dotfiles/dotfiles/lib/shellrc/ssh_agent.sh
2014-12-20 03:21:31 -08:00

84 lines
2.2 KiB
Bash

#!/bin/bash
# acquired courtesy of
# http://superuser.com/questions/141044/sharing-the-same-ssh-agent-among-multiple-login-sessions#answer-141241
function sshag_findsockets {
find /tmp -uid $(id -u) -type s -name agent.\* 2>/dev/null
}
function sshag_testsocket {
if [ ! -x "$(which ssh-add)" ] ; then
echo "ssh-add is not available; agent testing aborted" >&2
return 1
fi
if [ X"$1" != X ] ; then
export SSH_AUTH_SOCK=$1
fi
if [ X"$SSH_AUTH_SOCK" = X ] ; then
return 2
fi
if [ -S $SSH_AUTH_SOCK ] ; then
ssh-add -l > /dev/null
if [ $? = 2 ] ; then
echo "Socket $SSH_AUTH_SOCK is dead! Deleting!" >&2
rm -f $SSH_AUTH_SOCK
return 4
else
return 0
fi
else
echo "$SSH_AUTH_SOCK is not a socket!" >&2
return 3
fi
}
function sshag_init {
# ssh agent sockets can be attached to a ssh daemon process or an
# ssh-agent process.
AGENTFOUND=0
# Attempt to find and use the ssh-agent in the current environment
if sshag_testsocket ; then AGENTFOUND=1 ; fi
# If there is no agent in the environment, search /tmp for
# possible agents to reuse before starting a fresh ssh-agent
# process.
if [ $AGENTFOUND = 0 ] ; then
for agentsocket in $(sshag_findsockets) ; do
if [ $AGENTFOUND != 0 ] ; then break ; fi
if sshag_testsocket $agentsocket ; then AGENTFOUND=1 ; fi
done
fi
# If at this point we still haven't located an agent, it's time to
# start a new one
if [ $AGENTFOUND = 0 ] ; then
eval `ssh-agent`
fi
# Clean up
unset AGENTFOUND
unset agentsocket
{ echo "Keys:"; ssh-add -l | sed 's/^/ /'; } >&2
# Display the found socket
echo $SSH_AUTH_SOCK;
}
# If we are not being sourced, but rather running as a subshell,
# let people know how to use the output.
if [[ $0 =~ sshag ]]; then
echo 'Output should be assigned to the environment variable $SSH_AUTH_SOCK.' >&2
sshag_init
# Otherwise, make it convenient to invoke the search.
# When the alias is invoked, it will modify the shell environment.
else
alias sshag="sshag_init"
fi