Post-Tyranny-Tech-Infrastructure/secrets

Secrets Management with SOPS + Age

This directory contains encrypted secrets for the infrastructure using SOPS with Age encryption.

🔐 Security Model

• Encryption: All secret files encrypted with Age before committing to Git
• Key Storage: Age private key stored OUTSIDE this repository
• Git-Safe: Only encrypted files (.sops.yaml) are committed
• Decryption: Happens at runtime by Ansible or manually with sops

📁 Directory Structure

secrets/
├── README.md              # This file
├── shared.sops.yaml       # Shared secrets (encrypted)
└── clients/
    └── *.sops.yaml        # Per-client secrets (encrypted)

🔑 Age Key Location

IMPORTANT: The Age private key is stored at:

keys/age-key.txt

This file is gitignored and must NEVER be committed.

Key Backup Checklist

✅ You MUST backup the Age key securely:

1. Password Manager: Store in Bitwarden/1Password/etc

   # Copy key content
   cat keys/age-key.txt
   # Store as secure note in password manager
   

2. Print Backup (optional but recommended):

   # Print and store in secure physical location
   cat keys/age-key.txt | lpr
   

3. Encrypted USB Drive (optional):

   # Copy to encrypted USB for offline backup
   cp keys/age-key.txt /Volumes/SecureUSB/infrastructure-age-key.txt
   

⚠️ WARNING: If you lose this key, encrypted secrets are PERMANENTLY UNRECOVERABLE!

🚀 Quick Start

Prerequisites

# Install SOPS and Age
brew install sops age

# Ensure you have the Age key
ls -la keys/age-key.txt

View Encrypted Secrets

# View shared secrets
SOPS_AGE_KEY_FILE=keys/age-key.txt sops secrets/shared.sops.yaml

# View client secrets
SOPS_AGE_KEY_FILE=keys/age-key.txt sops secrets/clients/test.sops.yaml

Edit Encrypted Secrets

# Edit shared secrets (decrypts, opens $EDITOR, re-encrypts on save)
SOPS_AGE_KEY_FILE=keys/age-key.txt sops secrets/shared.sops.yaml

# Edit client secrets
SOPS_AGE_KEY_FILE=keys/age-key.txt sops secrets/clients/test.sops.yaml

Create New Client Secrets

# Copy template
cp secrets/clients/test.sops.yaml secrets/clients/newclient.sops.yaml

# Edit with generated passwords
SOPS_AGE_KEY_FILE=keys/age-key.txt sops secrets/clients/newclient.sops.yaml

Generate Secure Passwords

# Random 32-character password
openssl rand -base64 32

# Random 24-character password
openssl rand -base64 24

# Random hex string (32-byte, 64 characters)
openssl rand -hex 32

🔧 Usage with Ansible

Ansible automatically decrypts SOPS files using the community.sops collection.

In playbooks:

- name: Load client secrets
  community.sops.load_vars:
    file: "{{ playbook_dir }}/../secrets/clients/{{ client_name }}.sops.yaml"
    name: client_secrets

- name: Use decrypted secret
  debug:
    msg: "DB Password: {{ client_secrets.authentik_db_password }}"

Environment variable required:

export SOPS_AGE_KEY_FILE=/path/to/infrastructure/keys/age-key.txt

📝 Secret File Structure

shared.sops.yaml

Contains secrets shared across all infrastructure:

• Hetzner Cloud API token
• Hetzner Storage Box credentials
• ACME email for SSL certificates

clients/*.sops.yaml

Per-client secrets:

• Database passwords (Authentik, Nextcloud)
• Admin passwords
• Secret keys and tokens
• Restic repository password
• OIDC credentials (after generation)

🛠️ Common Tasks

Decrypt to Temporary File

# Decrypt for one-time use
SOPS_AGE_KEY_FILE=keys/age-key.txt sops --decrypt secrets/shared.sops.yaml > /tmp/secrets.yaml

# Use the file
cat /tmp/secrets.yaml

# IMPORTANT: Delete when done
rm /tmp/secrets.yaml

Encrypt New File

# Create plaintext file
cat > secrets/newfile.sops.yaml <<EOF
my_secret: "super-secret-value"
EOF

# Encrypt in place
SOPS_AGE_KEY_FILE=keys/age-key.txt sops --encrypt --in-place secrets/newfile.sops.yaml

Re-encrypt with New Key

If you need to rotate the Age key:

# Generate new key
age-keygen -o keys/age-key-new.txt

# Get public key
grep "public key:" keys/age-key-new.txt

# Update .sops.yaml with new public key

# Re-encrypt all files
for file in secrets/**/*.sops.yaml; do
  SOPS_AGE_KEY_FILE=keys/age-key.txt sops updatekeys -y "$file"
done

# Replace old key
mv keys/age-key.txt keys/age-key-old.txt
mv keys/age-key-new.txt keys/age-key.txt

🔍 Troubleshooting

"Failed to get the data key required to decrypt the SOPS file"

• Cause: Age private key not found or incorrect
• Fix: Ensure SOPS_AGE_KEY_FILE points to correct key

  export SOPS_AGE_KEY_FILE=/full/path/to/keys/age-key.txt
  

"no matching creation rules found"

• Cause: File path doesn't match .sops.yaml regex
• Fix: Ensure filename ends with .sops.yaml

"config file not found"

• Cause: .sops.yaml not in repository root
• Fix: Check .sops.yaml exists at repo root

🔒 Security Best Practices

1. ✅ Never commit keys/age-key.txt
2. ✅ Always encrypt before committing secrets
3. ✅ Backup the key in multiple secure locations
4. ✅ Use strong passwords: minimum 24 characters
5. ✅ Rotate secrets periodically
6. ✅ Limit key access to essential personnel only
7. ✅ Delete temp files after decryption

📚 References

• SOPS Documentation
• Age Documentation
• Ansible SOPS Collection