Assistance with WinSCP and PGP public key

I've read that WinSCP does encrypt with PGP, but can it still work in the following situation?
Vendor Requirements:
I have been asked to complete the following requirements:

1. Client supplies public SSH key.
   
   1. Keys must be RSA format (2048-4096 bit, 2048 recommended).
      
   
   
2. If client is planning on extracting information out of Concur we will also need a public PGP key.
   
   1. PGP public key must be formatted as OpenPGP (version 4)
      
   2. ASCII-armored keys are supported
      
   3. You will need to have a public signing key, and an encryption sub-key (this is the default generated by GnuPG, for example)
      
   4. Keys should be either DSS/ElGamal (1024-3072 bit, 2048 recommended) or RSA type 1 (sign and encrypt, 1024-4096 bit, 2048 recommended)
      
   5. Set key to never expire
      

My requirements:
Ultimately, I need to automate the following process: access their SFTP server, extract the file, and download it to a local file where I will run other automation on it.

WinSCP does not support PGP. Where did you read that?

I'm new to this SFTP and PGP thing. In my research, I found this other post on WinSCP about it: Signing with PGP via WinSCP.com.

I tried to provide all the details and requirements in my original post. Sorry if I'm not clear or perhaps I do not understand the requirements myself. Please let me know if you have any other questions.

kcbocca wrote:

I'm new to this SFTP and PGP thing. In my research, I found this other post on WinSCP about it: Signing with PGP via WinSCP.com.

My answer there is: "WinSCP cannot sign file with PGP."

Hi, we have a use case where there's an existing SFTP implementation based around a Linux SFTP server and using PGP to encrypt/decrypt files at rest.

I would like to transfer files to and from this SFTP server where the file is automatically encrypted on transfer TO the SFTP server and decrypted on transfer FROM the SFTP server, just the same way it works with WinSCP and AES out of the box. We really like WinSCP and are trying not to implement another SFTP program that supports PGP.

Does anyone know if this would be feasible using the .NET assembly and PowerShell to run the appropriate OpenPGP commands in the background, so that the user experience would be transparent – similar to using the inbuilt AES encryption functionality.

Thanks in advance

@talloaks: If you implement the transfer in PowerShell (and WinSCP .NET assembly), there's of course nothing preventing you encrypting the files using PGP before the transfer.