[Cryptography-dev] Python cryptography fails to load due to _rust DDL import error

[Alex Gaynor]

Not particularly.

Based on the error message you shared, when Python attempted to import
_rust.dll, it encountered the error "The specified module could not be
found." I'm inferring that this means that something about the module
could not be loaded. Perhaps _rust.dll is linked dynamically against
another library that's not on the load path?

Are you building cryptography from source, or installing from a pre-built wheel?

Alex

On Fri, Aug 4, 2023 at 12:23 PM Gualtiero Scotti <tierox at gmail.com> wrote:
>
> Thank you Alex for your response.  Could you provide me more details? Thanks in advance
>
> Il Ven 4 Ago 2023, 18:02 Alex Gaynor <alex.gaynor at gmail.com> ha scritto:
>>
>> This very likely indicates that however you've packaged and installed
>> the application in your environment isn't properly including the
>> extension module for cryptography.
>>
>> Alex
>>
>> On Fri, Aug 4, 2023 at 11:20 AM Gualtiero Scotti <tierox at gmail.com> wrote:
>> >
>> > I'm struggling with this issue from few days...
>> >
>> > I've a Python application that can run in two ways:
>> >
>> > Stand alone -> launched directly using the python interpreter
>> > From a windows service -> wrapping application with pywin32 and using the same interpreter
>> >
>> > When app starts in standalone mode it works fine but when starts through Windows service it fails with the following stackTrace:
>> >
>> > .............................
>> > from cryptography.hazmat.primitives.kdf.pbkdf2 import PBKDF2HMAC
>> > File "C:\Program Files (x86)\...\Python\Lib\site-package\cryptography\hazmat\primitives\kdf\pbkdf2.py", line 10, in <module>
>> > from cryptography.exceptions import (
>> > File "C:\Program Files (x86)\...\Python\Lib\site-packages\cryptography\exceptions.py", line 9, in <module>
>> > from cryptography.hazmat.bindings._rust import exceptions as rust_exceptions
>> > ImportError: DLL load failed while importing _rust: The specified module could not be found."
>> >
>> > I' don't know wich DLLs cryptography uses.....maybe they are not in librarypath???
>> >
>> > Python 3.11.3 32-bit
>> > Windows 11
>> >
>> > Requirements.txt
>> >
>> > pywin32==305 pywin32-ctypes~=0.2.0 Flask~=2.1.2 flask-login~=0.6.1 Werkzeug~=2.0.2 waitress~=2.1.2 websockets~=10.3 transitions~=0.8.11 bitstruct~=8.15.1 PyYAML~=6.0 passlib~=1.7.4 dacite~=1.5.1 paho-mqtt~=1.6.1 setuptools~=60.2.0 six~=1.16.0 MarkupSafe~=2.1.1 click~=8.1.3 itsdangerous~=2.1.2 Jinja2~=3.1.2 pythonnet~=3.0.1 requests~=2.29.0 pyserial~=3.5.0 zeep~=4.2.1 cryptography~=41.0.2 pycryptodome~=3.18.0
>> >
>> > Did someone have the same issue? Any suggestion is appreciated.
>> >
>> > Thanks in advance.
>> >
>> > _______________________________________________
>> > Cryptography-dev mailing list
>> > Cryptography-dev at python.org
>> > https://mail.python.org/mailman/listinfo/cryptography-dev
>>
>>
>>
>> --
>> All that is necessary for evil to succeed is for good people to do nothing.
>> _______________________________________________
>> Cryptography-dev mailing list
>> Cryptography-dev at python.org
>> https://mail.python.org/mailman/listinfo/cryptography-dev
>
> _______________________________________________
> Cryptography-dev mailing list
> Cryptography-dev at python.org
> https://mail.python.org/mailman/listinfo/cryptography-dev



-- 
All that is necessary for evil to succeed is for good people to do nothing.