Re-use SSH agent in PowerShell

Question

I found an article that shows how you can re-use an SSH agent across multiple command line windows. This is great, however I'm using PowerShell and absolutely suck at it.

Is there a way to get the same functionality from within my PowerShell profile?

Update

Here is a brief overview of the reference post.

Starting ssh-agent sets a bunch of environment variables.

SSH_AGENT_PID=1784
SSH_AUTH_SOCK=/tmp/ssh-QzfPveH696/agent.696

ssh-agent allows you to specify the socket filename. This is what the post suggests to put in your ~/.bashrc (not possible since I'm using PowerShell).

# If no SSH agent is already running, start one now. Re-use sockets so we never
# have to start more than one session.

export SSH_AUTH_SOCK=/home/fboender/.ssh-socket

ssh-add -l >/dev/null 2>&1
if [ $? = 2 ]; then
   # No ssh-agent running
   rm -rf $SSH_AUTH_SOCK
   ssh-agent -a $SSH_AUTH_SOCK >/tmp/.ssh-script
   source /tmp/.ssh-script
   echo $SSH_AGENT_PID > /home/fboender/.ssh-agent-pid
   rm /tmp/.ssh-script
fi

It sets the socket file, runs ssh-add , if not agent is running it cleans some things up and sets one.

So how can I get that into a PowerShell profile?

Answer 1

I know this question is super old now, but I've taken a crack at it anyway.

Assumptions:

1) ssh-agent.exe is the Mingw32 version.

2) ssh-agent.exe is in your powershell path.

        Function Start-SSHAgent{
    param(
        [Parameter(Mandatory=$false,ValueFromPipeline=$true)]
        [string]$socketfile="/p/.ssh-socket",                       # Used as input to ssh-agent, which expects POSIX format paths
        [Parameter(Mandatory=$false)]
        [string]$pidFile="p:\.ssh-agent-pid"                        # Used as input to Out-File which expects Windows format paths
    )
    $env:SSH_AUTH_SOCK=$socketfile
    $agent_is_running = Get-Process | ? { $_.ProcessName -like "ssh-agent*"}
    if($agent_is_running -eq $null){
        $sshAgentOutput = ssh-agent -a $env:SSH_AUTH_SOCK
        $parse = Select-String -InputObject $sshAgentOutput -Pattern "(?m)SSH_AGENT_PID=(\d+)"
        $sshAgentPid = $parse.Matches[0].Groups[1].Value
        $sshAgentPid | Out-File $pidFile
        $env:SSH_AGENT_PID = $sshAgentPid
    }
}

Drop that into your profile.ps1 file, and then you can run Start-SSHAgent (or you can take it out of the function to have it always run as soon as powershell starts.