my ssh-agent zookeeper

ssh-agent-zookeeper.sh

# to use from your .bashrc, do something like:
# if [[ "$-" =~ i ]]; then ~/.ssh-agent-zookeeper.sh; ssh-zoo; fi

function _source_agent_vars {
    if [ -z "$SSH_AGENT_SOCKET_FILE" ]; then
        echo run the ssh-zoo-setup first
        return 1
    fi

    [ -f "$SSH_AGENT_VARS_FILE" ] && source "$SSH_AGENT_VARS_FILE"

    if [ -n "$TMUX" -a -n "$TMUX_NAME" -a "$SSH_AUTH_SOCK" ]; then
        tmux setenv SSH_AGENT_SOCKET_DIR      "$SSH_AGENT_SOCKET_DIR"
        tmux setenv SSH_AGENT_SOCKET_FILE     "$SSH_AGENT_SOCKET_FILE"
        tmux setenv SSH_AGENT_VARS_FILE       "$SSH_AGENT_VARS_FILE"
        tmux setenv SSH_AGENT_IDENTITIES_FILE "$SSH_AGENT_IDENTITIES_FILE"

        tmux setenv SSH_AUTH_SOCK "$SSH_AUTH_SOCK"
        tmux setenv SSH_AGENT_PID "$SSH_AGENT_PID"
    fi
}

function _invoke-ssh-agent {
    if [ -z "$SSH_AGENT_SOCKET_FILE" ]; then
        echo run the ssh-zoo-setup first
        return 1
    fi

    [ -f ~/.zoo.sh ] && rm ~/.zoo.sh

    [ -S "$SSH_AGENT_SOCKET_FILE" ] && (set -x; ssh-agent -a "$SSH_AGENT_SOCKET_FILE" -k)
    [ -e "$SSH_AGENT_SOCKET_FILE" ] && (set -x; rm  "$SSH_AGENT_SOCKET_FILE")

    ssh-agent -a "$SSH_AGENT_SOCKET_FILE" > "$SSH_AGENT_VARS_FILE"
    _source_agent_vars
    if [ -n "$SSH_AGENT_IDENTITIES_FILE" -a -f "$SSH_AGENT_IDENTITIES_FILE" ]; then
        while read line; do
            if [ -f "$line" ]; then
                ssh-add "$line"
            fi
        done < "$SSH_AGENT_IDENTITIES_FILE"
    else
        ssh-add # add default identity
    fi
}
function ssh-zoo-setup {
    # GNOME keyring daemon fucks up ssh-agents badly
    # GNOME_KEYRING_CONTROL=/run/user/1000/keyring-IwU0w9
    # GNOME_KEYRING_PID=13441
    unset GNOME_KEYRING_CONTROL
    unset GNOME_KEYRING_PID

    export SSH_AGENT_SOCKET_DIR=~/.ssh/agent
    export SSH_AGENT_SOCKET_FILE="$SSH_AGENT_SOCKET_DIR/default-agent.socket"
    export SSH_AGENT_VARS_FILE="$SSH_AGENT_SOCKET_DIR/default-agent.sh"
    export SSH_AGENT_IDENTITIES_FILE="$HOME/.ssh-agent-ids"

    [ -d "$SSH_AGENT_SOCKET_DIR" ] || mkdir -p "$SSH_AGENT_SOCKET_DIR"
    chmod 0700 "$SSH_AGENT_SOCKET_DIR"

    if [ -n "$TMUX" ]; then
        TMUX_NAME="$( tmux display -p '#S' )"
        while [[ "$TMUX_NAME" =~ -g$ ]]; do
            TMUX_NAME="${TMUX_NAME%-g}"
        done

        if [[ -n "$TMUX_NAME" && ! "$TMUX_NAME" =~ [^a-zA-Z0-9._-] ]]; then
            export SSH_AGENT_SOCKET_FILE="$SSH_AGENT_SOCKET_DIR/$TMUX_NAME-agent.socket"
            export SSH_AGENT_VARS_FILE="$SSH_AGENT_SOCKET_DIR/$TMUX_NAME-agent.sh"
            export SSH_AGENT_IDENTITIES_FILE="$HOME/.ssh-agent-$TMUX_NAME-ids"
        fi
    fi

    _source_agent_vars
}

function ssh-zoo {
    ssh-zoo-setup
    ssh-add -l &>/dev/null || _invoke-ssh-agent

    echo "Should be all set!"
    echo
    echo "ssh-agent environment:"
    set | grep -E "^(SSH_AGENT_PID|SSH_AUTH_SOCK)" | sed -e 's/^/  /'
    echo
    echo "ssh-agent fingerprints:"
    ssh-add -l | sed -e 's/^/  /'
}