(Go) Encrypt File using X.509 Certificate using AES in CBC Mode

Demonstrates how to encrypt a file using an X.509 Certificate's public key, where the underlying bulk encryption algorithm is 128-bit AES in CBC mode. (The underlying bulk encryption algorithm can be specified to be other algorithms/strengths.)

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

    // This example requires the Chilkat Crypt API to have been previously unlocked.
    // See Unlock Chilkat Crypt for sample code.

    crypt := chilkat.NewCrypt2()

    // Use public-key cryptography for encryption.
    crypt.SetCryptAlgorithm("pki")

    // Get an X.509 certificate to use for encrypting.
    // Note: Chilkat provides many different ways of loading a certificate, from many different formats,
    // or if on Windows, from the installed certificates on the system.
    // This example simply loads a certificate from a file.
    // Also, for encryption, only the public key is needed.  Digital certificates embed the public key
    // within the X.509 format itself.  Therefore, if you have a certificate, you also have the public key.
    cert := chilkat.NewCert()
    success := cert.LoadFromFile("qa_data/certs/testCert.cer")
    if success != true {
        fmt.Println(cert.LastErrorText())
        crypt.DisposeCrypt2()
        cert.DisposeCert()
        return
    }

    success = crypt.SetEncryptCert(cert)
    if success != true {
        fmt.Println(crypt.LastErrorText())
        crypt.DisposeCrypt2()
        cert.DisposeCert()
        return
    }

    // Indicate the underlying bulk encryption algorithm to be used:
    crypt.SetPkcs7CryptAlg("aes")
    crypt.SetKeyLength(128)

    // Note: When doing public-key encryption the underlying bulk symmetric cipher mode will always be CBC. (at least with Chilkat...)

    // There's one last option that could be set.  If is the RSA encryption encryption/padding scheme. 
    // By default, RSAES_PKCS1-V1_5 is used.  If desired, the OaepPadding property could be set to true to
    // use RSAES_OAEP.  (We'll leave it set at the default value of false)
    crypt.SetOaepPadding(false)

    // Everything is specified.  Now just encrypt...
    // The output is PKCS7 in binary DER format.
    success = crypt.CkEncryptFile("qa_data/hamlet.xml","qa_output/hamlet.p7")
    if success != true {
        fmt.Println(crypt.LastErrorText())
        crypt.DisposeCrypt2()
        cert.DisposeCert()
        return
    }

    fmt.Println("Finished.")

    crypt.DisposeCrypt2()
    cert.DisposeCert()