EVP_BytesToKey implementation in other languages: Python, Node.js

EVP_BytesToKey implementation in other languages

https://crypto.stackexchange.com/questions/3298/is-there-a-standard-for-openssl-interoperable-aes-encryption/35614#35614

https://security.stackexchange.com/questions/29106/openssl-recover-key-and-iv-by-passphrase

Following code steal from [Simple python functions that provide openssl -aes-256-cbc compatible encrypt/decrypt] (http://joelinoff.com/blog/?p=885)

# ================================================================
# get_key_and_iv
# ================================================================
def get_key_and_iv(password, salt, klen=32, ilen=16, msgdgst='md5'):
    '''
    Derive the key and the IV from the given password and salt.

    This is a niftier implementation than my direct transliteration of
    the C++ code although I modified to support different digests.

    CITATION: http://stackoverflow.com/questions/13907841/implement-openssl-aes-encryption-in-python

    @param password  The password to use as the seed.
    @param salt      The salt.
    @param klen      The key length.
    @param ilen      The initialization vector length.
    @param msgdgst   The message digest algorithm to use.
    '''
    # equivalent to:
    #   from hashlib import <mdi> as mdf
    #   from hashlib import md5 as mdf
    #   from hashlib import sha512 as mdf
    mdf = getattr(__import__('hashlib', fromlist=[msgdgst]), msgdgst)
    password = password.encode('ascii', 'ignore')  # convert to ASCII

    try:
        maxlen = klen + ilen
        keyiv = mdf(password + salt).digest()
        tmp = [keyiv]
        while len(tmp) < maxlen:
            tmp.append( mdf(tmp[-1] + password + salt).digest() )
            keyiv += tmp[-1]  # append the last byte
        key = keyiv[:klen]
        iv = keyiv[klen:klen+ilen]
        return key, iv
    except UnicodeDecodeError:
        return None, None

The decent implementation from the discussion.

import hashlib, binascii
from passlib.utils.pbkdf2 import pbkdf1

def hasher(algo, data):
    hashes = {'md5': hashlib.md5, 'sha256': hashlib.sha256,
    'sha512': hashlib.sha512}
    h = hashes[algo]()
    h.update(data)

    return h.digest()

# pwd and salt must be bytes objects
def openssl_kdf(algo, pwd, salt, key_size, iv_size):
    if algo == 'md5':
        temp = pbkdf1(pwd, salt, 1, 16, 'md5')
    else:
        temp = b''

    fd = temp    
    while len(fd) < key_size + iv_size:
        temp = hasher(algo, temp + pwd + salt)
        fd += temp

    key = fd[0:key_size]
    iv = fd[key_size:key_size+iv_size]

    print('salt=' + binascii.hexlify(salt).decode('ascii').upper())
    print('key=' + binascii.hexlify(key).decode('ascii').upper())
    print('iv=' + binascii.hexlify(iv).decode('ascii').upper())

    return key, iv

openssl_kdf('md5', b'test', b'\xF6\x81\x8C\xAE\x13\x18\x72\xBD', 32, 16)

generates the same output as:

openssl enc -aes-256-cbc -P -pass pass:test -S F6818CAE131872BD

openssl_kdf('sha256', b'test', b'\xF6\x81\x8C\xAE\x13\x18\x72\xBD', 32, 16)

generates the same output as:

openssl enc -aes-256-cbc -P -pass pass:test -S F6818CAE131872BD -md SHA256

A nodes.js implementation with MD5 only https://github.com/crypto-browserify/EVP_BytesToKey/blob/master/index.js