This is an implementation of the SSH Agent protocol,
used by the canonical ssh-agent program in the OpenSSH distribution
to hold keys and perform signature operations.
I wanted to work on an SSH agent becuase I recently had to SSH into several thousand machines in one operation, and found that the performance bottleneck was in the stock ssh-agent program. The stock agent runs in a single thread and needs to sign each request individually. I hope to use this project to test whether the agent can be made multithreaded and improve performance when performing extremely large bulk SSH operations.
Please don't use this in production. This is an experiment/learning project and not validated as a cryptosystem at all.
SSH controls which agent is in use with the SSH_AUTH_SOCK variable, so
to use an alternate agent set that variable to the auth socket.
By default, this project listens on ./socket in the working directory,
so to use it:
In one terminal;
~/ssh-agent $ sbt run
[info] welcome to sbt 1.6.2 (Homebrew Java 18)
[info] loading global plugins from /Users/user/.sbt/1.0/plugins
[info] loading project definition from /Users/user/ssh-agent/project
[info] loading settings for project root from build.sbt ...
[info] set current project to SshAgent (in build file:/Users/user/ssh-agent)
[info] running com.pygostylia.sshagent.Server
Listening on ./socket
In another terminal in the same directory;
~/ssh-agent $ SSH_AUTH_SOCK=./socket ssh-add
Identity added: /Users/user/.ssh/id_rsa ([email protected])
~/ssh-agent $ SSH_AUTH_SOCK=./socket ssh-add -l
3072 SHA256:xDfojB0NHXp+6H6bRdJbpBB+Sarpp64CL6w9mqUbyxY [email protected] (RSA)
~/ssh-agent $ SSH_AUTH_SOCK=./socket ssh some-other-machine.com
user@some-other-machine ~ $
This project supports only a small set of ssh-agent features, not including agent locking, tokens, constraints, lifetimes, extensions, or removing keys from the agent.
Protocol documentation: SSH Agent Protocol