Quick setup for ssh, and ssh config file

ssh-key-setup.sh

# set the variables
SSH_HOST="gitlab.com"
SSH_USER=`whoami`
SSH_PORT=22

# create folder with the correct permissions
mkdir -p ~/.ssh/;
chmod 700 ~/.ssh/;

# generate key with u2f/fido
ssh-keygen -t ecdsa-sk -f ~/.ssh/$SSH_USER@$SSH_HOST -b 4096 -P '' -f ~/.ssh/$SSH_USER@$SSH_HOST

# OR without
# ssh-keygen -t rsa -f $SSH_USER@$SSH_HOST -b 4096 -P '';

## cat into config
cat >>   ~/.ssh/config << EOF

Host $SSH_HOST
    HostName $SSH_HOST
    User $SSH_USER
    IdentityFile ~/.ssh/$SSH_USER@$SSH_HOST
    Port $SSH_PORT
EOF

# set the permissions
chmod 600 ~/.ssh/config;

# copy to instance 
ssh-copy-id -p $SSH_PORT -i ~/.ssh/$SSH_USER@$SSH_HOST.pub $SSH_USER@$SSH_HOST

# OR

# ubuntu to clipboard
cat ~/.ssh/$SSH_USER@$SSH_HOST.pub | xclip

# macos to clipboard
cat ~/.ssh/$SSH_USER@$SSH_HOST.pub | pbcopy

######

mkdir -p ~/.ssh 
chmod 700 ~/.ssh
touch ~/.ssh/authorized_keys
chmod 600 ~/.ssh/authorized_keys