ssh-init.sh

#!/bin/bash # Prompt for username and emailread -p "Enter the username for the SSH key (e.g., your_username): " USERNAMEread -p "Enter your email address (for key comment): " EMAIL # Define key path based on the usernameif [ "$USERNAME" == "root" ]; then    KEY_PATH="/root/.ssh/id_rsa"else    KEY_PATH="/home/$USERNAME/.ssh/id_rsa"fi # Function to check if a command existscommand_exists() {    command -v "$1" &>/dev/null} # Generate SSH key pair if it doesn't existif [ ! -f "$KEY_PATH" ]; then    echo "Generating new SSH key pair..."        # Create the .ssh directory if it does not exist    if [ "$USERNAME" != "root" ]; then        sudo mkdir -p /home/$USERNAME/.ssh        sudo chown $USERNAME:$USERNAME /home/$USERNAME/.ssh    else        mkdir -p /root/.ssh    fi        ssh-keygen -t rsa -b 4096 -C "$EMAIL" -f "$KEY_PATH" -N ""else    echo "SSH key pair already exists at $KEY_PATH."fi # Display public keyPUBLIC_KEY=$(cat "${KEY_PATH}.pub") # Output the paths to the key filesecho "SSH key pair generated and stored at:"echo "Private key: $KEY_PATH"echo "Public key: ${KEY_PATH}.pub" # Output the public keyecho ""echo "Public key content:"echo "$PUBLIC_KEY"echo "" # Add public key to authorized_keysif [ "$USERNAME" != "root" ]; then    AUTH_KEYS_PATH="/home/$USERNAME/.ssh/authorized_keys"else    AUTH_KEYS_PATH="/root/.ssh/authorized_keys"fi # Create authorized_keys if it does not existif [ ! -f "$AUTH_KEYS_PATH" ]; then    touch "$AUTH_KEYS_PATH"    chmod 600 "$AUTH_KEYS_PATH"    chown $USERNAME:$USERNAME "$AUTH_KEYS_PATH"fi # Append the public key to authorized_keysif ! grep -q "$PUBLIC_KEY" "$AUTH_KEYS_PATH"; then    echo "$PUBLIC_KEY" >> "$AUTH_KEYS_PATH"    echo "Public key added to $AUTH_KEYS_PATH."else    echo "Public key is already present in $AUTH_KEYS_PATH."fi # Provide instructions for copying the key files to the PCecho ""echo "To use these keys on the PC (client machine), you need to transfer the following files:"echo "    $KEY_PATH"echo "    ${KEY_PATH}.pub"echo "Securely transfer these files to your client machine." echo "On the PC, place the private key in the ~/.ssh/ directory and set the correct permissions:"echo "    mkdir -p ~/.ssh"echo "    cp /path/to/id_rsa ~/.ssh/id_rsa"echo "    chmod 600 ~/.ssh/id_rsa"echo ""echo "Make sure to keep your private key secure and never share it." echo "Done." echo "!!! REMEMBER !!!"echo "-> ! check for conflicting files in /etc/ssh/sshd_config.d/"echo "-> ! for PuTTY convert the private key using PuTTYgen to whatever format"echo "-> ! Root login:"echo "PermitRootLogin yes"echo "-> ! recommended (SSH key login):"echo "PubkeyAuthentication yes"echo "PasswordAuthentication no"echo "UsePAM yes"