pythonpython-3.xntlmhashlibntlm-authentication

MD4 hashlib support in Python 3.8


I am trying to implement a soap client for a server that uses NTLM authentication. The libraries that I use (requests-ntlm2 which relies on ntlm-auth) implement the MD4 algorithm that lies in the core of the NTLM protocol via the standard library's hashlib.

Although hashlib seems to support MD4:

>>> import hashlib
>>> hashlib.algorithms_available
{'md5-sha1', 'md4', 'shake_128', 'md5', 'blake2s', 'sha3_512', 'ripemd160', 'sha512', 'mdc2', 'blake2b', 'sha3_256', 'sha3_224', 'sha512_224', 'sha1', 'sha384', 'sha256', 'sha224', 'whirlpool', 'sha512_256', 'sha3_384', 'shake_256', 'sm3'}
>>>

and so does the openssl library in my system:

(victory) C:\code\python\services>openssl
help:
[...]
Message Digest commands (see the `dgst' command for more details)
blake2b512        blake2s256        md4               md5
mdc2              rmd160            sha1              sha224
sha256            sha3-224          sha3-256          sha3-384
sha3-512          sha384            sha512            sha512-224
sha512-256        shake128          shake256          sm3
[...]

when the authentication tries to run python produces an ValueError: unsupported hash type md4 error. Here is the relevant part of the traceback:

C:\ProgramData\Miniconda3\envs\victory\lib\site-packages\ntlm_auth\compute_hash.py in _ntowfv1(password)
    165         return nt_hash
    166 
--> 167     digest = hashlib.new('md4', password.encode('utf-16-le')).digest()
    168 
    169     return digest

C:\ProgramData\Miniconda3\envs\victory\lib\hashlib.py in __hash_new(name, data, **kwargs)
    161         # This allows for SHA224/256 and SHA384/512 support even though
    162         # the OpenSSL library prior to 0.9.8 doesn't provide them.
--> 163         return __get_builtin_constructor(name)(data)
    164 
    165 

C:\ProgramData\Miniconda3\envs\victory\lib\hashlib.py in __get_builtin_constructor(name)
    118         return constructor
    119 
--> 120     raise ValueError('unsupported hash type ' + name)
    121 
    122 

ValueError: unsupported hash type md4

Even when I try to merely call the MD4 from hashlib, I get the same result:

>>> import hashlib
>>> hashlib.new('md4')
Traceback (most recent call last):
  File "C:\ProgramData\Miniconda3\envs\victory\lib\hashlib.py", line 157, in __hash_new
    return _hashlib.new(name, data)
ValueError: [digital envelope routines] initialization error

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "C:\ProgramData\Miniconda3\envs\victory\lib\hashlib.py", line 163, in __hash_new
    return __get_builtin_constructor(name)(data)
  File "C:\ProgramData\Miniconda3\envs\victory\lib\hashlib.py", line 120, in __get_builtin_constructor
    raise ValueError('unsupported hash type ' + name)
ValueError: unsupported hash type md4

Any insights about what's going on and/or any help would be immensely appreciated.


Solution

  • Well, it seems that there was something corrupted in my conda environment. I created a new identical one, and it's been working ever since without having to change anything else.