Understanding Digital Certificates

Digital certificates serve three crucial purposes: proving your identity, enabling secure communication, and preventing identity theft.

Here’s how the certification process works:

1. Generate your unique cryptographic keys (private and public)
2. Complete an identity verification application
3. Get your application validated by a trusted third party
4. Securely store your credentials together

Using these digital credentials involves:

1. Creating a digital signature with your private key
2. Having others verify your signature using your public key
3. Allowing third parties to authenticate your identity

The Certification Process

Getting a digital certificate involves four main steps:

1. Creating Your Key Pair

• Generate a private key (must remain secret)
• Create its matching public key

2. Applying for Certification

• Compile your identification details
• Create a Certificate Signing Request (CSR)

3. CA Verification

• Submit to a Certificate Authority (CA)
• Receive your verified certificate

4. Setting Up Your Certificate

• Combine your private key with the certificate
• Store everything securely

Technical Implementation

The process begins with creating a P12 file (PKCS#12 format), which serves as a secure container for:

• Your private key
• Your certificate (once issued)
• The certificate chain (once established)

keytool -genkeypair \
    -keysize 4096 \
    -keystore keystore_file.p12 \
    -storetype PKCS12 \
    -alias keystore_file \
    -dname "CN=keystore_file,OU=dataproxy-services" \
    -keyalg RSA \
    -storepass abc

The generated p12 file itself is a type of keystore that can be directly used as a CSR (Certificate Signing Request):

keytool -certreq \
    -keystore keystore_file.p12 \
    -alias keystore_file \
    -file certificate.csr \
    -storepass abc

After the CA verifies and signs your request, you’ll need to merge the original p12 containing the private key to complete the certificate installation:

keytool -importcert \
    -keystore keystore_file.p12 \
    -file certificate.p7b \
    -alias keystore_file \
    -trustcacerts \
    -noprompt \
    -storepass abca

Usage

For practical use, I recommend integrating P12 with Vault for enhanced security. Since P12 files are binary and not transmission-friendly, we first convert them to base64 format:

base64 -i keystore_file.p12 -o p12.base64

Vault includes encrypted storage functionality, and kv is suitable for storing certificate-type data. We store this file in Vault:

vault kv put custom/internal/certificates/kafkaKeyStore [email protected]

Finally, configure your application to use the certificate:

jks:
  secretList:
    - name: kafkaStore
      vaultPath: "custom/internal/certificates/kafkaKeyStore"

This setup allows your application to automatically retrieve the certificate at startup, streamlining the secure authentication process.