(Go) How to Parse a X.509 Certificate and Extract its Public Key

Demonstrates how to load an X.509 certificate and extract the public key. Chilkat supports many certificate encodings:

• DER (binary) encoded certificates (.crt/.cer)
• PEM (BASE64) encoded certificates (.pem)
• Load Certificates Directly from Windows Certificate Stores
• PFX/PKCS12 (.pfx/.p12)
• Java KeyStore (.jks)
• Cryptographic Message Syntax Standard - PKCS #7 Certificates (.P7B)

Chilkat Go Downloads Go Package for Windows, MacOS, Linux, Alpine Linux, Solaris

    cert := chilkat.NewCert()

    // Load a DER (binary) encoded certificate.
    // To load from a .pem or .p7b, or any other file format that contains
    // just one certificate, call LoadFromFile in exactly the same way.
    // The LoadFromFile method automatically detects the format and loads the certificate.
    success := cert.LoadFromFile("qa_data/certs/testCert.cer")
    if success == false {
        fmt.Println(cert.LastErrorText())
        cert.DisposeCert()
        return
    }

    // Get the public key:
    pubKey := cert.ExportPublicKey()
    if cert.LastMethodSuccess() != true {
        fmt.Println(cert.LastErrorText())
        cert.DisposeCert()
        return
    }

    // Examine the key type.
    // A PublicKey object can contain an RSA, ECC, or DSA public key.
    // The KeyType property will contain "rsa", "ecc", or "dsa".
    fmt.Println("key type = ", pubKey.KeyType())

    pubKey.DisposePublicKey()

    cert.DisposeCert()