This script sets up SSH keys for GitHub authentication and configures Git to sign commits and tags with those keys. It cleans up old SSH, GPG, and Git configurations, then generates new keys and updates Git settings.

setup_git.txt

# Part 1: Cleanup
# List the contents of the SSH directory
    ls -l ~/.ssh
# Remove existing SSH keys and configuration
    rm -rf ~/.ssh
# Create a new SSH directory
    mkdir ~/.ssh
# Set permissions for the SSH directory to 700 (read/write/execute for owner)
    chmod 700 ~/.ssh
# List SSH keys currently added to the SSH agent
    ssh-add -l
# Remove all SSH keys from the agent
    ssh-add -D
# Remove the GPG configuration directory
    rm -rf ~/.gnupg
# List global git configuration settings
    git config --global --list
# Remove the existing global git configuration file
    rm -rf ~/.gitconfig
# Create an empty git configuration file
    touch ~/.gitconfig


# Part 2: SSH Key Generation and Setup
# Generate a new SSH key pair with ED25519 algorithm
    ssh-keygen -t ed25519 -C "your_email@example.com"
# Start the SSH agent
    eval "$(ssh-agent -s)"
# Add the generated SSH private key to the agent
    ssh-add ~/.ssh/id_ed25519
# Output the public key to copy for GitHub
    cat ~/.ssh/id_ed25519.pub 	
# Log in to GitHub, go to Settings > SSH and GPG keys, then add the public key.
# Make 2 keys: one for authentication and another for signing, using the same public key for both and give them the same title.
# Edit SSH configuration for GitHub
    echo -e "Host github.com\n    HostName github.com\n    User git\n    IdentityFile ~/.ssh/id_ed25519" > ~/.ssh/config
# Adding GitHub's SSH key to known_hosts...
    ssh-keyscan github.com >> ~/.ssh/known_hosts
# Test SSH connection to GitHub
    ssh -T git@github.com


# Part 3: Git Global Configuration and GPG Signing
# Set global Git user name and email
    git config --global user.name "your_email@example.com"
    git config --global user.email "your_username"
# Enable GPG signing for commits
    git config --global commit.gpgSign true
# Enable GPG signing for tags
    git config --global tag.gpgSign true
# Set GPG format to SSH
    git config --global gpg.format ssh
# Set the SSH public key for signing
    git config --global user.signingkey ~/.ssh/id_ed25519.pub
# Add the signing key to GPG's allowed signers list
    echo "$(git config --get user.email) namespaces=\"git\" $(cat ~/.ssh/id_ed25519.pub)" >> ~/.gnupg/allowed_signers
# Set the allowed signers file for GPG
    git config --global gpg.ssh.allowedSignersFile ~/.gnupg/allowed_signers