
        # Step 3d
        seed = strxor(maskedSeed, seedMask)
        # Step 3e
        dbMask = self._mgf(seed, k-hLen-1)
        # Step 3f
        db = strxor(maskedDB, dbMask)
        # Step 3g
        one_pos = db[hLen:].find(b'\x01')
        lHash1 = db[:hLen]
        invalid = bord(y) | int(one_pos < 0)
        hash_compare = strxor(lHash1, lHash)
        for x in hash_compare:
            invalid |= bord(x)
        for x in db[hLen:one_pos]:
            invalid |= bord(x)
        if invalid != 0:
            raise ValueError("Incorrect decryption.")
        # Step 4
        return db[hLen + one_pos + 1:]

def new(key, hashAlgo=None, mgfunc=None, label=b'', randfunc=None):
    """Return a cipher object :class:`PKCS1OAEP_Cipher` that can be used to perform PKCS#1 OAEP encryption or decryption.

:param key:
      The key object to use to encrypt or decrypt the message.
      Decryption is only possible with a private RSA key.
    :type key: RSA key object

:param hashAlgo:
      The hash function to use. This can be a module under `Cryptodome.Hash`
      or an existing hash object created from any of such modules.
      If not specified, `Cryptodome.Hash.SHA1` is used.
    :type hashAlgo: hash object

:param mgfunc:
      A mask generation function that accepts two parameters: a string to
      use as seed, and the lenth of the mask to generate, in bytes.
      If not specified, the standard MGF1 consistent with ``hashAlgo`` is used (a safe choice).
    :type mgfunc: callable

:param label:
      A label to apply to this particular encryption. If not specified,
      an empty string is used. Specifying a label does not improve
      security.
    :type label: bytes/bytearray/memoryview

:param randfunc:
      A function that returns random bytes.
      The default is `Random.get_random_bytes`.
    :type randfunc: callable
    """

if randfunc is None:
        randfunc = Random.get_random_bytes
    return PKCS1OAEP_Cipher(key, hashAlgo, mgfunc, label, randfunc)

cmd: