Generate a SSH Key and encrypt it with gpg

generate-ssh.sh

#!/bin/bash

set -eu

DIR='./files/ssh'
OUTPUT_FILE='./files/ssh.tar.gz'

while getopts do: flag
do
    case "${flag}" in
        d) DIR=${OPTARG};;
        o) OUTPUT_FILE=${OPTARG};;
    esac
done

DIR=$(realpath $DIR);
OUTPUT_FILE=$(realpath $OUTPUT_FILE);


CONFIG_CONTENT=$(cat <<EOF
Host *
    HashKnownHosts no
    StrictHostKeyChecking yes
    CheckHostIP no

Host github
    HostName github.com
    User git

Host bitbucket
    Hostname bitbucket.org
    User git

Host gitlab
    Hostname gitlab.com
    User git
EOF
)

echo "@> 🧰 Generating SSH keys in $DIR";

if [ -d $DIR ]; then
  read -p "@> ⚠️ Are you sure you want to delete $DIR? [y/N] " -n 1 -r
  echo
  if [[ ! $REPLY =~ ^[Yy]$ ]]
  then
    exit 1
  fi
  echo "@> 🧹 Cleaning $DIR";
  rm -rf $DIR;
fi

mkdir -p $DIR;

cd $DIR;

ssh-keygen -t ed25519 -C "Espaco Dohler" -f $DIR/ed25519 -N "";

echo "@> 📝 Generating config file";
echo "$CONFIG_CONTENT" > $DIR/config;

# define correct permissions
chmod 600 $DIR/ed25519;
chmod 644 $DIR/ed25519.pub;
chmod 644 $DIR/config;

echo "@> 📦 Generating tarball";

if [ -f "$OUTPUT_FILE.gpg" ]; then
  read -p "@> ⚠️ Are you sure you want to delete $OUTPUT_FILE? [y/N] " -n 1 -r
  echo
  if [[ ! $REPLY =~ ^[Yy]$ ]]
  then
    exit 1
  fi
  echo "@> 🧹 Cleaning $OUTPUT_FILE";
  rm -rf "$OUTPUT_FILE.gpg";
fi

tar -C $DIR -czvf $OUTPUT_FILE *;

echo "@> 🔑 Encrypting tarball";
gpg --symmetric --cipher-algo AES256 --batch --passphrase "$SSH_FILES_PASSPHRASE" $OUTPUT_FILE;

# to decrypt:
# echo "$SSH_FILES_PASSPHRASE" | gpg --batch --passphrase-fd 0 -o files/ssh.tar.gz --decrypt files/ssh.tar.gz.gpg

echo "@> 📝 Public key:";
echo "";
cat $DIR/ed25519.pub;
echo "";

echo "@> 📦 Done!";