Hostkey being modified during automation with subprocess.popen in Python
Hello WinSCP Community,
as part of a larger task I want to move some files, work on them and return the new files to the SFTP server. Due to restrictions laid upon me I am only able to use Python 3.4, which excludes me from any nice and fancy modules like Paramiko and pysftp.
Connection to the server fails, according to the stdout pipe the hostkey is incorrect. The returned "incorrect" key is not identical to the one that was passed to the function. It has an additional, leading backslash and is cut short. The originally passed key is
The presumption is, that
Things I have tried:
I would greatly appreciate any help. The alternative would be to write and call shell scripts, but that would be cumbersome and awkward to implement in the larger code.
Thank you for your time.
as part of a larger task I want to move some files, work on them and return the new files to the SFTP server. Due to restrictions laid upon me I am only able to use Python 3.4, which excludes me from any nice and fancy modules like Paramiko and pysftp.
Connection to the server fails, according to the stdout pipe the hostkey is incorrect. The returned "incorrect" key is not identical to the one that was passed to the function. It has an additional, leading backslash and is cut short. The originally passed key is
"ssh-XXXXXXX 256 XXXXXXX". The "incorrect" key is "\ssh-XXXXXXX"
The presumption is, that
subprocess.Popen mangles the string in a way.
- hostkey, passphrase, and privatekey are all necessary
- the hostkey has been generated directly by the server and matches the fingerprint returned by the stdout pipe
- the connection works when done in a Windows shell, but implementation in Python is desired.
- the connection works when accepting any given Key through usage of
*, but that would obviously be insecure, therefore not viable.
array_to_be_joined = ['path/WinSCP.com', '/ini=nul', '/command', 'open sftp://sessionURL/ -hostkey="{}" -passphrase={} -privatekey=path/privatekey.ppk'.format(hostkey,passphrase), 'echo helloWorld'] process = subprocess.Popen( array_to_be_joined, stdin=subprocess.PIPE,stdout=subprocess.PIPE, stderr=subprocess.PIPE)
- wrote the parameters in the
subprocess.Popenfunction
- wrote the parameters into a list and passed the list to the function
- passed the hostkey in a variable through
string.format
- passed the hostkey in plaintext
- tried the hostkey in:
- single quotes
- single quotes escaped with
\
- single quotes escaped with
`
- two single quotes
- two single quotes escaped with
\
- two single quotes escaped with
`
- double quotes
- double quotes escaped with
\
- double quotes escaped with
`
- two double quotes
- two double quotes escaped with
\
- two double quotes escaped with
`
- without quotes
- single quotes
Looking for remote computer... Connecting to remote computer... Authenticating... Hostkey does not match konfigured key "\ssh-XXXXXXX"! Server Key-Fingerprint is ssh-XXXXXXX 256 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX Sign-up failed.
Thank you for your time.
- Output.png (7.49 KB)
