aws-login

aws-login

#!/bin/bash
#
# AWS login to the management console or instance with Session Manager or SSH
#
# Require: aws-vault
#
# Copyright (c) 2022 Jun Futagawa (jfut)
#
# This software is released under the MIT License.
# http://opensource.org/licenses/mit-license.php

set -uo pipefail

# Usage
usage() {
    cat << _EOF_
Usage:
    $(basename ${0}) [-p] [-c] [-s] [-u USERNAME] [TARGET_FILTER]

    Options:
        -p Profile (Default: AWS_PROFILE environment variable)
        -c Console login
        -s Use SSH login
        -u Username for SSH login (Default: ec2-user)

    Examples:
        Login to the management console with AWS_PROFILE environment variable
            $(basename ${0}) -c
        Login to the management console the specified profile
            $(basename ${0}) -c -p profile1
        Login to instance with Session Manager
            $(basename ${0})
        Filter target instances and login with Session Manager
            $(basename ${0}) web
        Filter target instances and login with SSH using admin user
            $(basename ${0}) -s -u admin web
_EOF_
}

console_login() {
    aws-vault login "${AWS_PROFILE}"
}

instance_login() {
    # List
    declare -a TARGET_ARRAY=()
    INSTANCE_LIST=$(aws ec2 describe-instances \
        --query 'Reservations[*].Instances[].[ Tags[?Key==`Name`] | [0].Value, InstanceId, PublicIpAddress, PrivateIpAddress, State.Name ]' \
        --output json \
        | jq -r '.[] | @csv' | sed 's/"//g' | sort | grep "running$" \
        | egrep ${TARGET_FILTER})
    for INSTANCE_INFO in ${INSTANCE_LIST}
    do
        INSTANCE_ID=$(echo ${INSTANCE_INFO} | cut -d',' -f 2)
        TARGET_ARRAY+=(${INSTANCE_ID})
        echo "- $(( ${#TARGET_ARRAY[@]} )): ${INSTANCE_INFO}"
    done

    # Select
    if [[ ${#TARGET_ARRAY[@]} -eq 0 ]]; then
        echo "ERROR: Target running instance not found."
        return
    elif [[ ${#TARGET_ARRAY[@]} -eq 1 ]]; then
        TARGET_INSTANCE=${TARGET_ARRAY[0]}
    else
        echo -n "Select the instance [1..${#TARGET_ARRAY[@]}]: "
        read i
        TARGET_INSTANCE="${TARGET_ARRAY[$(( ${i} - 1 ))]}"
    fi

    # Login
    if [[ "${USE_SSH}" -eq 1 ]]; then
        echo "ssh ${USERNAME}@${TARGET_INSTANCE}"
        ssh "${USERNAME}@${TARGET_INSTANCE}"
    else
        echo "aws ssm start-session --target ${TARGET_INSTANCE}"
        aws ssm start-session --target "${TARGET_INSTANCE}"
    fi
}

# Main
main() {
    AWS_CONSOLE_LOGIN_MODE=0
    AWS_PROFILE="${AWS_PROFILE}"
    USE_SSH=0
    USERNAME="ec2-user"
    while getopts cp:su:h OPT; do
        case "${OPT}" in
            "c" )
                AWS_CONSOLE_LOGIN_MODE=1 ;;
            "p" )
                AWS_PROFILE="${OPTARG}" ;;
            "s" )
                USE_SSH=1 ;;
            "u" )
                USERNAME="${OPTARG}" ;;
            "h" )
                usage
                exit 0
                ;;
            * )
                usage
                exit 1
                ;;
        esac
    done
    shift $((OPTIND - 1))

    TARGET_FILTER=${1:-"^"}

    if [[ "${AWS_CONSOLE_LOGIN_MODE}" -eq 1 ]]; then
        console_login
    else
        instance_login
    fi
}

[[ ${#BASH_SOURCE[@]} = 1 ]] && main "${@}"