SFTP (prebuilt connector)

Description

The Patchworks SFTP connector is used to connect SFTP servers, for use in process flows.

Authentication

When adding connector instances for the Patchworks SFTP connector, the following authentication methods are supported:

• SFTP User Pass (username & password)

• SFTP Key Pass (private & public key files)

Guidance for using these authentication methods is summarised below.

User pass

The Patchworks SFTP connector supports authentication via username/password. If you choose to add a connector instance with user pass authentication, you need to enter the following details:

Key pass

The Patchworks SFTP connector supports authentication via public/private keys. If you choose to add a connector instance with key pass authentication, you need to enter the following details:

Generating host fingerprint values

Server finger prints are created using the FTP server’s public key. The server will provide this in either SSH-RSA or SSH-SHA format. Patchworks chooses the most secure public key format available on the FTP server for fingerprint verification, noting that:

• The public key must be Base64 decoded and then hashed with either md5 or sha512 algorithms.

• The preferred key format is ssh-ed25519 but ssh-rsa format is acceptable.

The steps below summarise how to generate a host server fingerprint:

Step 1 Assuming that your public key is stored on your FTP server, you can use the following OpenSSH command to scan the available public key and save it to a local file:

ssh-keyscan [Host Address]> [local filename]

Step 2 Open the file - it should display the key with its hostname and key format - for example:

Step 3 To generate your host server fingerprint you will need to copy the key, decode it and then hash it with either the md5 or sha512 algorithm. You can do this with https://onlinephp.io/ using the code snippet below:

<?php
//$publicKey = [YOUR PUBLIC KEY];
$publicKey = 'ssh-ed25519 YOUR_PUBLIC_KEY_HERE';
$content = explode(' ', $publicKey);
$algo = $content[0] === 'ssh-rsa' ? 'md5' : 'sha512';
echo implode(':', str_split(hash($algo, base64_decode($content[1])), 2));

Here, you should replace the YOUR_PUBLIC_KEY_HERE placeholder in line 3 with your own public key, then execute the code to generate a fingerprint value:

Troubleshooting SFTP connections

If an error is given when you try to save connector instance settings, check that:

• Your credentials are valid

• The associated user has permissions to access the specified root and path directories on the FTP server

It's a good idea to try the same settings in an FTP client - if they work there, they should work when creating a Patchworks instance.

More information

For further information about working with the SFTP connector please see our Configuring SFTP connections page.