Private key password for sftp object?

Hello, Matlab2021 has an sftp object like the old ftp object. That can be used with either password authentication or a public and private key (see help sftp).

Our private key however has a password. The matlab "connection" object can handle this, but there doesn't seem to be a way to pass this to the sftp object and my connection is rejected...

Anyone know how to do this?

(We were previously using the ssh2 toolbox from the fileexchange but this has some problems for us).

Thanks in advance.

Answer 1

[Vidip Jain]

I understand you want to use a private key with a password for SFTP authentication in MATLAB 2021, you can use the following steps to do the same:

1. Create a ‘connection’ object to the SFTP server.
2. Set the ‘PrivateKeyFile’ and ‘PrivateKeyPassword’ properties of the connection object.
3. Create a ‘sftp’ object using the ‘connection’ object.

The ‘connection’ object can be used to manage the SSH connection to the SFTP server. The ‘connection’ object can also be used to specify the private key file and password.

For further information, refer to the documentation links below:

• https://www.mathworks.com/help/matlab/ref/sftp.html

[Garrett Good]

Hello, thank you for your response. I'm returning to this same task this September again. Can you please be more specific on what functionis I use to do this?

I can't give the right inputs to create a connection to the SFTP server using e.g. the "database" class.

[Walter Roberson]

Why not use the syntax

s = sftp(host,user,"PublicKeyFile",publickeyfile,"PrivateKeyFile",privatekeyfile) %uses the key files at the specified locations.

[Garrett Good]

Thank you for your response, Walter.

My ssh understanding is limited but it seems there are more than the 2 possiblities supported by Matlab.

1. username+password
2. public + private key pair.

We do not have a keypair, but rather a private key from a client with a passphrase. We can connect via sftp in a terminal with just the private key and this works. We can also decrypt the key and avoid the password query. Matlab's sftp will only accept a private key as part of a pair and generating a public key from this private one also has not worked (connection is refused).

We used to use this https://www.mathworks.com/matlabcentral/fileexchange/35409-ssh-sftp-scp-for-matlab-v2, which can connect, but now it doesn't like our drivers, and was always quite difficult as compared to a matlab ftp object, in particular, as it's missing a "dir" command.

[Nimit Dhulekar]

Hi Garrett, we introduced

PrivateKeyPassPhrase

in 24b which should satisfy your requirement to pass in a passphrase along with your private key.

https://www.mathworks.com/help/matlab/ref/sftp.html#mw_97c72577-cc4e-4881-aed6-f27c652e5221