Easily forward ports through an SSH login node.

sshft.sh

sshft() {
    if [ $# -lt 2 ]; then
            echo "usage: sshft host [port|local:remote|local:bridge:remote] ...]"
        return 1
    fi
    if [ -z "$DEFAULT_SSH_PROXY_HOST" ]; then
        echo "No DEFAULT_SSH_PROXY_HOST set."
        return 1
    fi
    FIRST_SSH_ARGS="$DEFAULT_SSH_PROXY_HOST"
    SECOND_SSH_ARGS="$1"
    shift
    while (( "$#" )); do
        if [[ "$1" =~ ^[0-9]+$ ]]; then
            FIRST_SSH_ARGS="$FIRST_SSH_ARGS -L $1:localhost:$1"
            SECOND_SSH_ARGS="$SECOND_SSH_ARGS -L $1:localhost:$1"
        elif [[ "$1" =~ ^[0-9]+:[0-9]+$ ]]; then
            FIRST_PORT=$(echo $1 |cut -d ':' -f 1)
            SECOND_PORT=$(echo $1 |cut -d ':' -f 2)
            FIRST_SSH_ARGS="$FIRST_SSH_ARGS -L $FIRST_PORT:localhost:$FIRST_PORT"
            SECOND_SSH_ARGS="$SECOND_SSH_ARGS -L $FIRST_PORT:localhost:$SECOND_PORT"
        elif [[ "$1" =~ ^[0-9]+:[0-9]+:[0-9]+$ ]]; then
            FIRST_PORT=$(echo $1 |cut -d ':' -f 1)
            SECOND_PORT=$(echo $1 |cut -d ':' -f 2)
            THIRD_PORT=$(echo $1 |cut -d ':' -f 3)
            FIRST_SSH_ARGS="$FIRST_SSH_ARGS -L $FIRST_PORT:localhost:$SECOND_PORT"
            SECOND_SSH_ARGS="$SECOND_SSH_ARGS -L $SECOND_PORT:localhost:$THIRD_PORT"

        else
            echo "usage: sshft host [port|local:remote|local:bridge:remote] ...]"
            return 1
        fi
        shift
    done
    echo ssh $FIRST_SSH_ARGS -t ssh $SECOND_SSH_ARGS
    ssh $FIRST_SSH_ARGS -t ssh $SECOND_SSH_ARGS
}