SSH port prober (parallel shell execution)

ssh-port-prober.sh

#!/bin/bash

TITLE="SSH Port Prober"
DESCRIPTION="SSH port prober (parallel shell execution)"
VERSION="2.0"
AUTHOR="Jongmin Kim <[email protected]>"
LICENSE="Expat"
EXECUTABLE="$0"

HOST='' # Write a target host here

PORT_START=1
PORT_INCREMENT=2048
PORT_STOP=65535

RUNNER_FILE_PREFIX='runner-'
RUNNER_FILE_SUFFIX='.sh'

OUTPUT_DIR='output'
OUTPUT_COMBINED_FILE='output.log'


ssh_prober_runner_generation() {
    for i in $(seq $PORT_START $PORT_INCREMENT $PORT_STOP); do
        local R_FILE="$RUNNER_FILE_PREFIX$i$RUNNER_FILE_SUFFIX"
        local P_START=$i
        local P_STOP=$(expr $P_START + $PORT_INCREMENT - 1)
        if (( $P_STOP > $PORT_STOP )); then
            P_STOP=$PORT_STOP
        fi
        local O_FILE="$OUTPUT_DIR/output-$P_START.log"

        cat > "$R_FILE" << EOM
#!/bin/bash

for i in \$(seq $P_START $P_STOP)
do
    ssh -T -o ConnectTimeout=2 -p \$i '$HOST' 1>> '$O_FILE' 2>&1
done
EOM
        chmod +x "$R_FILE"
    done
    echo "Runner files created"
}

ssh_prober_runner_execution() {
    for i in $(seq $PORT_START $PORT_INCREMENT $PORT_STOP); do
        local R_FILE="$RUNNER_FILE_PREFIX$i$RUNNER_FILE_SUFFIX"
        mkdir -p "$OUTPUT_DIR"
        echo "Running ./$R_FILE ..."
        "./$R_FILE" &
    done
    echo "Runners executed"
}

ssh_prober_runner_kill() {
    pkill -9 "$RUNNER_FILE_PREFIX"
    if (( $? == 0 )); then
        echo "Runners killed"
    else
        echo "No runners running"
    fi
}

ssh_prober_runner_removal() {
    rm "$RUNNER_FILE_PREFIX"*"$RUNNER_FILE_SUFFIX"
    echo "Runner files removed"
}

ssh_prober_output_combination() {
    for i in $(seq $PORT_START $PORT_INCREMENT $PORT_STOP); do
        local P_START=$i
        local O_FILE="$OUTPUT_DIR/output-$P_START.log"
        local C_FILE="$OUTPUT_COMBINED_FILE"
        cat "$O_FILE" >> "$C_FILE"
    done
    echo "Output files combined"
}

ssh_prober_output_removal() {
    rm -r "$OUTPUT_DIR"
    echo "Output directory removed"
}


if [[ "$1" == "create" ]]; then
    ssh_prober_runner_generation

elif [[ "$1" == "start" ]]; then
    ssh_prober_runner_execution

elif [[ "$1" == "stop" ]]; then
    ssh_prober_runner_kill

elif [[ "$1" == "remove" ]]; then
    ssh_prober_runner_removal

elif [[ "$1" == "combine-output" ]]; then
    ssh_prober_output_combination

elif [[ "$1" == "remove-output" ]]; then
    ssh_prober_output_removal

elif [[ "$1" == "version" ]]; then
    echo "$TITLE"
    echo "  Description:  $DESCRIPTION"
    echo "  Version:      $VERSION"
    echo "  Author:       $AUTHOR"
    echo "  License:      $LICENSE"
    echo "  Executable:   $EXECUTABLE"

elif [[ "$1" == "help" ]]; then
    echo "$TITLE ($VERSION)"
    echo "Usage: $EXECUTABLE (create|start|stop|remove|combine-output|remove-output|version|help)"

else
    echo "$TITLE ($VERSION)"
    echo "Usage: $EXECUTABLE (create|start|stop|remove|combine-output|remove-output|version|help)" 2>&1

fi