Linux Security¶
RSA¶
Create new RSA KEY
GPG¶
Creating a GPG (GNU Privacy Guard) key is a straightforward process that allows you to encrypt, sign, and verify data securely. Below is a step-by-step guide to creating a GPG key on various platforms:
1. Install GPG¶
Before creating a GPG key, ensure that GPG is installed on your system.
On Linux¶
Most Linux distributions come with GPG pre-installed.
- To check if it's installed, run:
If not installed, install it using your package manager:
- For Debian/Ubuntu:
- For Fedora:
On macOS¶
- Use Homebrew to install GPG:
On Windows¶
- Download and install Gpg4win from the official website.
2. Generate a New GPG Key¶
Once GPG is installed, follow these steps to generate a new key:
Step 1: Start the Key Generation Process¶
Run the following command in your terminal or command prompt:
This command allows you to create a new key with detailed options.
Step 2: Choose the Key Type¶
You will be prompted to select the type of key you want to create. The default option is usually sufficient for most users:
Please select what kind of key you want:
(1) RSA and RSA (default)
(2) DSA and Elgamal
(3) DSA (sign only)
(4) RSA (sign only)
Your selection? 1
Press Enter to choose the default (RSA and RSA).
NOTE: I personally use RSA and RSA key type.
Step 3: Specify the Key Size¶
Next, specify the key size. A larger key size provides better security but may take longer to generate:
The default size is 3072 bits, which is recommended. You can press Enter to accept the default or enter 4096 for stronger encryption.
Step 4: Set the Key Expiration¶
Decide how long the key should remain valid. You can set an expiration date or make it never expire:
Please specify how long the key should be valid.
0 = key does not expire
<n> = key expires in n days
<n>w = key expires in n weeks
<n>m = key expires in n months
<n>y = key expires in n years
Key is valid for? (0)
For personal use, you can set it to never expire (0). For organizational use, consider setting an expiration date (e.g., 2y for 2 years).
Step 5: Confirm Your Choices¶
Review the settings and confirm:
Type y and press Enter.
Step 6: Provide User Information¶
You will be asked to provide your name, email address, and an optional comment:
These details will be used to identify your key.
Step 7: Create a Passphrase¶
Set a strong passphrase to protect your private key. This passphrase will be required whenever you use the private key for signing or decrypting data.
Step 8: Wait for Key Generation¶
GPG will generate entropy by performing random calculations. You may need to perform some activities on your computer (e.g., moving the mouse or typing) to speed up the process.
3. Verify Your Key¶
Once the key is generated, you can list all your keys to verify:
This will display your public key along with its fingerprint.
4. Export Your Public Key¶
To share your public key with others, export it using:
This creates a file named public-key.asc containing your public key in ASCII format.
5. Backup Your Private Key¶
It's crucial to back up your private key. Export it securely:
Store the private-key.asc file in a secure location.
6. Upload Your Public Key to a Keyserver (Optional)¶
If you want to make your public key publicly available, upload it to a keyserver:
Replace YOUR_KEY_ID with the ID or fingerprint of your key.