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Using Fernet

For a multi-language encrypted data format...
  See info/crypto/fernet_encryption.txt

Requires extra installation
  pip install cryptography
Also installs cffi and pycparser (which is not needed!)

This seemed to be designed for small data encryptions!
and is perfect for encrypted messages between say a PHP front end and python
backend (via redis message queues)

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PyCrypto

Requires extra installation (older legacy install)
  pip3 install pycrypto

This installs module named "Crypto"
It also requires compilation on Windows

AES encryption of files in Python with PyCrypto
  https://eli.thegreenplace.net/2010/06/25/aes-encryption-of-files-in-python-with-pycrypto/

Basic Raw (over simplistic) Example...
https://stackoverflow.com/questions/16761458/
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from Crypto.Cipher import AES

cypher = AES.new('This is a key123', AES.MODE_CBC, 'This is an IV456')
message = "The answer is no"
ciphertext = cypher.encrypt(message)
ciphertext
# => b'\xd6\x83\x8dd!VT\x92\xaa`A\x05\xe0\x9b\x8b\xf1'

cypher = AES.new('This is a key123', AES.MODE_CBC, 'This is an IV456')
cypher.decrypt(ciphertext)
# => b'The answer is no'
#
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Decrypting OpenSSL encrypted text...

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import base64
import hashlib
from Crypto.Cipher import AES       #requires pycrypto

# decoding the result of...
#  echo -n 'Hello World!' | openssl aes-256-cbc -e -a -salt -pbkdf2 -iter 10000
#

openssloutputb64='U2FsdGVkX1/Kf8Yo6JjBh+qELWhirAXr78+bbPQjlxE='
password='p4$$w0rd'
pbkdf2iterations=100000

# convert inputs to bytes
openssloutputbytes = base64.b64decode(openssloutputb64)
passwordbytes = password.encode('utf-8')

# salt is bytes 8 through 15 of openssloutputbytes
salt = openssloutputbytes[8:16]

# derive a 48-byte key using pbkdf2 given the password and salt
# with 10,000 iterations of sha256 hashing
derivedkey = hashlib.pbkdf2_hmac(
      'sha256', passwordbytes, salt, pbkdf2iterations, 48 )

# key is bytes 0-31 of derivedkey, iv is bytes 32-47 of derivedkey
key = derivedkey[0:32]
iv = derivedkey[32:48]

# ciphertext is bytes 16-end of openssloutputbytes
ciphertext = openssloutputbytes[16:]

# decrypt ciphertext using aes-cbc, given key, iv, and ciphertext
decryptor = AES.new(key, AES.MODE_CBC, iv)
plaintext = decryptor.decrypt(ciphertext)

# Remove PKCS#7 padding.
# Last byte of plaintext indicates the number of padding bytes appended
# to end.  This is the number of bytes to be removed.
plaintext = plaintext[:-plaintext[-1]]

# output results
print('openssloutputb64:', openssloutputb64)
print('password:', password)
print('salt:', salt.hex())
print('key: ', key.hex())
print('iv: ', iv.hex())
print('ciphertext: ', ciphertext.hex())
print('plaintext: ', plaintext.decode('utf-8'))

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Results...

openssloutputb64: U2FsdGVkX1/Kf8Yo6JjBh+qELWhirAXr78+bbPQjlxE=
password: p4$$w0rd
salt: ca7fc628e898c187
key:  444ab886d5721fc87e58f86f3e7734659007bea7fbe790541d9e73c481d9d983
iv:  7f4597a18096715d7f9830f0125be8fd
ciphertext:  ea842d6862ac05ebefcf9b6cf4239711
plaintext:  Hello World!

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SimplyCrypt

  https://github.com/andrewcooke/simple-crypt
  https://pypi.org/project/simple-crypt/

Uses  PyCrypto with a AES256 cypher

Extra Installation
  pip install simple-crypt

Password is hashed using PBKDF2 with SHA256, a 256 bit random salt

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from simplecrypt import encrypt, decrypt

f = open('file.csv','r').read()
ciphertext = encrypt('USERPASSWORD',f.encode('utf8'))

e = open('file.enc','wb')
e.write(ciphertext)

e.close

# return to a utf8 string
# plaintext = decrypt('password', ciphertext).decode('utf8')

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Hashing

  import hashlib
  data="abc"

  hashlib.algorithms_available

  # sha256 hexadecimal
  hash = hashlib.sha256(data.encode()).hexdigest()
  # => 'ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad'

  # sha256 base64
  import base64
  hash = hashlib.sha256(data.encode()).digest()  # as a byte string
  hash_b64 = base64.b64encode(hash).decode()     # decode to utf-8
  # => 'ungWv48Bz+pBQUDeXa4iI7ADYaOWF3qctBD/YfIAFa0='

  # sha1 hexadecimal
  hash hashlib.sha1(data.encode()).hexdigest()
  # => 'a9993e364706816aba3e25717850c26c9cd0d89d'

  # md5 hexadecimal
  hash = hashlib.md5(data.encode()).hexdigest()
  # => '900150983cd24fb0d6963f7d28e17f72'

  # openssl 'ripemd160'
  h = hashlib.new('ripemd160')
  h.update(data.encode())
  hash = h.hexdigest()

Key Derivation

NOTE: this is about 3 times slower than "openssl" pbkdf2_hmac()
for the same result

  key = hashlib.pbkdf2_hmac('sha256', b'password', b'salt', 100000)
  binascii.hexlify(key)

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