Bash Native AWS Federation Script

aws_federate.sh

# Function to URLEncode JSON and Other Strings
urlencode() {
  local LANG=C; local c; while IFS= read -r c; do
    case $c in [a-zA-Z0-9.~_-]) printf "$c"; continue ;; esac
    printf "$c" | od -An -tx1 | tr ' ' % | tr -d '\n'
  done <<EOF
$(fold -w1)
EOF
  echo
}

# I Very frequently use AWS Temporary Credentials to Federate into an AWS Account.
# This will detect the Exported AWS Environment Variables and generate a Federation Signin URL
function aws_federate {
  `which curl &> /dev/null`
  if [ $? -ne 0 ]; then
    echo "Please install curl"
    exit 1
  fi

  `which jq &> /dev/null`
  if [ $? -ne 0 ]; then
    echo "Please install jq"
    exit 1
  fi

  AWS_SESSION_ENC=`echo "{\"sessionId\": \"${AWS_ACCESS_KEY_ID}\", \"sessionKey\": \"${AWS_SECRET_ACCESS_KEY}\", \"sessionToken\": \"${AWS_SESSION_TOKEN}\"}" | urlencode`
  SIGNIN_TOKEN=`curl -ksL "https://signin.aws.amazon.com/federation?Action=getSigninToken&SessionDuration=43200&SessionType=json&Session=${AWS_SESSION_ENC}" | jq -r '.SigninToken'`
  ISSUER=`echo "http://localhost" | urlencode`
  DESTINATION=`echo "https://us-west-2.console.aws.amazon.com/console/home" | urlencode`
  URL="https://signin.aws.amazon.com/federation?Action=login&Issuer=${ISSUER}&Destination=${DESTINATION}&SigninToken=${SIGNIN_TOKEN}"
  echo $URL
}