JSch how to use with PuTTY private key

Question

I'm trying to use JSch with a private key configuration. I've generated a public and private key using PuTTYgen but am unsure what to do with both of the files.

Which key (public/private) needs transferring to the server?

Answer 1

• First, you need to register your PuTTYgen-generated public key on the server. See Getting ready for public key authentication or (my) Set up SSH public key authentication.

• And finally see Can we use JSch for SSH key-based communication? for details on using the private key in JSch.

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Make sure you use the latest version of JSch, as older versions do not support the .ppk format natively.

Answer 2

Code Snippet for connection using PuTTy private Key (.ppk)

JSch jsch=new JSch();
jsch.setKnownHosts("~\.ssh\know_hosts");
jsch.addIdentity("~\sshkey.ppk");
Session session=jsch.getSession("ec2-user", "54.12.11.90", 22);
session.setConfig("PreferredAuthentications", "publickey");
session.setConfig("StrictHostKeyChecking", "no");
session.connect();
Channel channel=session.openChannel("shell");
channel.setInputStream(System.in);
channel.setOutputStream(System.out);
channel.connect(3*1000);

Have used 0.1.54 version of Jsch

        <dependency>
            <groupId>com.jcraft</groupId>
            <artifactId>jsch</artifactId>
            <version>0.1.54</version>
        </dependency>